Re: Serialization issue with generic Maps
The problem is you cannot use Object as a type argument Regards, Ronald --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups Google Web Toolkit group. To post to this group, send email to Google-Web-Toolkit@googlegroups.com To unsubscribe from this group, send email to google-web-toolkit+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/Google-Web-Toolkit?hl=en -~--~~~~--~~--~--~---
Re: Serialization issue with generic Maps
Object is the super class of EVERY java object, by telling GWT that
you are returning Object, it would force the compiler to generate a
serializer for every serializable object on its classpath! that is
horribly inefficient. you'll want to narrow that type down a bit.
-jason
On Apr 2, 2009, at 8:32 AM, snorbi wrote:
Hello,
We have problems serializing generic Maps in gwt-1.6.2 (both in web
and hosted mode). It seems that type parameters of generic remote
service method parameters are not scanned properly when searching for
potential serializable types.
To reproduce the problem, please see the application snippet below. It
is a minimal GWT application which calls a remote service from its
entry method.
Running the application results in the following exception:
[ERROR] failure
com.google.gwt.user.client.rpc.SerializationException:
gwtsandbox.client.Parameter
at
gwtsandbox.client.Service_TypeSerializer.raiseSerializationException
(Service_TypeSerializer.java:69)
at gwtsandbox.client.Service_TypeSerializer.serialize(Native Method)
at
com
.google
.gwt.user.client.rpc.impl.ClientSerializationStreamWriter.serialize
(ClientSerializationStreamWriter.java:216)
at
com
.google
.gwt
.user.client.rpc.impl.AbstractSerializationStreamWriter.writeObject
(AbstractSerializationStreamWriter.java:129)
at
com
.google
.gwt
.user
.client.rpc.core.java.util.Map_CustomFieldSerializerBase.serialize
(Map_CustomFieldSerializerBase.java:50)
at
com
.google
.gwt
.user
.client.rpc.core.java.util.HashMap_CustomFieldSerializer.serialize
(HashMap_CustomFieldSerializer.java:36)
at gwtsandbox.client.Service_TypeSerializer.serialize(Native Method)
at
com
.google
.gwt.user.client.rpc.impl.ClientSerializationStreamWriter.serialize
(ClientSerializationStreamWriter.java:216)
at
com
.google
.gwt
.user.client.rpc.impl.AbstractSerializationStreamWriter.writeObject
(AbstractSerializationStreamWriter.java:129)
at gwtsandbox.client.Service_Proxy.serviceMethod(Service_Proxy.java:
31)
at gwtsandbox.client.Application.onModuleLoad(Application.java:20)
Uncommenting the lines marked with // FIX, it works as expected.
I think it is a bug, what do you think?
Thanks for your help!
Regards:
Norbi
Application.gwt.xml
---
module
inherits name='com.google.gwt.user.User' /
entry-point class='gwtsandbox.client.Application' /
source path=client /
/module
Application.java
package gwtsandbox.client;
import java.util.HashMap;
import java.util.Map;
import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.core.client.GWT;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.rpc.ServiceDefTarget;
public class Application implements EntryPoint {
public void onModuleLoad() {
MapString, Object map = new HashMapString, Object();
map.put(key, new Parameter(5));
ServiceAsync serviceProxy = GWT.create(Service.class);
((ServiceDefTarget) serviceProxy).setServiceEntryPoint
(GWT.getHostPageBaseURL() + gwt/rpc/
+ Service.class.getName());
serviceProxy.serviceMethod(map, new AsyncCallbackVoid() {
@Override
public void onFailure(Throwable caught) {
Window.alert(caught.toString());
System.out.println(caught);
}
@Override
public void onSuccess(Void result) {
Window.alert(success);
}
});
}
}
Parameter.java
--
package gwtsandbox.client;
import java.io.Serializable;
import com.google.gwt.user.client.rpc.IsSerializable;
public class Parameter implements Serializable, IsSerializable {
private static final long serialVersionUID = 1L;
private int value;
public Parameter() {
}
public Parameter(int value) {
setValue(value);
}
public int getValue() {
return value;
}
public void setValue(int value) {
this.value = value;
}
}
Service.java
package gwtsandbox.client;
import java.util.Map;
import com.google.gwt.user.client.rpc.RemoteService;
public interface Service extends RemoteService {
void serviceMethod(MapString, Object map);
// FIX void serviceMethod(Parameter parameter);
}
ServiceAsync.java
-
package gwtsandbox.client;
import java.util.Map;
import com.google.gwt.user.client.rpc.AsyncCallback;
public interface ServiceAsync {
void serviceMethod(MapString, Object map, AsyncCallbackVoid
callback);
// FIX void serviceMethod(Parameter parameter, AsyncCallbackVoid
callback);
}
ServiceServlet.java
---
package gwtsandbox.server;
import java.util.Map;
import gwtsandbox.client.Parameter;
import
Re: Serialization issue with generic Maps
Here's a similar thread with possible workarounds:
http://groups.google.com/group/Google-Web-Toolkit/browse_thread/thread/a3081e050d5b719a#
On Apr 2, 4:32 pm, snorbi sandor.norb...@erinors.com wrote:
Hello,
We have problems serializing generic Maps in gwt-1.6.2 (both in web
and hosted mode). It seems that type parameters of generic remote
service method parameters are not scanned properly when searching for
potential serializable types.
