diff --git a/buildSrc/src/main/resources/checkstyle_suppressions.xml b/buildSrc/src/main/resources/checkstyle_suppressions.xml
index 2cdb0f74f6d..8394e430777 100644
--- a/buildSrc/src/main/resources/checkstyle_suppressions.xml
+++ b/buildSrc/src/main/resources/checkstyle_suppressions.xml
@@ -30,8 +30,6 @@
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]node[/\\]info[/\\]TransportNodesInfoAction.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]node[/\\]stats[/\\]NodesStatsRequestBuilder.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]node[/\\]stats[/\\]TransportNodesStatsAction.java" checks="LineLength" />
-  <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]node[/\\]tasks[/\\]list[/\\]ListTasksResponse.java" checks="LineLength" />
-  <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]node[/\\]tasks[/\\]list[/\\]TransportListTasksAction.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]repositories[/\\]delete[/\\]DeleteRepositoryRequestBuilder.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]repositories[/\\]delete[/\\]TransportDeleteRepositoryAction.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]repositories[/\\]get[/\\]GetRepositoriesRequestBuilder.java" checks="LineLength" />
@@ -233,8 +231,6 @@
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]support[/\\]single[/\\]shard[/\\]SingleShardOperationRequestBuilder.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]support[/\\]single[/\\]shard[/\\]SingleShardRequest.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]support[/\\]single[/\\]shard[/\\]TransportSingleShardAction.java" checks="LineLength" />
-  <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]support[/\\]tasks[/\\]TasksRequestBuilder.java" checks="LineLength" />
-  <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]support[/\\]tasks[/\\]TransportTasksAction.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]termvectors[/\\]MultiTermVectorsRequest.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]termvectors[/\\]MultiTermVectorsRequestBuilder.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]termvectors[/\\]TermVectorsRequest.java" checks="LineLength" />
@@ -803,7 +799,6 @@
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]RejectionActionIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]HotThreadsIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]health[/\\]ClusterHealthResponsesTests.java" checks="LineLength" />
-  <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]node[/\\]tasks[/\\]TransportTasksActionTests.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]repositories[/\\]RepositoryBlocksIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]settings[/\\]SettingsUpdaterTests.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]snapshots[/\\]SnapshotBlocksIT.java" checks="LineLength" />
@@ -1467,7 +1462,6 @@
   <suppress files="test[/\\]framework[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]test[/\\]rest[/\\]test[/\\]RestTestParserTests.java" checks="LineLength" />
   <suppress files="test[/\\]framework[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]test[/\\]test[/\\]InternalTestClusterTests.java" checks="LineLength" />
 
-  <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]node[/\\]tasks[/\\]list[/\\]TaskInfo.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]common[/\\]cli[/\\]CliTool.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]common[/\\]settings[/\\]SettingsModule.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]rest[/\\]action[/\\]admin[/\\]indices[/\\]settings[/\\]RestGetSettingsAction.java" checks="LineLength" />
@@ -1476,6 +1470,5 @@
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]rest[/\\]CorsNotSetIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]common[/\\]settings[/\\]SettingsModuleTests.java" checks="LineLength" />
   <suppress files="plugins[/\\]store-smb[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]index[/\\]store[/\\]SmbDirectoryWrapper.java" checks="LineLength" />
-  <suppress files="test[/\\]framework[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]test[/\\]tasks[/\\]MockTaskManager.java" checks="LineLength" />
   <suppress files="test[/\\]framework[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]common[/\\]inject[/\\]ModuleTestCase.java" checks="LineLength" />
 </suppressions>
diff --git a/core/src/main/java/org/elasticsearch/action/admin/cluster/node/tasks/list/ListTasksResponse.java b/core/src/main/java/org/elasticsearch/action/admin/cluster/node/tasks/list/ListTasksResponse.java
index f8ecd7a506f..446ae3affb7 100644
--- a/core/src/main/java/org/elasticsearch/action/admin/cluster/node/tasks/list/ListTasksResponse.java
+++ b/core/src/main/java/org/elasticsearch/action/admin/cluster/node/tasks/list/ListTasksResponse.java
@@ -23,11 +23,11 @@ import org.elasticsearch.action.FailedNodeException;
 import org.elasticsearch.action.TaskOperationFailure;
 import org.elasticsearch.action.support.tasks.BaseTasksResponse;
 import org.elasticsearch.cluster.node.DiscoveryNode;
+import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.xcontent.ToXContent;
 import org.elasticsearch.common.xcontent.XContentBuilder;
-import org.elasticsearch.common.xcontent.XContentFactory;
 import org.elasticsearch.tasks.TaskId;
 
