diff --git a/elasticsearch/qa/messy-test-watcher-with-groovy/src/test/java/org/elasticsearch/messy/tests/ScriptConditionTests.java b/elasticsearch/qa/messy-test-watcher-with-groovy/src/test/java/org/elasticsearch/messy/tests/ScriptConditionTests.java
index 9c3679edc47..39ff34d307d 100644
--- a/elasticsearch/qa/messy-test-watcher-with-groovy/src/test/java/org/elasticsearch/messy/tests/ScriptConditionTests.java
+++ b/elasticsearch/qa/messy-test-watcher-with-groovy/src/test/java/org/elasticsearch/messy/tests/ScriptConditionTests.java
@@ -165,14 +165,15 @@ public class ScriptConditionTests extends ESTestCase {
     public void testScriptConditionThrowException() throws Exception {
         ScriptServiceProxy scriptService = getScriptServiceProxy(tp);
         ExecutableScriptCondition condition = new ExecutableScriptCondition(
-                new ScriptCondition(Script.inline("assert false").build()), logger, scriptService);
+                new ScriptCondition(Script.inline("null.foo").build()), logger, scriptService);
         SearchResponse response = new SearchResponse(InternalSearchResponse.empty(), "", 3, 3, 500L, new ShardSearchFailure[0]);
         WatchExecutionContext ctx = mockExecutionContext("_name", new Payload.XContent(response));
         ScriptCondition.Result result = condition.execute(ctx);
         assertThat(result, notNullValue());
         assertThat(result.status(), is(Condition.Result.Status.FAILURE));
         assertThat(result.reason(), notNullValue());
-        assertThat(result.reason(), containsString("Assertion"));
+        assertThat(result.reason(), containsString("NullPointerException"));
+        assertThat(result.reason(), containsString("Cannot get property 'foo' on null object"));
     }
 
     public void testScriptConditionReturnObject() throws Exception {
diff --git a/elasticsearch/x-pack/graph/src/main/java/org/elasticsearch/xpack/graph/action/TransportGraphExploreAction.java b/elasticsearch/x-pack/graph/src/main/java/org/elasticsearch/xpack/graph/action/TransportGraphExploreAction.java
index ec4d045ce10..0d4cc3db988 100644
--- a/elasticsearch/x-pack/graph/src/main/java/org/elasticsearch/xpack/graph/action/TransportGraphExploreAction.java
+++ b/elasticsearch/x-pack/graph/src/main/java/org/elasticsearch/xpack/graph/action/TransportGraphExploreAction.java
@@ -509,7 +509,7 @@ public class TransportGraphExploreAction extends HandledTransportAction<GraphExp
                 }
 
                 @Override
-                public void onFailure(Throwable e) {
+                public void onFailure(Exception e) {
                     listener.onFailure(e);
             }
             });
@@ -711,13 +711,13 @@ public class TransportGraphExploreAction extends HandledTransportAction<GraphExp
                     }
 
                     @Override
-                    public void onFailure(Throwable e) {
+                    public void onFailure(Exception e) {
                         listener.onFailure(e);
                     }
                 });
-            } catch (Throwable t) {
-                logger.error("unable to execute the graph query", t);
-                listener.onFailure(t);
+            } catch (Exception e) {
+                logger.error("unable to execute the graph query", e);
+                listener.onFailure(e);
             }
         }
 
diff --git a/elasticsearch/x-pack/graph/src/test/java/org/elasticsearch/xpack/graph/test/GraphTests.java b/elasticsearch/x-pack/graph/src/test/java/org/elasticsearch/xpack/graph/test/GraphTests.java
index a4ad8cdb434..5156a1b6eeb 100644
--- a/elasticsearch/x-pack/graph/src/test/java/org/elasticsearch/xpack/graph/test/GraphTests.java
+++ b/elasticsearch/x-pack/graph/src/test/java/org/elasticsearch/xpack/graph/test/GraphTests.java
@@ -270,11 +270,10 @@ public class GraphTests extends ESSingleNodeTestCase {
         try {
             GraphExploreResponse response = grb.get();
             if (response.getShardFailures().length > 0) {
-                throw ((ShardSearchFailure) response.getShardFailures()[0]).getCause();
+                expectedError = response.getShardFailures()[0].getCause();
             }
-        } catch (Throwable rte) {
+        } catch (Exception rte) {
             expectedError = rte;
-
         }
         assertNotNull(expectedError);
         String message = expectedError.toString();
diff --git a/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/action/delete/TransportDeleteLicenseAction.java b/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/action/delete/TransportDeleteLicenseAction.java
index d3b27d58012..f36a6b3f5e4 100644
--- a/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/action/delete/TransportDeleteLicenseAction.java
+++ b/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/action/delete/TransportDeleteLicenseAction.java
@@ -59,7 +59,7 @@ public class TransportDeleteLicenseAction extends TransportMasterNodeAction<Dele
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 listener.onFailure(e);
             }
         });
diff --git a/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/action/put/TransportPutLicenseAction.java b/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/action/put/TransportPutLicenseAction.java
index 2a1063c446a..bbcb0becce8 100644
--- a/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/action/put/TransportPutLicenseAction.java
+++ b/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/action/put/TransportPutLicenseAction.java
@@ -61,7 +61,7 @@ public class TransportPutLicenseAction extends TransportMasterNodeAction<PutLice
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 listener.onFailure(e);
             }
         });
diff --git a/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/core/LicensesService.java b/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/core/LicensesService.java
index d098094644e..52c1e50b2c8 100644
--- a/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/core/LicensesService.java
+++ b/elasticsearch/x-pack/license-plugin/src/main/java/org/elasticsearch/license/plugin/core/LicensesService.java
@@ -427,8 +427,8 @@ public class LicensesService extends AbstractLifecycleComponent implements Clust
             }
 
             @Override
-            public void onFailure(String source, @Nullable Throwable t) {
-                logger.error("unexpected failure during [{}]", t, source);
+            public void onFailure(String source, @Nullable Exception e) {
+                logger.error("unexpected failure during [{}]", e, source);
             }
 
         });
diff --git a/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/AbstractLicensesIntegrationTestCase.java b/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/AbstractLicensesIntegrationTestCase.java
index 76b6f8055dd..c2248c739b5 100644
--- a/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/AbstractLicensesIntegrationTestCase.java
+++ b/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/AbstractLicensesIntegrationTestCase.java
@@ -88,8 +88,8 @@ public abstract class AbstractLicensesIntegrationTestCase extends ESIntegTestCas
             }
 
             @Override
-            public void onFailure(String source, @Nullable Throwable t) {
-                logger.error("error on metaData cleanup after test", t);
+            public void onFailure(String source, @Nullable Exception e) {
+                logger.error("error on metaData cleanup after test", e);
             }
         });
         latch.await();
diff --git a/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/TestUtils.java b/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/TestUtils.java
index a0dd4f5a0da..e8e1e579bef 100644
--- a/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/TestUtils.java
+++ b/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/TestUtils.java
@@ -146,7 +146,7 @@ public class TestUtils {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 latch.countDown();
             }
         });
diff --git a/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/core/LicensesAcknowledgementTests.java b/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/core/LicensesAcknowledgementTests.java
index aa5c9d70486..6bfbb8188ce 100644
--- a/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/core/LicensesAcknowledgementTests.java
+++ b/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/core/LicensesAcknowledgementTests.java
@@ -157,7 +157,7 @@ public class LicensesAcknowledgementTests extends ESSingleNodeTestCase {
         }
 
         @Override
-        public void onFailure(Throwable throwable) {
+        public void onFailure(Exception throwable) {
             latch.countDown();
         }
     }
diff --git a/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/core/LicensesManagerServiceTests.java b/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/core/LicensesManagerServiceTests.java
index 9081d75aba2..cab7a9ce79d 100644
--- a/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/core/LicensesManagerServiceTests.java
+++ b/elasticsearch/x-pack/license-plugin/src/test/java/org/elasticsearch/license/plugin/core/LicensesManagerServiceTests.java
@@ -174,7 +174,7 @@ public class LicensesManagerServiceTests extends ESSingleNodeTestCase {
             }
 
             @Override
-            public void onFailure(Throwable throwable) {
+            public void onFailure(Exception throwable) {
                 latch.countDown();
             }
         });
diff --git a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/action/MonitoringBulkResponse.java b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/action/MonitoringBulkResponse.java
index cd3ca7e9275..b448d19a788 100644
--- a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/action/MonitoringBulkResponse.java
+++ b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/action/MonitoringBulkResponse.java
@@ -84,7 +84,7 @@ public class MonitoringBulkResponse extends ActionResponse {
         }
 
         Error(StreamInput in) throws IOException {
-            this(in.<Throwable>readThrowable());
+            this(in.readException());
         }
 
         @Override
diff --git a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/action/TransportMonitoringBulkAction.java b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/action/TransportMonitoringBulkAction.java
index 6c0a83b8a3e..66acc6d28f6 100644
--- a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/action/TransportMonitoringBulkAction.java
+++ b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/action/TransportMonitoringBulkAction.java
@@ -114,8 +114,8 @@ public class TransportMonitoringBulkAction extends HandledTransportAction<Monito
                 }
 
