[FIXED JENKINS-9050] Improved the error diagnostics when a remote method call fails to deserialize.

changelog.html

@@ -90,6 +90,9 @@ Upcoming changes</a>
   <li class=rfe>
     Added a new axis type to the matrix project that lets you use boolean expressions
     (<a href="https://github.com/jenkinsci/jenkins/pull/66">pull request #66</a>)
+  <li class=rfe>
+    Improved the error diagnostics when a remote method call fails to deserialize.
+    (<a href="http://issues.jenkins-ci.org/browse/JENKINS-9050">issue 9050</a>)
 </ul>
 </div><!--=TRUNK-END=-->
 

remoting/src/main/java/hudson/remoting/UserRequest.java

@@ -98,6 +98,10 @@ final class UserRequest<RSP,EXC extends Throwable> extends Request<UserResponse<
                     o = deserialize(channel,request,cl);
                 } catch (ClassNotFoundException e) {
                     throw new ClassNotFoundException("Failed to deserialize the Callable object. Perhaps you needed to implement DelegatingCallable?",e);
+                } catch (RuntimeException e) {
+                    // if the error is during deserialization, throw it in one of the types Channel.call will
+                    // capture its call site stack trace. See 
+                    throw new Error("Failed to deserialize the Callable object.",e);
                 }
 
                 Callable<RSP,EXC> callable = (Callable<RSP,EXC>)o;

remoting/src/test/java/hudson/remoting/ChannelTest.java

 package hudson.remoting;
 
+import org.jvnet.hudson.test.Bug;
+
+import java.io.IOException;
+import java.io.ObjectInputStream;
+
 /**
  * @author Kohsuke Kawaguchi
  */
@@ -7,4 +12,26 @@ public class ChannelTest extends RmiTestBase {
     public void testCapability() {
         assertTrue(channel.remoteCapability.supportsMultiClassLoaderRPC());
     }
+
+    @Bug(9050)
+    public void testFailureInDeserialization() throws Exception {
+        try {
+            channel.call(new CallableImpl());
+            fail();
+        } catch (IOException e) {
+            e.printStackTrace();
+            assertEquals("foobar",e.getCause().getCause().getMessage());
+            assertTrue(e.getCause().getCause() instanceof ClassCastException);
+        }
+    }
+
+    private static class CallableImpl implements Callable<Object,IOException> {
+        public Object call() throws IOException {
+            return null;
+        }
+
+        private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException {
+            throw new ClassCastException("foobar");
+        }
+    }
 }