RPC Error after GWT 2.3 upgrade

Question

After upgrading to GWT 2.3 some of my RPC services no longer work and fail with "The response could not be deserialized". It seems to happen to services that are returning objects that are use Date objects that are annotated with @Temporal(TemporalType.TIMESTAMP). I use Gilead 1.3.2 and Hibernate 3.6 and I had no issues with GWT 2.2. Any idea what could be going on, or how to start debugging?

Here's the stack trace:

com.google.gwt.user.client.rpc.IncompatibleRemoteServiceException: The response could not be deserialized
  at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter.onResponseReceived(RequestCallbackAdapter.java:221)
  at com.google.gwt.http.client.Request.fireOnResponseReceived(Request.java: 287)
  at com.google.gwt.http.client.RequestBuilder$1.onReadyStateChange(RequestBuilder.java:395)
  at sun.reflect.GeneratedMethodAccessor33.invoke(Unknown Source)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImp l.java:25)
  at java.lang.reflect.Method.invoke(Method.java:597) 
  at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
  at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
  at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:167)
  at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessagesWhileWaitingForReturn(BrowserChannelServer.java:326)
  at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:207)
  at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:132)
  at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:561)
  at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:269)
  at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91)
  at com.google.gwt.core.client.impl.Impl.apply(Impl.java)
  at com.google.gwt.core.client.impl.Impl.apply(Impl.java)
  at com.google.gwt.core.client.impl.Impl.entry0(Impl.java:214)
  at sun.reflect.GeneratedMethodAccessor27.invoke(Unknown Source)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
  at java.lang.reflect.Method.invoke(Method.java:597)
  at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
  at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
  at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:167)
  at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:281)
  at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:531)
  at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:352)
  at java.lang.Thread.run(Thread.java:680)
Caused by: com.google.gwt.user.client.rpc.SerializationException: java.sql.Timestamp/1769758459
Caused by: com.google.gwt.user.client.rpc.SerializationException: java.sql.Timestamp/1769758459
  at com.google.gwt.user.client.rpc.impl.SerializerBase.getTypeHandler(SerializerBase.java:153)
  at com.google.gwt.user.client.rpc.impl.SerializerBase.instantiate(SerializerBase.java:114)
  at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:111)
  at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119)
  at com.lensoo.shared.entity.Course_FieldSerializer.deserialize(Course_FieldSerializer.java:320)
  at com.lensoo.shared.entity.Course_FieldSerializer.deserial(Course_FieldSerializer.java:405)
  at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95)
  at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113)
  at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119)
  at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter$ResponseReader$8.read(RequestCallbackAdapter.java:106) 
  at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter.onResponseReceived(RequestCallbackAdapter.java:214)
  ... 26 more 
  ... 26 more

Nora

Did you also upgrade to GWT 2.3 on the service side? Is there a stack trace from the server? – Britton

May be the objects which you are using are not implementing interface serializable, that's what I think. – Sidoon

Is this problem fixed in more recent GWT releases? (I'm trying to upgrade to 2.5.0-rc1) Or do we need to apply a fix for certain? (Gilead 1.3.2) – Eakin

Answer 1

I have very similar problem - Gilead 1.3.1, Hibernate. Exception is also complaining on Timestamp field.

Here's something that I found at Gilead's website:

"Timestamp_FieldSerializer that ships with Gilead conflicts with one that was apparently introduced in GWT 2.2 or 2.3"

http://sourceforge.net/tracker/index.php?func=detail&aid=3285026&group_id=239931&atid=1111398

End of "Details" section suggests the easy fix, however, I haven't tried that yet.

Housum

Thanks for the help. For the curious, remove the package com.google.gwt.user.client.rpc.core.java.sql from gilead4gwt.jar – Nora

Answer 2

If you don't want to touch JARs - when you use Gilead 1.3.2 as Maven dependecy, there is a better solution I've found today.

Conflicting Gilead serializers must be shadowed by these from GWT 2.3, but as both JARs are on the same level and positioning inherit in gwt.xml doesn't help these must be reimplemented in your project structure. "New" serializers will take precedence both on server and compiled client. Finally you get working GWT 2.3 and Gilead 1.3.2.

In steps:

1. Create package com.google.gwt.user.client.rpc.core.java.sql in your project.
2. Using Eclipse open gwt-servlet-2.3.jar and find above package with three files Date_CustomFieldSerializer.class, Time_CustomFieldSerializer.class and Timestamp_CustomFieldSerializer.class. You should see source if Maven downloaded it.
3. Recreate these source files in your project.

I suppose Gilead team should remove serializers in next release then you delete these from your project as well.

Cuirbouilli

Answer 3

Simply you can search on [project_path]/war/WEB-INF/lib for the library json.jar and add it to the build path (I'm using Eclipse).

Blubbery

Answer 4

It's very simple. You just have to deleting the com.google.* package from the gilead4gwt-1.3.2.1839.jar.

In fact it does solve this issue.

Bordie