                 @Override
-                public void onFailure(Throwable t) {
-                    listener.onResponse(new MonitoringBulkResponse(buildTookInMillis(startTimeNanos), new MonitoringBulkResponse.Error(t)));
+                public void onFailure(Exception e) {
+                    listener.onResponse(new MonitoringBulkResponse(buildTookInMillis(startTimeNanos), new MonitoringBulkResponse.Error(e)));
                 }
             });
         }
diff --git a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/AgentService.java b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/AgentService.java
index cb0389684b4..37cfd5617fa 100644
--- a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/AgentService.java
+++ b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/AgentService.java
@@ -204,8 +204,8 @@ public class AgentService extends AbstractLifecycleComponent {
                 } catch (InterruptedException e) {
                     logger.trace("interrupted");
                     Thread.currentThread().interrupt();
-                } catch (Throwable t) {
-                    logger.error("background thread had an uncaught exception", t);
+                } catch (Exception e) {
+                    logger.error("background thread had an uncaught exception", e);
                 }
             }
             logger.debug("worker shutdown");
diff --git a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/exporter/http/HttpExporter.java b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/exporter/http/HttpExporter.java
index 4f4027ba65e..e2bb090d295 100644
--- a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/exporter/http/HttpExporter.java
+++ b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/exporter/http/HttpExporter.java
@@ -59,9 +59,6 @@ import java.util.Map;
 import java.util.stream.Collectors;
 import java.util.stream.StreamSupport;
 
-/**
- *
- */
 public class HttpExporter extends Exporter {
 
     public static final String TYPE = "http";
@@ -664,9 +661,9 @@ public class HttpExporter extends Exporter {
                     }
                 } catch (InterruptedException e) {
                     // ignore, if closed, good....
-                } catch (Throwable t) {
+                } catch (Exception e) {
                     logger.debug("error in keep alive thread, shutting down (will be restarted after a successful connection has been " +
-                            "made) {}", ExceptionsHelper.detailedMessage(t));
+                            "made) {}", ExceptionsHelper.detailedMessage(e));
                     return;
                 }
             }
diff --git a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/exporter/local/LocalExporter.java b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/exporter/local/LocalExporter.java
index 99cd651b42f..efc545c3887 100644
--- a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/exporter/local/LocalExporter.java
+++ b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/agent/exporter/local/LocalExporter.java
@@ -211,8 +211,8 @@ public class LocalExporter extends Exporter implements ClusterStateListener, Cle
             }
 
             @Override
-            public void onFailure(Throwable throwable) {
-                logger.error("failed to update monitoring index template [{}]", throwable, template);
+            public void onFailure(Exception e) {
+                logger.error("failed to update monitoring index template [{}]", e, template);
             }
         });
     }
@@ -296,7 +296,7 @@ public class LocalExporter extends Exporter implements ClusterStateListener, Cle
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 logger.error("failed to delete indices", e);
             }
         });
diff --git a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/cleaner/CleanerService.java b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/cleaner/CleanerService.java
index b414cf966ab..524f494900f 100644
--- a/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/cleaner/CleanerService.java
+++ b/elasticsearch/x-pack/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/cleaner/CleanerService.java
@@ -179,8 +179,8 @@ public class CleanerService extends AbstractLifecycleComponent {
             for (Listener listener : listeners) {
                 try {
                     listener.onCleanUpIndices(retention);
-                } catch (Throwable t) {
-                    logger.error("listener failed to clean indices", t);
+                } catch (Exception e) {
+                    logger.error("listener failed to clean indices", e);
                 }
             }
 
@@ -209,8 +209,8 @@ public class CleanerService extends AbstractLifecycleComponent {
         }
 
         @Override
-        public void onFailure(Throwable t) {
-            logger.error("failed to clean indices", t);
+        public void onFailure(Exception e) {
+            logger.error("failed to clean indices", e);
         }
 
         /**
diff --git a/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/action/MonitoringBulkTests.java b/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/action/MonitoringBulkTests.java
index 3b2046f4eea..46a67d2ab65 100644
--- a/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/action/MonitoringBulkTests.java
+++ b/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/action/MonitoringBulkTests.java
@@ -81,9 +81,9 @@ public class MonitoringBulkTests extends MonitoringIntegTestCase {
 
             threads[i] = new Thread(new AbstractRunnable() {
                 @Override
-                public void onFailure(Throwable t) {
-                    logger.error("unexpected error in exporting thread", t);
-                    exceptions.add(t);
+                public void onFailure(Exception e) {
+                    logger.error("unexpected error in exporting thread", e);
+                    exceptions.add(e);
                 }
 
                 @Override
diff --git a/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/action/TransportMonitoringBulkActionTests.java b/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/action/TransportMonitoringBulkActionTests.java
index c3c8c32b8da..885cb837672 100644
--- a/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/action/TransportMonitoringBulkActionTests.java
+++ b/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/action/TransportMonitoringBulkActionTests.java
@@ -152,8 +152,8 @@ public class TransportMonitoringBulkActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(String source, Throwable t) {
-                fail("unexpected exception: " + t);
+            public void onFailure(String source, Exception e) {
+                fail("unexpected exception: " + e);
             }
         });
 
diff --git a/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/agent/exporter/ExportersTests.java b/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/agent/exporter/ExportersTests.java
index 4751dd7bd83..c9a9563feec 100644
--- a/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/agent/exporter/ExportersTests.java
+++ b/elasticsearch/x-pack/monitoring/src/test/java/org/elasticsearch/xpack/monitoring/agent/exporter/ExportersTests.java
@@ -296,9 +296,9 @@ public class ExportersTests extends ESTestCase {
             logger.debug("--> exporting thread [{}] exports {} documents", threadNum, threadDocs);
             threads[i] = new Thread(new AbstractRunnable() {
                 @Override
-                public void onFailure(Throwable t) {
-                    logger.error("unexpected error in exporting thread", t);
-                    exceptions.add(t);
+                public void onFailure(Exception e) {
+                    logger.error("unexpected error in exporting thread", e);
+                    exceptions.add(e);
                 }
 
                 @Override
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/SecurityLifecycleService.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/SecurityLifecycleService.java
index f174df21d52..f977bee3a51 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/SecurityLifecycleService.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/SecurityLifecycleService.java
@@ -76,7 +76,7 @@ public class SecurityLifecycleService extends AbstractComponent implements Clust
             if (nativeUserStore.canStart(event.state(), master)) {
                 threadPool.generic().execute(new AbstractRunnable() {
                     @Override
-                    public void onFailure(Throwable throwable) {
+                    public void onFailure(Exception throwable) {
                         logger.error("failed to start native user store service", throwable);
                         assert false : "security lifecycle services startup failed";
                     }
@@ -95,7 +95,7 @@ public class SecurityLifecycleService extends AbstractComponent implements Clust
             if (nativeRolesStore.canStart(event.state(), master)) {
                 threadPool.generic().execute(new AbstractRunnable() {
                     @Override
-                    public void onFailure(Throwable throwable) {
+                    public void onFailure(Exception throwable) {
                         logger.error("failed to start native roles store services", throwable);
                         assert false : "security lifecycle services startup failed";
                     }
@@ -117,7 +117,7 @@ public class SecurityLifecycleService extends AbstractComponent implements Clust
                     threadPool.generic().execute(new AbstractRunnable() {
 
                         @Override
-                        public void onFailure(Throwable throwable) {
+                        public void onFailure(Exception throwable) {
                             logger.error("failed to start index audit trail services", throwable);
                             assert false : "security lifecycle services startup failed";
                         }
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/SecurityTemplateService.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/SecurityTemplateService.java
index eef53799cf2..d4d580a4978 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/SecurityTemplateService.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/SecurityTemplateService.java
@@ -90,8 +90,8 @@ public class SecurityTemplateService extends AbstractComponent implements Cluste
                 if (createTemplate && templateCreationPending.compareAndSet(false, true)) {
                     threadPool.generic().execute(new AbstractRunnable() {
                         @Override
-                        public void onFailure(Throwable t) {
-                            logger.warn("failed to create security index template", t);
+                        public void onFailure(Exception e) {
+                            logger.warn("failed to create security index template", e);
                             templateCreationPending.set(false);
                         }
 
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/filter/SecurityActionFilter.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/filter/SecurityActionFilter.java
index bafdacac3e3..6adde44d6dc 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/filter/SecurityActionFilter.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/filter/SecurityActionFilter.java
@@ -44,9 +44,6 @@ import java.util.function.Predicate;
 
 import static org.elasticsearch.xpack.security.support.Exceptions.authorizationError;
 
-/**
- *
- */
 public class SecurityActionFilter extends AbstractComponent implements ActionFilter {
 
     private static final Predicate<String> LICENSE_EXPIRATION_ACTION_MATCHER = HealthAndStatsPrivilege.INSTANCE.predicate();
@@ -109,8 +106,8 @@ public class SecurityActionFilter extends AbstractComponent implements ActionFil
             } else {
                 chain.proceed(task, action, request, listener);
             }
-        } catch (Throwable t) {
-            listener.onFailure(t);
+        } catch (Exception e) {
+            listener.onFailure(e);
         }
     }
 
@@ -231,7 +228,7 @@ public class SecurityActionFilter extends AbstractComponent implements ActionFil
         }
 
