svn merge -c 1179512 from trunk for HADOOP-7695.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23-PB@1230422 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -36,6 +36,9 @@ Release 0.23-PB - Unreleased
 
   BUG FIXES
 
+    HADOOP-7695. RPC.stopProxy can throw unintended exception while logging
+                 error (atm)
+
     HADOOP-7833. Fix findbugs warnings in protobuf generated code.
     (John Lee via suresh)
 

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/RPC.java

@@ -567,7 +567,8 @@ public class RPC {
       }
     } else {
       LOG.error("Could not get invocation handler " + invocationHandler +
-          " for proxy " + proxy + ", or invocation handler is not closeable.");
+          " for proxy class " + (proxy == null ? null : proxy.getClass()) +
+          ", or invocation handler is not closeable.");
     }
   }