diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index 2cb31f83ee0..c075aacbeec 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -1841,9 +1841,11 @@ Release 0.23.0 - Unreleased
     MAPREDUCE-3185. RM Web UI does not sort the columns in some cases.
     (Jonathan Eagles via mahadev)
 
-   MAPREDUCE-3292. In secure mode job submission fails with Provider 
-   org.apache.hadoop.mapreduce.security.token.JobTokenIndentifier$Renewer 
-   not found. (mahadev)
+    MAPREDUCE-3292. In secure mode job submission fails with Provider 
+    org.apache.hadoop.mapreduce.security.token.JobTokenIndentifier$Renewer 
+    not found. (mahadev)
+
+    MAPREDUCE-3296. Fixed the remaining nine FindBugs warnings. (vinodkv)
 
 Release 0.22.0 - Unreleased
 
diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/JobEndNotifier.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/JobEndNotifier.java
index 497edcb5b11..f22b9b7ba02 100644
--- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/JobEndNotifier.java
+++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/JobEndNotifier.java
@@ -44,8 +44,8 @@
  * </p>
  */
 public class JobEndNotifier implements Configurable {
-  final String JOB_ID = "$jobId";
-  final String JOB_STATUS = "$jobStatus";
+  private static final String JOB_ID = "$jobId";
+  private static final String JOB_STATUS = "$jobStatus";
 
   private Configuration conf;
   protected String userUrl;
diff --git a/hadoop-mapreduce-project/hadoop-yarn/dev-support/findbugs-exclude.xml b/hadoop-mapreduce-project/hadoop-yarn/dev-support/findbugs-exclude.xml
index eac86c37dea..0efcb3d2ebf 100644
--- a/hadoop-mapreduce-project/hadoop-yarn/dev-support/findbugs-exclude.xml
+++ b/hadoop-mapreduce-project/hadoop-yarn/dev-support/findbugs-exclude.xml
@@ -171,6 +171,10 @@
     <Class name="org.apache.hadoop.yarn.webapp.WebApps$Builder" />
     <Bug pattern="DM_EXIT" />
   </Match>
+  <Match>
+    <Class name="org.apache.hadoop.yarn.server.resourcemanager.security.DelegationTokenRenewer$DelegationTokenCancelThread" />
+    <Bug pattern="DM_EXIT" />
+  </Match>
   <!-- AsyncDispatcher will kill the process if there is an error dispatching -->
   <Match>
     <Class name="org.apache.hadoop.yarn.event.AsyncDispatcher" />
@@ -185,6 +189,17 @@
     <Bug pattern="DE_MIGHT_IGNORE" />
   </Match>
 
+  <!-- Ignore EI_EXPOSE_REP in PolicyProviders -->
+  <Match>
+    <Class name="org.apache.hadoop.yarn.server.resourcemanager.security.authorize.RMPolicyProvider" />
+    <Bug pattern="EI_EXPOSE_REP" />
+  </Match>
+  <Match>
+    <Class name="org.apache.hadoop.yarn.server.nodemanager.security.authorize.NMPolicyProvider" />
+    <Bug pattern="EI_EXPOSE_REP" />
+  </Match>
+
+
   <!-- Ignore EI_EXPOSE_REP2 in Log services -->
   <Match>
     <Class name="org.apache.hadoop.yarn.server.nodemanager.containermanager.logaggregation.AggregatedLogFormat$LogValue" />
diff --git a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/webapp/WebApps.java b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/webapp/WebApps.java
index 42e4ce4d7a9..22387f067d3 100644
--- a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/webapp/WebApps.java
+++ b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/webapp/WebApps.java
@@ -20,6 +20,7 @@
 
 import static com.google.common.base.Preconditions.checkNotNull;
 
+import java.io.IOException;
 import java.net.ConnectException;
 import java.net.URL;
 import java.util.HashMap;
@@ -191,7 +192,9 @@ public void setup() {
         webapp.setHttpServer(server);
         server.start();
         LOG.info("Web app /"+ name +" started at "+ server.getPort());
-      } catch (Exception e) {
+      } catch (ClassNotFoundException e) {
+        throw new WebAppException("Error starting http server", e);
+      } catch (IOException e) {
         throw new WebAppException("Error starting http server", e);
       }
       Injector injector = Guice.createInjector(webapp, new AbstractModule() {
diff --git a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/ProxyUriUtils.java b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/ProxyUriUtils.java
index 20fb8f0c74d..e9bc0c81f8e 100644
--- a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/ProxyUriUtils.java
+++ b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/ProxyUriUtils.java
@@ -92,7 +92,7 @@ public static String getPathAndQuery(ApplicationId id, String path,
     newp.append(getPath(id, path));
     boolean first = appendQuery(newp, query, true);
     if(approved) {
-      first = appendQuery(newp, PROXY_APPROVAL_PARAM+"=true", first);
+      appendQuery(newp, PROXY_APPROVAL_PARAM+"=true", first);
     }
     return newp.toString();
   }
diff --git a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/amfilter/AmIpFilter.java b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/amfilter/AmIpFilter.java
index 9705b49ccd3..d1cae5cc1eb 100644
--- a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/amfilter/AmIpFilter.java
+++ b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/amfilter/AmIpFilter.java
@@ -59,8 +59,8 @@ public void init(FilterConfig conf) throws ServletException {
   
   private Set<String> getProxyAddresses() throws ServletException {
     long now = System.currentTimeMillis();
-    if(proxyAddresses == null || (lastUpdate + updateInterval) >= now) {
-      synchronized(this) {
+    synchronized(this) {
+      if(proxyAddresses == null || (lastUpdate + updateInterval) >= now) {
         try {
           proxyAddresses = new HashSet<String>();
           for(InetAddress add : InetAddress.getAllByName(proxyHost)) {
@@ -71,8 +71,8 @@ private Set<String> getProxyAddresses() throws ServletException {
           throw new ServletException("Could not locate "+proxyHost, e);
         }
       }
+      return proxyAddresses;
     }
-    return proxyAddresses;
   }
 
   @Override