         @Override
-        public void onFailure(Throwable e) {
+        public void onFailure(Exception e) {
             if (threadContext != null) {
                 threadContext.restore();
             }
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportDeleteRoleAction.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportDeleteRoleAction.java
index 48b65921541..7b5f50c7aed 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportDeleteRoleAction.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportDeleteRoleAction.java
@@ -44,7 +44,7 @@ public class TransportDeleteRoleAction extends HandledTransportAction<DeleteRole
                 }
 
                 @Override
-                public void onFailure(Throwable t) {
+                public void onFailure(Exception t) {
                     listener.onFailure(t);
                 }
             });
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportGetRolesAction.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportGetRolesAction.java
index bfaa684c04e..a58c6301141 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportGetRolesAction.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportGetRolesAction.java
@@ -77,7 +77,7 @@ public class TransportGetRolesAction extends HandledTransportAction<GetRolesRequ
                 }
 
                 @Override
-                public void onFailure(Throwable t) {
+                public void onFailure(Exception t) {
                     logger.error("failed to retrieve role [{}]", t, rolename);
                     listener.onFailure(t);
                 }
@@ -95,7 +95,7 @@ public class TransportGetRolesAction extends HandledTransportAction<GetRolesRequ
                 }
 
                 @Override
-                public void onFailure(Throwable t) {
+                public void onFailure(Exception t) {
                     logger.error("failed to retrieve role [{}]", t,
                             Strings.arrayToDelimitedString(request.names(), ","));
                     listener.onFailure(t);
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportPutRoleAction.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportPutRoleAction.java
index 2cb1f983135..1a52983b117 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportPutRoleAction.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/role/TransportPutRoleAction.java
@@ -48,7 +48,7 @@ public class TransportPutRoleAction extends HandledTransportAction<PutRoleReques
             }
 
             @Override
-            public void onFailure(Throwable t) {
+            public void onFailure(Exception t) {
                 listener.onFailure(t);
             }
         });
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportChangePasswordAction.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportChangePasswordAction.java
index 0cffe5bab86..17d0356e5a0 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportChangePasswordAction.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportChangePasswordAction.java
@@ -12,7 +12,6 @@ import org.elasticsearch.cluster.metadata.IndexNameExpressionResolver;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.xpack.security.authc.esnative.NativeUsersStore;
-import org.elasticsearch.xpack.security.authc.esnative.ReservedRealm;
 import org.elasticsearch.xpack.security.user.AnonymousUser;
 import org.elasticsearch.xpack.security.user.SystemUser;
 import org.elasticsearch.threadpool.ThreadPool;
@@ -50,7 +49,7 @@ public class TransportChangePasswordAction extends HandledTransportAction<Change
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 listener.onFailure(e);
             }
         });
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportDeleteUserAction.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportDeleteUserAction.java
index 387da62f59f..207bac9ba17 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportDeleteUserAction.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportDeleteUserAction.java
@@ -54,7 +54,7 @@ public class TransportDeleteUserAction extends HandledTransportAction<DeleteUser
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 listener.onFailure(e);
             }
         });
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportGetUsersAction.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportGetUsersAction.java
index 645871ded3e..7a7a5fc962a 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportGetUsersAction.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportGetUsersAction.java
@@ -78,7 +78,7 @@ public class TransportGetUsersAction extends HandledTransportAction<GetUsersRequ
                 }
 
                 @Override
-                public void onFailure(Throwable e) {
+                public void onFailure(Exception e) {
                     logger.error("failed to retrieve user [{}]", e, username);
                     listener.onFailure(e);
                 }
@@ -94,7 +94,7 @@ public class TransportGetUsersAction extends HandledTransportAction<GetUsersRequ
                 }
 
                 @Override
-                public void onFailure(Throwable e) {
+                public void onFailure(Exception e) {
                     logger.error("failed to retrieve user [{}]", e,
                             Strings.arrayToDelimitedString(request.usernames(), ","));
                     listener.onFailure(e);
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportPutUserAction.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportPutUserAction.java
index b4352ce454a..a8de5a48113 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportPutUserAction.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/action/user/TransportPutUserAction.java
@@ -59,7 +59,7 @@ public class TransportPutUserAction extends HandledTransportAction<PutUserReques
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 logger.error("failed to put user [{}]", e, request.username());
                 listener.onFailure(e);
             }
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/audit/index/IndexAuditTrail.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/audit/index/IndexAuditTrail.java
index bc1f00f0d70..e3b00743df7 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/audit/index/IndexAuditTrail.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/audit/index/IndexAuditTrail.java
@@ -886,7 +886,7 @@ public class IndexAuditTrail extends AbstractComponent implements AuditTrail, Cl
                     INDEX_TEMPLATE_NAME);
             threadPool.generic().execute(new AbstractRunnable() {
                 @Override
-                public void onFailure(Throwable throwable) {
+                public void onFailure(Exception throwable) {
                     logger.error("failed to update security audit index template [{}]", throwable, INDEX_TEMPLATE_NAME);
                 }
 
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/esnative/NativeUsersStore.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/esnative/NativeUsersStore.java
index 37bc6a135ad..c4b5c53a6f5 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/esnative/NativeUsersStore.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/esnative/NativeUsersStore.java
@@ -159,7 +159,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
             }
 
             @Override
-            public void onFailure(Throwable t) {
+            public void onFailure(Exception t) {
                 if (t instanceof IndexNotFoundException) {
                     logger.trace("failed to retrieve user [{}] since security index does not exist", username);
                     // We don't invoke the onFailure listener here, instead
@@ -228,7 +228,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
                 }
 
                 @Override
-                public void onFailure(Throwable t) {
+                public void onFailure(Exception t) {
                     // attempt to clear scroll response
                     if (lastResponse != null && lastResponse.getScrollId() != null) {
                         clearScrollResponse(lastResponse.getScrollId());
@@ -260,7 +260,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
             }
 
             @Override
-            public void onFailure(Throwable t) {
+            public void onFailure(Exception t) {
                 if (t instanceof IndexNotFoundException) {
                     logger.trace("failed to retrieve user [{}] since security index does not exist", t, username);
                 } else {
@@ -287,7 +287,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
                 }
 
                 @Override
-                public void onFailure(Throwable t) {
+                public void onFailure(Exception t) {
                     if (t instanceof IndexNotFoundException) {
                         logger.trace("could not retrieve user [{}] because security index does not exist", t, user);
                     } else {
@@ -334,7 +334,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
                     }
 
                     @Override
-                    public void onFailure(Throwable e) {
+                    public void onFailure(Exception e) {
                         Throwable cause = e;
                         if (e instanceof ElasticsearchException) {
                             cause = ExceptionsHelper.unwrapCause(e);
@@ -368,7 +368,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
                     }
 
                     @Override
-                    public void onFailure(Throwable e) {
+                    public void onFailure(Exception e) {
                         listener.onFailure(e);
                     }
                 });
@@ -410,7 +410,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
                     }
 
                     @Override
-                    public void onFailure(Throwable e) {
+                    public void onFailure(Exception e) {
                         Throwable cause = e;
                         if (e instanceof ElasticsearchException) {
                             cause = ExceptionsHelper.unwrapCause(e);
@@ -455,7 +455,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
                     }
 
                     @Override
-                    public void onFailure(Throwable e) {
+                    public void onFailure(Exception e) {
                         listener.onFailure(e);
                     }
                 });
@@ -479,7 +479,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
                 }
 
                 @Override
-                public void onFailure(Throwable e) {
+                public void onFailure(Exception e) {
                     listener.onFailure(e);
                 }
             });
@@ -550,9 +550,9 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
         if (state.compareAndSet(State.STARTED, State.STOPPING)) {
             try {
                 userPoller.stop();
-            } catch (Throwable t) {
+            } catch (Exception e) {
                 state.set(State.FAILED);
-                throw t;
+                throw e;
             } finally {
                 state.set(State.STOPPED);
             }
@@ -594,10 +594,10 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
         return securityIndexExists;
     }
 
-    char[] reservedUserPassword(String username) throws Throwable {
+    char[] reservedUserPassword(String username) throws Exception {
         assert started();
         final AtomicReference<char[]> passwordHash = new AtomicReference<>();
-        final AtomicReference<Throwable> failure = new AtomicReference<>();
+        final AtomicReference<Exception> failure = new AtomicReference<>();
         final CountDownLatch latch = new CountDownLatch(1);
         client.prepareGet(SecurityTemplateService.SECURITY_INDEX_NAME, RESERVED_USER_DOC_TYPE, username)
                 .execute(new LatchedActionListener<>(new ActionListener<GetResponse>() {
@@ -615,7 +615,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
                     }
 
                     @Override
-                    public void onFailure(Throwable e) {
+                    public void onFailure(Exception e) {
                         if (e instanceof IndexNotFoundException) {
                             logger.trace("could not retrieve built in user [{}] password since security index does not exist", e, username);
                         } else {
@@ -634,7 +634,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
             failure.set(e);
         }
 
-        Throwable failureCause = failure.get();
+        Exception failureCause = failure.get();
         if (failureCause != null) {
             // if there is any sort of failure we need to throw an exception to prevent the fallback to the default password...
             throw failureCause;
@@ -651,7 +651,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
             }
 