 import java.io.IOException;
@@ -54,7 +54,8 @@ public class ListTasksResponse extends BaseTasksResponse implements ToXContent {
     public ListTasksResponse() {
     }
 
-    public ListTasksResponse(List<TaskInfo> tasks, List<TaskOperationFailure> taskFailures, List<? extends FailedNodeException> nodeFailures) {
+    public ListTasksResponse(List<TaskInfo> tasks, List<TaskOperationFailure> taskFailures,
+            List<? extends FailedNodeException> nodeFailures) {
         super(taskFailures, nodeFailures);
         this.tasks = tasks == null ? Collections.emptyList() : Collections.unmodifiableList(new ArrayList<>(tasks));
     }
@@ -205,14 +206,6 @@ public class ListTasksResponse extends BaseTasksResponse implements ToXContent {
 
     @Override
     public String toString() {
-        try {
-            XContentBuilder builder = XContentFactory.jsonBuilder().prettyPrint();
-            builder.startObject();
-            toXContent(builder, EMPTY_PARAMS);
-            builder.endObject();
-            return builder.string();
-        } catch (IOException e) {
-            return "{ \"error\" : \"" + e.getMessage() + "\"}";
-        }
+        return Strings.toString(this);
     }
 }
diff --git a/core/src/main/java/org/elasticsearch/action/admin/cluster/node/tasks/list/TransportListTasksAction.java b/core/src/main/java/org/elasticsearch/action/admin/cluster/node/tasks/list/TransportListTasksAction.java
index e6ea002a794..b05049f6776 100644
--- a/core/src/main/java/org/elasticsearch/action/admin/cluster/node/tasks/list/TransportListTasksAction.java
+++ b/core/src/main/java/org/elasticsearch/action/admin/cluster/node/tasks/list/TransportListTasksAction.java
@@ -51,12 +51,15 @@ public class TransportListTasksAction extends TransportTasksAction<Task, ListTas
     private static final TimeValue DEFAULT_WAIT_FOR_COMPLETION_TIMEOUT = timeValueSeconds(30);
 
     @Inject
-    public TransportListTasksAction(Settings settings, ClusterName clusterName, ThreadPool threadPool, ClusterService clusterService, TransportService transportService, ActionFilters actionFilters, IndexNameExpressionResolver indexNameExpressionResolver) {
-        super(settings, ListTasksAction.NAME, clusterName, threadPool, clusterService, transportService, actionFilters, indexNameExpressionResolver, ListTasksRequest::new, ListTasksResponse::new, ThreadPool.Names.MANAGEMENT);
+    public TransportListTasksAction(Settings settings, ClusterName clusterName, ThreadPool threadPool, ClusterService clusterService,
+            TransportService transportService, ActionFilters actionFilters, IndexNameExpressionResolver indexNameExpressionResolver) {
+        super(settings, ListTasksAction.NAME, clusterName, threadPool, clusterService, transportService, actionFilters,
+                indexNameExpressionResolver, ListTasksRequest::new, ListTasksResponse::new, ThreadPool.Names.MANAGEMENT);
     }
 
