HADOOP-6475. Adding some javadoc to Server.RpcMetrics, UGI. Contributed by Jitendra Pandey and borya.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@979919 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -86,6 +86,9 @@ Trunk (unreleased changes)
     HADOOP-6877. Common part of HDFS-1178 (NameNode servlets should communicate
     with NameNode directrly). (Kan Zhang via jghoman)
     
+    HADOOP-6475. Adding some javadoc to Server.RpcMetrics, UGI. 
+    (Jitendra Pandey and borya via jghoman)
+
   OPTIMIZATIONS
 
   BUG FIXES

src/java/org/apache/hadoop/ipc/Server.java

@@ -231,7 +231,10 @@ public static void bind(ServerSocket socket, InetSocketAddress address,
     }
   }
   
-  /*Returns a handle to the rpcMetrics (required in tests)*/
+  /**
+   * Returns a handle to the rpcMetrics (required in tests)
+   * @return rpc metrics
+   */
   public RpcMetrics getRpcMetrics() {
     return rpcMetrics;
   }

src/java/org/apache/hadoop/ipc/metrics/RpcMetrics.java

@@ -76,26 +76,57 @@ public RpcMetrics(final String hostName, final String port,
    *  -they can also be read directly - e.g. JMX does this.
    */
 
+  /**
+   * metrics - number of bytes received
+   */
   public final MetricsTimeVaryingLong receivedBytes = 
          new MetricsTimeVaryingLong("ReceivedBytes", registry);
+  /**
+   * metrics - number of bytes sent
+   */
   public final MetricsTimeVaryingLong sentBytes = 
          new MetricsTimeVaryingLong("SentBytes", registry);
+  /**
+   * metrics - rpc queue time
+   */
   public final MetricsTimeVaryingRate rpcQueueTime =
           new MetricsTimeVaryingRate("RpcQueueTime", registry);
-  public MetricsTimeVaryingRate rpcProcessingTime =
+  /**
+   * metrics - rpc processing time
+   */
+  public final MetricsTimeVaryingRate rpcProcessingTime =
           new MetricsTimeVaryingRate("RpcProcessingTime", registry);
+  /**
+   * metrics - number of open connections
+   */
   public final MetricsIntValue numOpenConnections = 
           new MetricsIntValue("NumOpenConnections", registry);
+  /**
+   * metrics - length of the queue
+   */
   public final MetricsIntValue callQueueLen = 
           new MetricsIntValue("callQueueLen", registry);
+  /**
+   * metrics - number of failed authentications
+   */
   public final MetricsTimeVaryingInt authenticationFailures = 
           new MetricsTimeVaryingInt("rpcAuthenticationFailures", registry);
+  /**
+   * metrics - number of successful authentications
+   */
   public final MetricsTimeVaryingInt authenticationSuccesses = 
           new MetricsTimeVaryingInt("rpcAuthenticationSuccesses", registry);
+  /**
+   * metrics - number of failed authorizations
+   */
   public final MetricsTimeVaryingInt authorizationFailures = 
           new MetricsTimeVaryingInt("rpcAuthorizationFailures", registry);
+  /**
+   * metrics - number of successful authorizations
+   */
   public final MetricsTimeVaryingInt authorizationSuccesses = 
          new MetricsTimeVaryingInt("rpcAuthorizationSuccesses", registry);
+  
   /**
    * Push the metrics to the monitoring subsystem on doUpdate() call.
    */
@@ -113,6 +144,9 @@ public void doUpdates(final MetricsContext context) {
     metricsRecord.update();
   }
 
+  /**
+   * shutdown the metrics
+   */
   public void shutdown() {
     if (rpcMBean != null) 
       rpcMBean.shutdown();

src/java/org/apache/hadoop/security/UserGroupInformation.java

@@ -556,6 +556,9 @@ public static UserGroupInformation createRemoteUser(String user) {
     return new UserGroupInformation(subject);
   }
 
+  /**
+   * existing types of authentications' methods
+   */
   @InterfaceStability.Evolving
   public static enum AuthenticationMethod {
     SIMPLE,
@@ -566,7 +569,8 @@ public static enum AuthenticationMethod {
     PROXY;
   }
 
-  /* Create a proxy user using username of the effective user and the ugi of the
+  /**
+   * Create a proxy user using username of the effective user and the ugi of the
    * real user.
    *
    * @param effective
@@ -587,6 +591,10 @@ public static UserGroupInformation createProxyUser(String user,
     return new UserGroupInformation(subject);
   }
 
+  /**
+   * get RealUser (vs. EffectiveUser)
+   * @return realUser running over proxy user
+   */
   public UserGroupInformation getRealUser() {
     for (RealUser p: subject.getPrincipals(RealUser.class)) {
       return p.getRealUser();