             @Override
-            public void onFailure(Throwable t) {
+            public void onFailure(Exception t) {
                 // Not really much to do here except for warn about it...
                 logger.warn("failed to clear scroll [{}]", t, scrollId);
             }
@@ -669,7 +669,7 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 logger.error("unable to clear realm cache for user [{}]", e, username);
                 ElasticsearchException exception = new ElasticsearchException("clearing the cache for [" + username
                         + "] failed. please clear the realm cache manually", e);
@@ -838,21 +838,22 @@ public class NativeUsersStore extends AbstractComponent implements ClusterStateL
             }
 
             // call listeners
-            Throwable th = null;
+            RuntimeException ex = null;
             for (ChangeListener listener : listeners) {
                 try {
                     listener.onUsersChanged(changedUsers);
-                } catch (Throwable t) {
-                    th = ExceptionsHelper.useOrSuppress(th, t);
+                } catch (Exception e) {
+                    if (ex == null) ex = new RuntimeException("exception while notifying listeners");
+                    ex.addSuppressed(e);
                 }
             }
 
-            ExceptionsHelper.reThrowIfNotNull(th);
+            if (ex != null) throw ex;
         }
 
         @Override
-        public void onFailure(Throwable t) {
-            logger.error("error occurred while checking the native users for changes", t);
+        public void onFailure(Exception e) {
+            logger.error("error occurred while checking the native users for changes", e);
         }
 
         private boolean isStopped() {
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/esnative/ReservedRealm.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/esnative/ReservedRealm.java
index 2c2d0a09a29..52aa20550af 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/esnative/ReservedRealm.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/esnative/ReservedRealm.java
@@ -131,7 +131,7 @@ public class ReservedRealm extends CachingUsernamePasswordRealm {
                 return DEFAULT_PASSWORD_HASH;
             }
             return passwordHash;
-        } catch (Throwable e) {
+        } catch (Exception e) {
             logger.error("failed to retrieve password hash for reserved user [{}]", e, username);
             return null;
         }
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/file/FileUserPasswdStore.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/file/FileUserPasswdStore.java
index ebd14bae17b..8190ac0e692 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/file/FileUserPasswdStore.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/file/FileUserPasswdStore.java
@@ -37,9 +37,6 @@ import static java.util.Collections.emptyMap;
 import static java.util.Collections.unmodifiableMap;
 import static org.elasticsearch.xpack.security.support.SecurityFiles.openAtomicMoveWriter;
 
-/**
- *
- */
 public class FileUserPasswdStore {
 
     private final ESLogger logger;
@@ -111,8 +108,8 @@ public class FileUserPasswdStore {
     static Map<String, char[]> parseFileLenient(Path path, ESLogger logger) {
         try {
             return parseFile(path, logger);
-        } catch (Throwable t) {
-            logger.error("failed to parse users file [{}]. skipping/removing all users...", t, path.toAbsolutePath());
+        } catch (Exception e) {
+            logger.error("failed to parse users file [{}]. skipping/removing all users...", e, path.toAbsolutePath());
             return emptyMap();
         }
     }
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/file/FileUserRolesStore.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/file/FileUserRolesStore.java
index b5bee42e46b..aa03091112b 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/file/FileUserRolesStore.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/file/FileUserRolesStore.java
@@ -37,9 +37,6 @@ import static java.util.Collections.emptyMap;
 import static java.util.Collections.unmodifiableMap;
 import static org.elasticsearch.xpack.security.support.SecurityFiles.openAtomicMoveWriter;
 
-/**
- *
- */
 public class FileUserRolesStore {
 
     private static final Pattern USERS_DELIM = Pattern.compile("\\s*,\\s*");
@@ -103,8 +100,8 @@ public class FileUserRolesStore {
     static Map<String, String[]> parseFileLenient(Path path, ESLogger logger) {
         try {
             return parseFile(path, logger);
-        } catch (Throwable t) {
-            logger.error("failed to parse users_roles file [{}]. skipping/removing all entries...", t, path.toAbsolutePath());
+        } catch (Exception e) {
+            logger.error("failed to parse users_roles file [{}]. skipping/removing all entries...", e, path.toAbsolutePath());
             return emptyMap();
         }
     }
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/support/DnRoleMapper.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/support/DnRoleMapper.java
index bfa74b9f190..2eefccdc2db 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/support/DnRoleMapper.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authc/support/DnRoleMapper.java
@@ -95,8 +95,8 @@ public class DnRoleMapper {
     public static Map<DN, Set<String>> parseFileLenient(Path path, ESLogger logger, String realmType, String realmName) {
         try {
             return parseFile(path, logger, realmType, realmName);
-        } catch (Throwable t) {
-            logger.error("failed to parse role mappings file [{}]. skipping/removing all mappings...", t, path.toAbsolutePath());
+        } catch (Exception e) {
+            logger.error("failed to parse role mappings file [{}]. skipping/removing all mappings...", e, path.toAbsolutePath());
             return emptyMap();
         }
     }
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authz/store/FileRolesStore.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authz/store/FileRolesStore.java
index 57f8a16eee7..31be9d091ae 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authz/store/FileRolesStore.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authz/store/FileRolesStore.java
@@ -46,9 +46,6 @@ import static java.util.Collections.emptySet;
 import static java.util.Collections.unmodifiableMap;
 import static org.elasticsearch.xpack.security.Security.setting;
 
-/**
- *
- */
 public class FileRolesStore extends AbstractLifecycleComponent implements RolesStore {
 
     public static final Setting<String> ROLES_FILE_SETTING =
@@ -288,8 +285,8 @@ public class FileRolesStore extends AbstractLifecycleComponent implements RolesS
                 try {
                     permissions = parseFile(file, logger, settings);
                     logger.info("updated roles (roles file [{}] changed)", file.toAbsolutePath());
-                } catch (Throwable t) {
-                    logger.error("could not reload roles file [{}]. Current roles remain unmodified", t, file.toAbsolutePath());
+                } catch (Exception e) {
+                    logger.error("could not reload roles file [{}]. Current roles remain unmodified", e, file.toAbsolutePath());
                     return;
                 }
                 listener.onRefresh();
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authz/store/NativeRolesStore.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authz/store/NativeRolesStore.java
index 63786df2aeb..ad8785ebdbe 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authz/store/NativeRolesStore.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/authz/store/NativeRolesStore.java
@@ -231,7 +231,7 @@ public class NativeRolesStore extends AbstractComponent implements RolesStore, C
                 }
 
                 @Override
-                public void onFailure(Throwable t) {
+                public void onFailure(Exception t) {
                     // attempt to clear the scroll request
                     if (lastResponse != null && lastResponse.getScrollId() != null) {
                         clearScollRequest(lastResponse.getScrollId());
@@ -277,7 +277,7 @@ public class NativeRolesStore extends AbstractComponent implements RolesStore, C
                 }
 
                 @Override
-                public void onFailure(Throwable e) {
+                public void onFailure(Exception e) {
                     logger.error("failed to delete role from the index", e);
                     listener.onFailure(e);
                 }
@@ -311,7 +311,7 @@ public class NativeRolesStore extends AbstractComponent implements RolesStore, C
                         }
 
                         @Override
-                        public void onFailure(Throwable e) {
+                        public void onFailure(Exception e) {
                             logger.error("failed to put role [{}]", e, request.name());
                             listener.onFailure(e);
                         }
@@ -345,7 +345,7 @@ public class NativeRolesStore extends AbstractComponent implements RolesStore, C
                         }
 
                         @Override
-                        public void onFailure(Throwable t) {
+                        public void onFailure(Exception t) {
                             if (t instanceof IndexNotFoundException) {
                                 logger.trace("failed to retrieve role [{}] since security index does not exist", t, roleId);
                             } else {
@@ -403,7 +403,7 @@ public class NativeRolesStore extends AbstractComponent implements RolesStore, C
             }
 
             @Override
-            public void onFailure(Throwable t) {
+            public void onFailure(Exception t) {
                 // Not really much to do here except for warn about it...
                 logger.warn("failed to clear scroll [{}] after retrieving roles", t, scrollId);
             }
@@ -441,7 +441,7 @@ public class NativeRolesStore extends AbstractComponent implements RolesStore, C
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 logger.error("unable to clear cache for role [{}]", e, role);
                 ElasticsearchException exception = new ElasticsearchException("clearing the cache for [" + role
                         + "] failed. please clear the role cache manually", e);
@@ -568,8 +568,8 @@ public class NativeRolesStore extends AbstractComponent implements RolesStore, C
         }
 
         @Override
-        public void onFailure(Throwable t) {
-            logger.error("error occurred while checking the native roles for changes", t);
+        public void onFailure(Exception e) {
+            logger.error("error occurred while checking the native roles for changes", e);
         }
 
         private boolean isStopped() {
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/crypto/InternalCryptoService.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/crypto/InternalCryptoService.java
index 63b6fe75aca..08155f3b34e 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/crypto/InternalCryptoService.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/crypto/InternalCryptoService.java
@@ -12,13 +12,12 @@ import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.common.settings.Setting.Property;
 import org.elasticsearch.common.settings.Settings;
-import org.elasticsearch.common.settings.SettingsModule;
 import org.elasticsearch.env.Environment;
-import org.elasticsearch.xpack.security.authc.support.CharArrays;
 import org.elasticsearch.watcher.FileChangesListener;
 import org.elasticsearch.watcher.FileWatcher;
 import org.elasticsearch.watcher.ResourceWatcherService;
 import org.elasticsearch.xpack.XPackPlugin;
+import org.elasticsearch.xpack.security.authc.support.CharArrays;
 
 import javax.crypto.BadPaddingException;
 import javax.crypto.Cipher;
@@ -28,6 +27,7 @@ import javax.crypto.Mac;
 import javax.crypto.SecretKey;
 import javax.crypto.spec.IvParameterSpec;
 import javax.crypto.spec.SecretKeySpec;
+
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
@@ -45,12 +45,9 @@ import java.util.Objects;
 import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.regex.Pattern;
 
