SerializationPolicy error when performing RPC from within GWT application

java serialization gwt rpc gwt-rpc
Tyson picture Tyson · Nov 17, 2010 · Viewed 20.5k times · Source

I'm getting the following exception:

com.google.gwt.user.client.rpc.SerializationException: Type 'java.lang.Long' was not included in the set of types which can be serialized by this SerializationPolicy or its Class object could not be loaded. For security purposes, this type will not be serialized

using GWT 2.1 and the built in Jetty server. According to the docs, this type is definitely serializable... How can I include it in the SerializationPolicy?

Answer

Krzysztof Uroda picture Krzysztof Uroda · Sep 11, 2011

Here's the link that should resolve problem: http://developerlife.com/tutorials/?p=131

A user defined class is serializable if:

  1. the class is assignable to IsSerializable or java.io.Serializable, either because it implements one of these interfaces, or because it is derived from a superclass that implements one of these interfaces.
  2. all the class’s non-final, non-transient instance fields are serializable
  3. the class has a public default (zero argument) constructor

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