     @Override
-    protected ListTasksResponse newResponse(ListTasksRequest request, List<TaskInfo> tasks, List<TaskOperationFailure> taskOperationFailures, List<FailedNodeException> failedNodeExceptions) {
+    protected ListTasksResponse newResponse(ListTasksRequest request, List<TaskInfo> tasks,
+            List<TaskOperationFailure> taskOperationFailures, List<FailedNodeException> failedNodeExceptions) {
         return new ListTasksResponse(tasks, taskOperationFailures, failedNodeExceptions);
     }
 
diff --git a/core/src/main/java/org/elasticsearch/action/support/tasks/TasksRequestBuilder.java b/core/src/main/java/org/elasticsearch/action/support/tasks/TasksRequestBuilder.java
index a510a847c62..78a2de20a89 100644
--- a/core/src/main/java/org/elasticsearch/action/support/tasks/TasksRequestBuilder.java
+++ b/core/src/main/java/org/elasticsearch/action/support/tasks/TasksRequestBuilder.java
@@ -26,8 +26,11 @@ import org.elasticsearch.common.unit.TimeValue;
 /**
  * Builder for task-based requests
  */
-public class TasksRequestBuilder <Request extends BaseTasksRequest<Request>, Response extends BaseTasksResponse, RequestBuilder extends TasksRequestBuilder<Request, Response, RequestBuilder>>
-        extends ActionRequestBuilder<Request, Response, RequestBuilder> {
+public class TasksRequestBuilder<
+            Request extends BaseTasksRequest<Request>,
+            Response extends BaseTasksResponse,
+            RequestBuilder extends TasksRequestBuilder<Request, Response, RequestBuilder>
+        > extends ActionRequestBuilder<Request, Response, RequestBuilder> {
 
     protected TasksRequestBuilder(ElasticsearchClient client, Action<Request, Response, RequestBuilder> action, Request request) {
         super(client, action, request);
diff --git a/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/CancellableTasksTests.java b/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/CancellableTasksTests.java
index fdbc16916ce..d96531b2f6c 100644
--- a/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/CancellableTasksTests.java
+++ b/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/CancellableTasksTests.java
@@ -202,7 +202,7 @@ public class CancellableTasksTests extends TaskManagerTestCase {
         for (int i = 0; i < testNodes.length; i++) {
             boolean shouldBlock = blockOnNodes.contains(testNodes[i]);
             logger.info("The action in the node [{}] should block: [{}]", testNodes[i].discoveryNode.getId(), shouldBlock);
-            actions[i] = new CancellableTestNodesAction(Settings.EMPTY, "testAction", clusterName, threadPool, testNodes[i]
+            actions[i] = new CancellableTestNodesAction(Settings.EMPTY, "testAction", CLUSTER_NAME, threadPool, testNodes[i]
                 .clusterService, testNodes[i].transportService, shouldBlock, actionLatch);
         }
         Task task = actions[0].execute(request, listener);
diff --git a/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/TaskManagerTestCase.java b/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/TaskManagerTestCase.java
index 9153e659d0b..0490dfd96aa 100644
--- a/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/TaskManagerTestCase.java
+++ b/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/TaskManagerTestCase.java
@@ -68,7 +68,7 @@ import static org.elasticsearch.cluster.service.ClusterServiceUtils.setState;
 public abstract class TaskManagerTestCase extends ESTestCase {
 
     protected static ThreadPool threadPool;
-    public static final ClusterName clusterName = new ClusterName("test-cluster");
+    public static final ClusterName CLUSTER_NAME = new ClusterName("test-cluster");
     protected TestNode[] testNodes;
     protected int nodesCount;
 