-import static org.elasticsearch.xpack.security.authc.support.SecuredString.constantTimeEquals;
 import static org.elasticsearch.xpack.security.Security.setting;
+import static org.elasticsearch.xpack.security.authc.support.SecuredString.constantTimeEquals;
 
-/**
- *
- */
 public class InternalCryptoService extends AbstractLifecycleComponent implements CryptoService {
 
     public static final String KEY_ALGO = "HmacSHA512";
@@ -232,8 +229,8 @@ public class InternalCryptoService extends AbstractLifecycleComponent implements
             base64RandomKey = pieces[2];
             receivedSignature = pieces[3].substring(0, length);
             text = pieces[3].substring(length);
-        } catch (Throwable t) {
-            logger.error("error occurred while parsing signed text", t);
+        } catch (Exception e) {
+            logger.error("error occurred while parsing signed text", e);
             throw new IllegalArgumentException("tampered signed text");
         }
 
@@ -270,8 +267,8 @@ public class InternalCryptoService extends AbstractLifecycleComponent implements
             if (constantTimeEquals(sig, receivedSignature)) {
                 return text;
             }
-        } catch (Throwable t) {
-            logger.error("error occurred while verifying signed text", t);
+        } catch (Exception e) {
+            logger.error("error occurred while verifying signed text", e);
             throw new IllegalStateException("error while verifying the signed text");
         }
 
@@ -543,29 +540,20 @@ public class InternalCryptoService extends AbstractLifecycleComponent implements
         }
 
         private void callListeners(SecretKey oldSystemKey, SecretKey oldEncryptionKey) {
-            Throwable th = null;
+            RuntimeException ex = null;
             for (Listener listener : listeners) {
                 try {
                     listener.onKeyChange(oldSystemKey, oldEncryptionKey);
-                } catch (Throwable t) {
-                    if (th == null) {
-                        th = t;
-                    } else {
-                        th.addSuppressed(t);
-                    }
+                } catch (Exception e) {
+                    if (ex == null) ex = new RuntimeException("exception calling key change listeners");
+                    ex.addSuppressed(e);
                 }
             }
 
             // all listeners were notified now rethrow
-            if (th != null) {
-                logger.error("called all key change listeners but one or more exceptions was thrown", th);
-                if (th instanceof RuntimeException) {
-                    throw (RuntimeException) th;
-                } else if (th instanceof Error) {
-                    throw (Error) th;
-                } else {
-                    throw new RuntimeException(th);
-                }
+            if (ex != null) {
+                logger.error("called all key change listeners but one or more exceptions was thrown", ex);
+                throw ex;
             }
         }
     }
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/ssl/AbstractSSLService.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/ssl/AbstractSSLService.java
index 63e69307107..8b1a276da95 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/ssl/AbstractSSLService.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/ssl/AbstractSSLService.java
@@ -123,8 +123,8 @@ public abstract class AbstractSSLService extends AbstractComponent {
             sslEngine.setEnabledCipherSuites(supportedCiphers(sslEngine.getSupportedCipherSuites(), ciphers, false));
         } catch (ElasticsearchException e) {
             throw e;
-        } catch (Throwable t) {
-            throw new IllegalArgumentException("failed loading cipher suites [" + Arrays.asList(ciphers) + "]", t);
+        } catch (Exception e) {
+            throw new IllegalArgumentException("failed loading cipher suites [" + Arrays.asList(ciphers) + "]", e);
         }
 
         try {
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/support/SelfReschedulingRunnable.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/support/SelfReschedulingRunnable.java
index c74e875cfa9..d30a0897deb 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/support/SelfReschedulingRunnable.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/support/SelfReschedulingRunnable.java
@@ -49,8 +49,8 @@ public class SelfReschedulingRunnable extends AbstractRunnable {
     }
 
     @Override
-    public void onFailure(Throwable t) {
-        logger.warn("failed to run scheduled task", t);
+    public void onFailure(Exception e) {
+        logger.warn("failed to run scheduled task", e);
     }
 
     @Override
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/SecurityClientTransportService.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/SecurityClientTransportService.java
index b6de8448652..350e1292afc 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/SecurityClientTransportService.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/SecurityClientTransportService.java
@@ -34,8 +34,8 @@ public class SecurityClientTransportService extends TransportService {
         try {
             clientFilter.outbound(action, request);
             super.sendRequest(node, action, request, options, handler);
-        } catch (Throwable t) {
-            handler.handleException(new TransportException("failed sending request", t));
+        } catch (Exception e) {
+            handler.handleException(new TransportException("failed sending request", e));
         }
     }
 
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/SecurityServerTransportService.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/SecurityServerTransportService.java
index 589a762eb82..e6026d37464 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/SecurityServerTransportService.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/SecurityServerTransportService.java
@@ -38,9 +38,6 @@ import static org.elasticsearch.xpack.security.transport.netty.SecurityNettyTran
 import static org.elasticsearch.xpack.security.transport.netty.SecurityNettyTransport.PROFILE_CLIENT_AUTH_SETTING;
 import static org.elasticsearch.xpack.security.transport.netty.SecurityNettyTransport.SSL_SETTING;
 
-/**
- *
- */
 public class SecurityServerTransportService extends TransportService {
 
     public static final String SETTING_NAME = "xpack.security.type";
@@ -81,16 +78,16 @@ public class SecurityServerTransportService extends TransportService {
                 try {
                     clientFilter.outbound(action, request);
                     super.sendRequest(node, action, request, options, new ContextRestoreResponseHandler<>(original, handler));
-                } catch (Throwable t) {
-                    handler.handleException(new TransportException("failed sending request", t));
+                } catch (Exception e) {
+                    handler.handleException(new TransportException("failed sending request", e));
                 }
             }
         } else {
             try {
                 clientFilter.outbound(action, request);
                 super.sendRequest(node, action, request, options, handler);
-            } catch (Throwable t) {
-                handler.handleException(new TransportException("failed sending request", t));
+            } catch (Exception e) {
+                handler.handleException(new TransportException("failed sending request", e));
             }
         }
     }
@@ -194,8 +191,8 @@ public class SecurityServerTransportService extends TransportService {
                 RequestContext context = new RequestContext(request, threadContext);
                 RequestContext.setCurrent(context);
                 handler.messageReceived(request, channel, task);
-            } catch (Throwable t) {
-                channel.sendResponse(t);
+            } catch (Exception e) {
+                channel.sendResponse(e);
             } finally {
                 RequestContext.removeCurrent();
             }
diff --git a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/netty/SecurityNettyTransport.java b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/netty/SecurityNettyTransport.java
index ae7f224f025..9a4adc8e320 100644
--- a/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/netty/SecurityNettyTransport.java
+++ b/elasticsearch/x-pack/security/src/main/java/org/elasticsearch/xpack/security/transport/netty/SecurityNettyTransport.java
@@ -26,14 +26,12 @@ import org.jboss.netty.channel.ChannelHandlerContext;
 import org.jboss.netty.channel.ChannelPipeline;
 import org.jboss.netty.channel.ChannelPipelineFactory;
 import org.jboss.netty.channel.ChannelStateEvent;
-import org.jboss.netty.channel.ExceptionEvent;
 import org.jboss.netty.channel.SimpleChannelHandler;
 import org.jboss.netty.handler.ssl.SslHandler;
 
 import javax.net.ssl.SSLEngine;
 import javax.net.ssl.SSLParameters;
 import java.net.InetSocketAddress;
-import java.util.Collections;
 import java.util.List;
 
 import static org.elasticsearch.xpack.security.Security.featureEnabledSetting;
@@ -113,7 +111,7 @@ public class SecurityNettyTransport extends NettyTransport {
     }
 
     @Override
-    protected void onException(Channel channel, Throwable e) {
+    protected void onException(Channel channel, Exception e) {
         if (isNotSslRecordException(e)) {
             if (logger.isTraceEnabled()) {
                 logger.trace("received plaintext traffic on a encrypted channel, closing connection {}", e, channel);
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/integration/ClearRealmsCacheTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/integration/ClearRealmsCacheTests.java
index a5e9d01bc35..7bb5fa93f25 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/integration/ClearRealmsCacheTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/integration/ClearRealmsCacheTests.java
@@ -146,7 +146,7 @@ public class ClearRealmsCacheTests extends SecurityIntegTestCase {
                 }
 
                 @Override
-                public void onFailure(Throwable e) {
+                public void onFailure(Exception e) {
                     error.set(e);
                     latch.countDown();
                 }
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportDeleteRoleActionTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportDeleteRoleActionTests.java
index e0afd716a0a..e9560e6cfd4 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportDeleteRoleActionTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportDeleteRoleActionTests.java
@@ -55,7 +55,7 @@ public class TransportDeleteRoleActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -96,7 +96,7 @@ public class TransportDeleteRoleActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -108,7 +108,7 @@ public class TransportDeleteRoleActionTests extends ESTestCase {
     }
 
     public void testException() {
-        final Throwable t = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException());
+        final Exception e = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException());
         final String roleName = randomFrom("admin", "dept_a", "restricted");
         NativeRolesStore rolesStore = mock(NativeRolesStore.class);
         TransportDeleteRoleAction action = new TransportDeleteRoleAction(Settings.EMPTY, mock(ThreadPool.class), mock(ActionFilters.class),
@@ -124,7 +124,7 @@ public class TransportDeleteRoleActionTests extends ESTestCase {
                 Object[] args = invocation.getArguments();
                 assert args.length == 2;
                 ActionListener<Boolean> listener = (ActionListener<Boolean>) args[1];
-                listener.onFailure(t);
+                listener.onFailure(e);
                 return null;
             }
         }).when(rolesStore).deleteRole(eq(request), any(ActionListener.class));
@@ -138,14 +138,14 @@ public class TransportDeleteRoleActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
 
         assertThat(responseRef.get(), is(nullValue()));
         assertThat(throwableRef.get(), is(notNullValue()));
-        assertThat(throwableRef.get(), is(sameInstance(t)));
+        assertThat(throwableRef.get(), is(sameInstance(e)));
         verify(rolesStore, times(1)).deleteRole(eq(request), any(ActionListener.class));
     }
 }
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportGetRolesActionTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportGetRolesActionTests.java
index 825f2540af5..2205f0cbcf7 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportGetRolesActionTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportGetRolesActionTests.java
@@ -89,7 +89,7 @@ public class TransportGetRolesActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -158,7 +158,7 @@ public class TransportGetRolesActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -251,7 +251,7 @@ public class TransportGetRolesActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -273,7 +273,7 @@ public class TransportGetRolesActionTests extends ESTestCase {
     }
 
     public void testException() {
-        final Throwable t = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException());
+        final Exception e = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException());
         final List<RoleDescriptor> storeRoleDescriptors = randomRoleDescriptors();
         NativeRolesStore rolesStore = mock(NativeRolesStore.class);
         SecurityContext context = mock(SecurityContext.class);
@@ -290,7 +290,7 @@ public class TransportGetRolesActionTests extends ESTestCase {
                     Object[] args = invocation.getArguments();
                     assert args.length == 2;
                     ActionListener<RoleDescriptor> listener = (ActionListener<RoleDescriptor>) args[1];
-                    listener.onFailure(t);
+                    listener.onFailure(e);
                     return null;
                 }
             }).when(rolesStore).getRoleDescriptor(eq(request.names()[0]), any(ActionListener.class));
@@ -301,7 +301,7 @@ public class TransportGetRolesActionTests extends ESTestCase {
                     Object[] args = invocation.getArguments();
                     assert args.length == 2;
                     ActionListener<List<RoleDescriptor>> listener = (ActionListener<List<RoleDescriptor>>) args[1];
-                    listener.onFailure(t);
+                    listener.onFailure(e);
                     return null;
                 }
             }).when(rolesStore).getRoleDescriptors(aryEq(request.names()), any(ActionListener.class));
@@ -316,13 +316,13 @@ public class TransportGetRolesActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
 
         assertThat(throwableRef.get(), is(notNullValue()));
-        assertThat(throwableRef.get(), is(t));
+        assertThat(throwableRef.get(), is(e));
         assertThat(responseRef.get(), is(nullValue()));
     }
 
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportPutRoleActionTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportPutRoleActionTests.java
index 3a7150e4679..6ea5bf6b25c 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportPutRoleActionTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/role/TransportPutRoleActionTests.java
@@ -56,7 +56,7 @@ public class TransportPutRoleActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -97,7 +97,7 @@ public class TransportPutRoleActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -109,7 +109,7 @@ public class TransportPutRoleActionTests extends ESTestCase {
     }
 
     public void testException() {
-        final Throwable t = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException());
+        final Exception e = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException());
         final String roleName = randomFrom("admin", "dept_a", "restricted");
         NativeRolesStore rolesStore = mock(NativeRolesStore.class);
         TransportPutRoleAction action = new TransportPutRoleAction(Settings.EMPTY, mock(ThreadPool.class), mock(ActionFilters.class),
@@ -124,7 +124,7 @@ public class TransportPutRoleActionTests extends ESTestCase {
                 Object[] args = invocation.getArguments();
                 assert args.length == 3;
                 ActionListener<Boolean> listener = (ActionListener<Boolean>) args[2];
-                listener.onFailure(t);
+                listener.onFailure(e);
                 return null;
             }
         }).when(rolesStore).putRole(eq(request), any(RoleDescriptor.class), any(ActionListener.class));
@@ -138,14 +138,14 @@ public class TransportPutRoleActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
 
         assertThat(responseRef.get(), is(nullValue()));
         assertThat(throwableRef.get(), is(notNullValue()));
-        assertThat(throwableRef.get(), is(sameInstance(t)));
+        assertThat(throwableRef.get(), is(sameInstance(e)));
         verify(rolesStore, times(1)).putRole(eq(request), any(RoleDescriptor.class), any(ActionListener.class));
     }
 }
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportAuthenticateActionTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportAuthenticateActionTests.java
index e7b820642a9..236dce76b97 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportAuthenticateActionTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportAuthenticateActionTests.java
@@ -47,7 +47,7 @@ public class TransportAuthenticateActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -72,7 +72,7 @@ public class TransportAuthenticateActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -99,7 +99,7 @@ public class TransportAuthenticateActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportChangePasswordActionTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportChangePasswordActionTests.java
index 450e53caf65..35344ba2394 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportChangePasswordActionTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportChangePasswordActionTests.java
@@ -68,7 +68,7 @@ public class TransportChangePasswordActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -97,7 +97,7 @@ public class TransportChangePasswordActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -135,7 +135,7 @@ public class TransportChangePasswordActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -152,13 +152,13 @@ public class TransportChangePasswordActionTests extends ESTestCase {
         ChangePasswordRequest request = new ChangePasswordRequest();
         request.username(user.principal());
         request.passwordHash(Hasher.BCRYPT.hash(new SecuredString("changeme".toCharArray())));
-        final Throwable t = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException(), new RuntimeException());
+        final Exception e = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException(), new RuntimeException());
         doAnswer(new Answer() {
             public Void answer(InvocationOnMock invocation) {
                 Object[] args = invocation.getArguments();
                 assert args.length == 2;
                 ActionListener<Void> listener = (ActionListener<Void>) args[1];
-                listener.onFailure(t);
+                listener.onFailure(e);
                 return null;
             }
         }).when(usersStore).changePassword(eq(request), any(ActionListener.class));
@@ -174,14 +174,14 @@ public class TransportChangePasswordActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
 
         assertThat(responseRef.get(), is(nullValue()));
         assertThat(throwableRef.get(), is(notNullValue()));
-        assertThat(throwableRef.get(), sameInstance(t));
+        assertThat(throwableRef.get(), sameInstance(e));
         verify(usersStore, times(1)).changePassword(eq(request), any(ActionListener.class));
     }
 }
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportDeleteUserActionTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportDeleteUserActionTests.java
index 9735a698e8b..614681491df 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportDeleteUserActionTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportDeleteUserActionTests.java
@@ -63,7 +63,7 @@ public class TransportDeleteUserActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -90,7 +90,7 @@ public class TransportDeleteUserActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -118,7 +118,7 @@ public class TransportDeleteUserActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -156,7 +156,7 @@ public class TransportDeleteUserActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -168,7 +168,7 @@ public class TransportDeleteUserActionTests extends ESTestCase {
     }
 
     public void testException() {
-        final Throwable t = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException(), new RuntimeException());
+        final Exception e = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException(), new RuntimeException());
         final User user = new User("joe");
         NativeUsersStore usersStore = mock(NativeUsersStore.class);
         TransportDeleteUserAction action = new TransportDeleteUserAction(Settings.EMPTY, mock(ThreadPool.class),
@@ -180,7 +180,7 @@ public class TransportDeleteUserActionTests extends ESTestCase {
                 Object[] args = invocation.getArguments();
                 assert args.length == 2;
                 ActionListener<Boolean> listener = (ActionListener<Boolean>) args[1];
-                listener.onFailure(t);
+                listener.onFailure(e);
                 return null;
             }
         }).when(usersStore).deleteUser(eq(request), any(ActionListener.class));
@@ -194,14 +194,14 @@ public class TransportDeleteUserActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
 