@@ -203,10 +203,10 @@ public abstract class TaskManagerTestCase extends ESTestCase {
                     emptyMap(), emptySet(), Version.CURRENT);
             IndexNameExpressionResolver indexNameExpressionResolver = new IndexNameExpressionResolver(settings);
             ActionFilters actionFilters = new ActionFilters(emptySet());
-            transportListTasksAction = new TransportListTasksAction(settings, clusterName, threadPool, clusterService, transportService,
-                    actionFilters, indexNameExpressionResolver);
-            transportCancelTasksAction = new TransportCancelTasksAction(settings, clusterName, threadPool, clusterService, transportService,
+            transportListTasksAction = new TransportListTasksAction(settings, CLUSTER_NAME, threadPool, clusterService, transportService,
                     actionFilters, indexNameExpressionResolver);
+            transportCancelTasksAction = new TransportCancelTasksAction(settings, CLUSTER_NAME, threadPool, clusterService,
+                    transportService, actionFilters, indexNameExpressionResolver);
             transportService.acceptIncomingRequests();
         }
 
diff --git a/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/TransportTasksActionTests.java b/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/TransportTasksActionTests.java
index 6e0bf27e642..3e996421441 100644
--- a/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/TransportTasksActionTests.java
+++ b/core/src/test/java/org/elasticsearch/action/admin/cluster/node/tasks/TransportTasksActionTests.java
@@ -221,7 +221,8 @@ public class TransportTasksActionTests extends TaskManagerTestCase {
 
         }
 
-        public TestTasksResponse(List<TestTaskResponse> tasks, List<TaskOperationFailure> taskFailures, List<? extends FailedNodeException> nodeFailures) {
+        public TestTasksResponse(List<TestTaskResponse> tasks, List<TaskOperationFailure> taskFailures,
+                List<? extends FailedNodeException> nodeFailures) {
             super(taskFailures, nodeFailures);
             this.tasks = tasks == null ? Collections.emptyList() : Collections.unmodifiableList(new ArrayList<>(tasks));
         }
@@ -252,14 +253,16 @@ public class TransportTasksActionTests extends TaskManagerTestCase {
      */
     static abstract class TestTasksAction extends TransportTasksAction<Task, TestTasksRequest, TestTasksResponse, TestTaskResponse> {
 
-        protected TestTasksAction(Settings settings, String actionName, ClusterName clusterName, ThreadPool threadPool, ClusterService clusterService,
-                                  TransportService transportService) {
-            super(settings, actionName, clusterName, threadPool, clusterService, transportService, new ActionFilters(new HashSet<>()), new IndexNameExpressionResolver(Settings.EMPTY),
-                TestTasksRequest::new, TestTasksResponse::new, ThreadPool.Names.MANAGEMENT);
+        protected TestTasksAction(Settings settings, String actionName, ClusterName clusterName, ThreadPool threadPool,
+                ClusterService clusterService, TransportService transportService) {
+            super(settings, actionName, clusterName, threadPool, clusterService, transportService, new ActionFilters(new HashSet<>()),
+                    new IndexNameExpressionResolver(Settings.EMPTY), TestTasksRequest::new, TestTasksResponse::new,
+                    ThreadPool.Names.MANAGEMENT);
         }
 
         @Override
-        protected TestTasksResponse newResponse(TestTasksRequest request, List<TestTaskResponse> tasks, List<TaskOperationFailure> taskOperationFailures, List<FailedNodeException> failedNodeExceptions) {
+        protected TestTasksResponse newResponse(TestTasksRequest request, List<TestTaskResponse> tasks,
+                List<TaskOperationFailure> taskOperationFailures, List<FailedNodeException> failedNodeExceptions) {
             return new TestTasksResponse(tasks, taskOperationFailures, failedNodeExceptions);
         }
 
@@ -278,22 +281,26 @@ public class TransportTasksActionTests extends TaskManagerTestCase {
         return startBlockingTestNodesAction(checkLatch, new NodesRequest("Test Request"));
     }
 