         assertThat(responseRef.get(), is(nullValue()));
         assertThat(throwableRef.get(), is(notNullValue()));
-        assertThat(throwableRef.get(), sameInstance(t));
+        assertThat(throwableRef.get(), sameInstance(e));
         verify(usersStore, times(1)).deleteUser(eq(request), any(ActionListener.class));
     }
 }
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportGetUsersActionTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportGetUsersActionTests.java
index 4d8e0e32c37..c5573602968 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportGetUsersActionTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportGetUsersActionTests.java
@@ -84,7 +84,7 @@ public class TransportGetUsersActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -116,7 +116,7 @@ public class TransportGetUsersActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -147,7 +147,7 @@ public class TransportGetUsersActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -185,7 +185,7 @@ public class TransportGetUsersActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -242,7 +242,7 @@ public class TransportGetUsersActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -261,7 +261,7 @@ public class TransportGetUsersActionTests extends ESTestCase {
     }
 
     public void testException() {
-        final Throwable t = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException(), new ValidationException());
+        final Exception e = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException(), new ValidationException());
         final List<User> storeUsers =
                 randomFrom(Collections.singletonList(new User("joe")), Arrays.asList(new User("jane"), new User("fred")), randomUsers());
         final String[] storeUsernames = storeUsers.stream().map(User::principal).collect(Collectors.toList()).toArray(Strings.EMPTY_ARRAY);
@@ -277,7 +277,7 @@ public class TransportGetUsersActionTests extends ESTestCase {
                     Object[] args = invocation.getArguments();
                     assert args.length == 2;
                     ActionListener<List<User>> listener = (ActionListener<List<User>>) args[1];
-                    listener.onFailure(t);
+                    listener.onFailure(e);
                     return null;
                 }
             }).when(usersStore).getUsers(aryEq(storeUsernames), any(ActionListener.class));
@@ -288,7 +288,7 @@ public class TransportGetUsersActionTests extends ESTestCase {
                     Object[] args = invocation.getArguments();
                     assert args.length == 2;
                     ActionListener<User> listener = (ActionListener<User>) args[1];
-                    listener.onFailure(t);
+                    listener.onFailure(e);
                     return null;
                 }
             }).when(usersStore).getUser(eq(storeUsernames[0]), any(ActionListener.class));
@@ -303,13 +303,13 @@ public class TransportGetUsersActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
 
         assertThat(throwableRef.get(), is(notNullValue()));
-        assertThat(throwableRef.get(), is(sameInstance(t)));
+        assertThat(throwableRef.get(), is(sameInstance(e)));
         assertThat(responseRef.get(), is(nullValue()));
         if (request.usernames().length == 1) {
             verify(usersStore, times(1)).getUser(eq(request.usernames()[0]), any(ActionListener.class));
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportPutUserActionTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportPutUserActionTests.java
index a99e0f9da00..52b7a2e247f 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportPutUserActionTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/action/user/TransportPutUserActionTests.java
@@ -67,7 +67,7 @@ public class TransportPutUserActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -95,7 +95,7 @@ public class TransportPutUserActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -124,7 +124,7 @@ public class TransportPutUserActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -167,7 +167,7 @@ public class TransportPutUserActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
@@ -179,7 +179,7 @@ public class TransportPutUserActionTests extends ESTestCase {
     }
 
     public void testException() {
-        final Throwable t = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException(), new ValidationException());
+        final Exception e = randomFrom(new ElasticsearchSecurityException(""), new IllegalStateException(), new ValidationException());
         final User user = new User("joe");
         NativeUsersStore usersStore = mock(NativeUsersStore.class);
         TransportPutUserAction action = new TransportPutUserAction(Settings.EMPTY, mock(ThreadPool.class),
@@ -192,7 +192,7 @@ public class TransportPutUserActionTests extends ESTestCase {
                 Object[] args = invocation.getArguments();
                 assert args.length == 2;
                 ActionListener<Boolean> listener = (ActionListener<Boolean>) args[1];
-                listener.onFailure(t);
+                listener.onFailure(e);
                 return null;
             }
         }).when(usersStore).putUser(eq(request), any(ActionListener.class));
@@ -206,14 +206,14 @@ public class TransportPutUserActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 throwableRef.set(e);
             }
         });
 
         assertThat(responseRef.get(), is(nullValue()));
         assertThat(throwableRef.get(), is(notNullValue()));
-        assertThat(throwableRef.get(), sameInstance(t));
+        assertThat(throwableRef.get(), sameInstance(e));
         verify(usersStore, times(1)).putUser(eq(request), any(ActionListener.class));
     }
 }
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/audit/AuditTrailModuleTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/audit/AuditTrailModuleTests.java
index 9072197572d..660304b31b7 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/audit/AuditTrailModuleTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/audit/AuditTrailModuleTests.java
@@ -5,7 +5,6 @@
  */
 package org.elasticsearch.xpack.security.audit;
 
-import org.elasticsearch.Version;
 import org.elasticsearch.common.inject.Guice;
 import org.elasticsearch.common.inject.Injector;
 import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
@@ -15,20 +14,17 @@ import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.settings.SettingsModule;
 import org.elasticsearch.indices.breaker.CircuitBreakerService;
 import org.elasticsearch.node.Node;
-import org.elasticsearch.xpack.security.audit.logfile.LoggingAuditTrail;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.threadpool.TestThreadPool;
 import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.transport.Transport;
 import org.elasticsearch.transport.local.LocalTransport;
+import org.elasticsearch.xpack.security.audit.logfile.LoggingAuditTrail;
 
 import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
 
-/**
- *
- */
 public class AuditTrailModuleTests extends ESTestCase {
     public void testEnabled() throws Exception {
         Settings settings = Settings.builder()
@@ -93,7 +89,7 @@ public class AuditTrailModuleTests extends ESTestCase {
         try {
             Guice.createInjector(settingsModule, new AuditTrailModule(settings));
             fail("Expect initialization to fail when an unknown audit trail output is configured");
-        } catch (Throwable t) {
+        } catch (Exception e) {
             // expected
         }
     }
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/authc/file/FileUserRolesStoreTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/authc/file/FileUserRolesStoreTests.java
index 43826371603..67285e81451 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/authc/file/FileUserRolesStoreTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/authc/file/FileUserRolesStoreTests.java
@@ -49,9 +49,6 @@ import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 
-/**
- *
- */
 public class FileUserRolesStoreTests extends ESTestCase {
     private Settings settings;
     private Environment env;
@@ -217,8 +214,8 @@ public class FileUserRolesStoreTests extends ESTestCase {
         try {
             FileUserRolesStore.parseFile(file, logger);
             fail("expected a parse failure");
-        } catch (Throwable t) {
-            this.logger.info("expected", t);
+        } catch (Exception e) {
+            this.logger.info("expected", e);
         }
     }
 
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/authc/ldap/LdapSessionFactoryTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/authc/ldap/LdapSessionFactoryTests.java
index e745513984f..f4550255b1a 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/authc/ldap/LdapSessionFactoryTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/authc/ldap/LdapSessionFactoryTests.java
@@ -56,9 +56,9 @@ public class LdapSessionFactoryTests extends LdapTestCase {
         ldapServer.setProcessingDelayMillis(500L);
         try (LdapSession session = sessionFactory.session(user, userPass)) {
             fail("expected connection timeout error here");
-        } catch (Throwable t) {
-            assertThat(t, instanceOf(ElasticsearchSecurityException.class));
-            assertThat(t.getCause().getMessage(), containsString("A client-side timeout was encountered while waiting "));
+        } catch (Exception e) {
+            assertThat(e, instanceOf(ElasticsearchSecurityException.class));
+            assertThat(e.getCause().getMessage(), containsString("A client-side timeout was encountered while waiting "));
         } finally {
             ldapServer.setProcessingDelayMillis(0L);
         }
@@ -85,11 +85,11 @@ public class LdapSessionFactoryTests extends LdapTestCase {
         long start = System.currentTimeMillis();
         try (LdapSession session = sessionFactory.session(user, userPass)) {
             fail("expected connection timeout error here");
-        } catch (Throwable t) {
+        } catch (Exception e) {
             long time = System.currentTimeMillis() - start;
             assertThat(time, lessThan(10000L));
-            assertThat(t, instanceOf(IOException.class));
-            assertThat(t.getCause().getCause().getMessage(), containsString("within the configured timeout of"));
+            assertThat(e, instanceOf(IOException.class));
+            assertThat(e.getCause().getCause().getMessage(), containsString("within the configured timeout of"));
         }
     }
 
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/support/SelfReschedulingRunnableTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/support/SelfReschedulingRunnableTests.java
index b81b879e09f..c871da38ea8 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/support/SelfReschedulingRunnableTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/support/SelfReschedulingRunnableTests.java
@@ -55,7 +55,7 @@ public class SelfReschedulingRunnableTests extends ESTestCase {
         final ThreadPool threadPool = mock(ThreadPool.class);
         final AbstractRunnable runnable = new AbstractRunnable() {
             @Override
-            public void onFailure(Throwable throwable) {
+            public void onFailure(Exception throwable) {
             }
 
             @Override
@@ -88,7 +88,7 @@ public class SelfReschedulingRunnableTests extends ESTestCase {
         final CountDownLatch pauseLatch = new CountDownLatch(1);
         final AbstractRunnable runnable = new AbstractRunnable() {
             @Override
-            public void onFailure(Throwable throwable) {
+            public void onFailure(Exception throwable) {
             }
 
             @Override
@@ -195,7 +195,7 @@ public class SelfReschedulingRunnableTests extends ESTestCase {
         final AtomicInteger runCounter = new AtomicInteger(0);
         final AbstractRunnable runnable = new AbstractRunnable() {
             @Override
-            public void onFailure(Throwable throwable) {
+            public void onFailure(Exception throwable) {
                 failureCounter.incrementAndGet();
             }
 
@@ -238,7 +238,7 @@ public class SelfReschedulingRunnableTests extends ESTestCase {
         final CountDownLatch stopCalledLatch = new CountDownLatch(1);
         final AbstractRunnable runnable = new AbstractRunnable() {
             @Override
-            public void onFailure(Throwable throwable) {
+            public void onFailure(Exception throwable) {
                 throw new IllegalStateException("we should never be in this method!");
             }
 
diff --git a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/transport/netty/HandshakeWaitingHandlerTests.java b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/transport/netty/HandshakeWaitingHandlerTests.java
index f54934556d9..e848eb44f3d 100644
--- a/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/transport/netty/HandshakeWaitingHandlerTests.java
+++ b/elasticsearch/x-pack/security/src/test/java/org/elasticsearch/xpack/security/transport/netty/HandshakeWaitingHandlerTests.java
@@ -192,13 +192,13 @@ public class HandshakeWaitingHandlerTests extends ESTestCase {
             try {
                 serverBootstrap.bind(new InetSocketAddress(InetAddress.getLoopbackAddress(), randomPort));
                 break;
-            } catch (Throwable t) {
-                if (t.getCause() instanceof BindException) {
+            } catch (Exception e) {
+                if (e.getCause() instanceof BindException) {
                     logger.error("Tried to bind to port [{}], going to retry", randomPort);
                     randomPort = randomIntBetween(49000, 65500);
                 }
                 if (tries >= maxTries) {
-                    throw new RuntimeException("Failed to start server bootstrap [" + tries + "] times, stopping", t);
+                    throw new RuntimeException("Failed to start server bootstrap [" + tries + "] times, stopping", e);
                 }
                 tries++;
             }
diff --git a/elasticsearch/x-pack/src/main/java/org/elasticsearch/xpack/extensions/XPackExtensionsService.java b/elasticsearch/x-pack/src/main/java/org/elasticsearch/xpack/extensions/XPackExtensionsService.java
index 922b86e47de..4c9d903f1de 100644
--- a/elasticsearch/x-pack/src/main/java/org/elasticsearch/xpack/extensions/XPackExtensionsService.java
+++ b/elasticsearch/x-pack/src/main/java/org/elasticsearch/xpack/extensions/XPackExtensionsService.java
@@ -28,9 +28,6 @@ import java.util.Arrays;
 
 import static org.elasticsearch.common.io.FileSystemUtils.isAccessibleDirectory;
 
-/**
- *
- */
 public class XPackExtensionsService {
     private final Settings settings;
 
@@ -186,7 +183,7 @@ public class XPackExtensionsService {
                             "Settings instance");
                 }
             }
-        } catch (Throwable e) {
+        } catch (Exception e) {
             throw new ElasticsearchException("Failed to load extension class [" + extClass.getName() + "]", e);
         }
     }
diff --git a/elasticsearch/x-pack/src/test/java/org/elasticsearch/xpack/action/TransportXPackInfoActionTests.java b/elasticsearch/x-pack/src/test/java/org/elasticsearch/xpack/action/TransportXPackInfoActionTests.java
index 77318043924..fc3b5faf986 100644
--- a/elasticsearch/x-pack/src/test/java/org/elasticsearch/xpack/action/TransportXPackInfoActionTests.java
+++ b/elasticsearch/x-pack/src/test/java/org/elasticsearch/xpack/action/TransportXPackInfoActionTests.java
@@ -105,7 +105,7 @@ public class TransportXPackInfoActionTests extends ESTestCase {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 error.set(e);
                 latch.countDown();
             }
diff --git a/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/WatcherLifeCycleService.java b/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/WatcherLifeCycleService.java
index 5c96c3a3daa..2b3576c27a6 100644
--- a/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/WatcherLifeCycleService.java
+++ b/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/WatcherLifeCycleService.java
@@ -166,7 +166,7 @@ public class WatcherLifeCycleService extends AbstractComponent implements Cluste
             }
 
             @Override
-            public void onFailure(Throwable throwable) {
+            public void onFailure(Exception throwable) {
                 logger.warn("updating manually stopped isn't acked", throwable);
                 latch.countDown();
             }
@@ -199,7 +199,7 @@ public class WatcherLifeCycleService extends AbstractComponent implements Cluste
             }
 
             @Override
-            public void onFailure(String source, Throwable throwable) {
+            public void onFailure(String source, Exception throwable) {
                 latch.countDown();
                 logger.warn("couldn't update watcher metadata [{}]", throwable, source);
             }
diff --git a/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/execution/ExecutionService.java b/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/execution/ExecutionService.java
index 219f7941586..488f1a51c9f 100644
--- a/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/execution/ExecutionService.java
+++ b/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/execution/ExecutionService.java
@@ -206,7 +206,7 @@ public class ExecutionService extends AbstractComponent {
             }
 
             @Override
-            public void onFailure(Throwable e) {
+            public void onFailure(Exception e) {
                 Throwable cause = ExceptionsHelper.unwrapCause(e);
                 if (cause instanceof EsRejectedExecutionException) {
                     logger.debug("failed to store watch records due to overloaded threadpool [{}]", ExceptionsHelper.detailedMessage(e));
diff --git a/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/execution/TriggeredWatchStore.java b/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/execution/TriggeredWatchStore.java
index 0f5a19aa312..e5619f2096c 100644
--- a/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/execution/TriggeredWatchStore.java
+++ b/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/execution/TriggeredWatchStore.java
@@ -125,7 +125,7 @@ public class TriggeredWatchStore extends AbstractComponent {
                 }
 
                 @Override
-                public void onFailure(Throwable e) {
+                public void onFailure(Exception e) {
                     listener.onFailure(e);
                 }
             });
@@ -149,7 +149,7 @@ public class TriggeredWatchStore extends AbstractComponent {
                 }
 
                 @Override
-                public void onFailure(Throwable e) {
+                public void onFailure(Exception e) {
                     listener.onFailure(e);
                 }
             });
@@ -183,7 +183,7 @@ public class TriggeredWatchStore extends AbstractComponent {
                 }
 
                 @Override
-                public void onFailure(Throwable e) {
+                public void onFailure(Exception e) {
                     listener.onFailure(e);
                 }
             });
diff --git a/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/support/SearchRequestEquivalence.java b/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/support/SearchRequestEquivalence.java
index fec055628f1..f4e40a59817 100644
--- a/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/support/SearchRequestEquivalence.java
+++ b/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/support/SearchRequestEquivalence.java
@@ -42,8 +42,8 @@ public final class SearchRequestEquivalence {
             r2.writeTo(output1);
             byte[] bytes2 = BytesReference.toBytes(output1.bytes());
             return Arrays.equals(bytes1, bytes2);
-        } catch (Throwable t) {
-            throw illegalState("could not compare search requests", t);
+        } catch (Exception e) {
+            throw illegalState("could not compare search requests", e);
         }
     }
 }
diff --git a/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/transport/actions/get/TransportGetWatchAction.java b/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/transport/actions/get/TransportGetWatchAction.java
index cb581d5c470..224f56052f3 100644
--- a/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/transport/actions/get/TransportGetWatchAction.java
+++ b/elasticsearch/x-pack/watcher/src/main/java/org/elasticsearch/xpack/watcher/transport/actions/get/TransportGetWatchAction.java
@@ -85,9 +85,9 @@ public class TransportGetWatchAction extends WatcherTransportAction<GetWatchRequ
                 listener.onFailure(e);
             }
 
-        } catch (Throwable t) {
-            logger.error("failed to get watch [{}]", t, request.getId());
-            throw t;
+        } catch (Exception e) {
+            logger.error("failed to get watch [{}]", e, request.getId());
+            throw e;
         }
     }
 
diff --git a/elasticsearch/x-pack/watcher/src/test/java/org/elasticsearch/xpack/watcher/execution/ManualExecutionTests.java b/elasticsearch/x-pack/watcher/src/test/java/org/elasticsearch/xpack/watcher/execution/ManualExecutionTests.java
index 30f2e8127df..084a52b78a4 100644
--- a/elasticsearch/x-pack/watcher/src/test/java/org/elasticsearch/xpack/watcher/execution/ManualExecutionTests.java
+++ b/elasticsearch/x-pack/watcher/src/test/java/org/elasticsearch/xpack/watcher/execution/ManualExecutionTests.java
@@ -332,8 +332,8 @@ public class ManualExecutionTests extends AbstractWatcherIntegrationTestCase {
                 WatchRecord record = executionService.execute(ctxBuilder.build());
                 assertThat(record, notNullValue());
                 assertThat(record.state(), is(ExecutionState.NOT_EXECUTED_WATCH_MISSING));
-            } catch (Throwable t) {
-                throw new ElasticsearchException("Failure mode execution of [{}] failed in an unexpected way", t, watchId);
+            } catch (Exception e) {
+                throw new ElasticsearchException("Failure mode execution of [{}] failed in an unexpected way", e, watchId);
             }
         }
     }