-    private ActionFuture<NodesResponse> startBlockingTestNodesAction(CountDownLatch checkLatch,  NodesRequest request) throws InterruptedException {
+    private ActionFuture<NodesResponse> startBlockingTestNodesAction(CountDownLatch checkLatch, NodesRequest request)
+            throws InterruptedException {
         PlainActionFuture<NodesResponse> future = newFuture();
         startBlockingTestNodesAction(checkLatch, request, future);
         return future;
     }
 
-    private Task startBlockingTestNodesAction(CountDownLatch checkLatch, ActionListener<NodesResponse> listener) throws InterruptedException {
+    private Task startBlockingTestNodesAction(CountDownLatch checkLatch, ActionListener<NodesResponse> listener)
+            throws InterruptedException {
         return startBlockingTestNodesAction(checkLatch, new NodesRequest("Test Request"), listener);
     }
 
-    private Task startBlockingTestNodesAction(CountDownLatch checkLatch, NodesRequest request,  ActionListener<NodesResponse> listener) throws InterruptedException {
+    private Task startBlockingTestNodesAction(CountDownLatch checkLatch, NodesRequest request, ActionListener<NodesResponse> listener)
+            throws InterruptedException {
         CountDownLatch actionLatch = new CountDownLatch(nodesCount);
         TestNodesAction[] actions = new TestNodesAction[nodesCount];
         for (int i = 0; i < testNodes.length; i++) {
             final int node = i;
-            actions[i] = new TestNodesAction(Settings.EMPTY, "testAction", clusterName, threadPool, testNodes[i].clusterService, testNodes[i].transportService) {
+            actions[i] = new TestNodesAction(Settings.EMPTY, "testAction", CLUSTER_NAME, threadPool, testNodes[i].clusterService,
+                    testNodes[i].transportService) {
                 @Override
                 protected NodeResponse nodeOperation(NodeRequest request) {
                     logger.info("Action on node {}", node);
@@ -577,7 +584,8 @@ public class TransportTasksActionTests extends TaskManagerTestCase {
         RecordingTaskManagerListener[] listeners = setupListeners(testNodes, "testAction*");
         for (int i = 0; i < testNodes.length; i++) {
             final int node = i;
-            actions[i] = new TestNodesAction(Settings.EMPTY, "testAction", clusterName, threadPool, testNodes[i].clusterService, testNodes[i].transportService) {
+            actions[i] = new TestNodesAction(Settings.EMPTY, "testAction", CLUSTER_NAME, threadPool, testNodes[i].clusterService,
+                    testNodes[i].transportService) {
                 @Override
                 protected NodeResponse nodeOperation(NodeRequest request) {
                     logger.info("Action on node {}", node);
@@ -616,7 +624,8 @@ public class TransportTasksActionTests extends TaskManagerTestCase {
         for (int i = 0; i < testNodes.length; i++) {
             final int node = i;
             // Simulate task action that fails on one of the tasks on one of the nodes
-            tasksActions[i] = new TestTasksAction(Settings.EMPTY, "testTasksAction", clusterName, threadPool, testNodes[i].clusterService, testNodes[i].transportService) {
+            tasksActions[i] = new TestTasksAction(Settings.EMPTY, "testTasksAction", CLUSTER_NAME, threadPool, testNodes[i].clusterService,
+                    testNodes[i].transportService) {
                 @Override
                 protected TestTaskResponse taskOperation(TestTasksRequest request, Task task) {
                     logger.info("Task action on node {}", node);
@@ -673,7 +682,7 @@ public class TransportTasksActionTests extends TaskManagerTestCase {
             final int node = i;
             // Simulate a task action that works on all nodes except nodes listed in filterNodes.
             // We are testing that it works.
-            tasksActions[i] = new TestTasksAction(Settings.EMPTY, "testTasksAction", clusterName, threadPool,
+            tasksActions[i] = new TestTasksAction(Settings.EMPTY, "testTasksAction", CLUSTER_NAME, threadPool,
                 testNodes[i].clusterService, testNodes[i].transportService) {
 
                 @Override