To reproduce the problem, please see the application snippet below. It
is a minimal GWT application which calls a remote service from its
entry method.
Running the application results in the following exception:
[ERROR] failure
com.google.gwt.user.client.rpc.SerializationException:
gwtsandbox.client.Parameter
at
gwtsandbox.client.Service_TypeSerializer.raiseSerializationException
(Service_TypeSerializer.java:69)
at gwtsandbox.client.Service_TypeSerializer.serialize(Native Method)
at
com.google.gwt.user.client.rpc.impl.ClientSerializationStreamWriter.serialize
(ClientSerializationStreamWriter.java:216)
at
com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamWriter.writeObject
(AbstractSerializationStreamWriter.java:129)
at
com.google.gwt.user.client.rpc.core.java.util.Map_CustomFieldSerializerBase.serialize
(Map_CustomFieldSerializerBase.java:50)
at
com.google.gwt.user.client.rpc.core.java.util.HashMap_CustomFieldSerializer.serialize
(HashMap_CustomFieldSerializer.java:36)
at gwtsandbox.client.Service_TypeSerializer.serialize(Native Method)
at
com.google.gwt.user.client.rpc.impl.ClientSerializationStreamWriter.serialize
(ClientSerializationStreamWriter.java:216)
at
com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamWriter.writeObject
(AbstractSerializationStreamWriter.java:129)
at gwtsandbox.client.Service_Proxy.serviceMethod(Service_Proxy.java:
31)
at gwtsandbox.client.Application.onModuleLoad(Application.java:20)
Uncommenting the lines marked with // FIX, it works as expected.
I think it is a bug, what do you think?
Thanks for your help!
Regards:
Norbi
Application.gwt.xml
---
module
inherits name='com.google.gwt.user.User' /
entry-point class='gwtsandbox.client.Application' /
source path=client /
/module
Application.java
package gwtsandbox.client;
import java.util.HashMap;
import java.util.Map;
import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.core.client.GWT;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.rpc.ServiceDefTarget;
public class Application implements EntryPoint {
public void onModuleLoad() {
MapString, Object map = new HashMapString, Object();
map.put(key, new Parameter(5));
ServiceAsync serviceProxy = GWT.create(Service.class);
((ServiceDefTarget) serviceProxy).setServiceEntryPoint
(GWT.getHostPageBaseURL() + gwt/rpc/
+ Service.class.getName());
serviceProxy.serviceMethod(map, new AsyncCallbackVoid() {
@Override
public void onFailure(Throwable caught) {
Window.alert(caught.toString());
System.out.println(caught);
}
@Override
public void onSuccess(Void result) {
Window.alert(success);
}
});
}
}
Parameter.java
--
package gwtsandbox.client;
import java.io.Serializable;
import com.google.gwt.user.client.rpc.IsSerializable;
public class Parameter implements Serializable, IsSerializable {
private static final long serialVersionUID = 1L;
private int value;
public Parameter() {
}
public Parameter(int value) {
setValue(value);
}
public int getValue() {
return value;
}
public void setValue(int value) {
this.value = value;
}
}
Service.java
package gwtsandbox.client;
import java.util.Map;
import com.google.gwt.user.client.rpc.RemoteService;
public interface Service extends RemoteService {
void serviceMethod(MapString, Object map);
// FIX void serviceMethod(Parameter parameter);
}
ServiceAsync.java
-
package gwtsandbox.client;
import java.util.Map;
import com.google.gwt.user.client.rpc.AsyncCallback;
public interface ServiceAsync {
void serviceMethod(MapString, Object map, AsyncCallbackVoid
callback);
// FIX void serviceMethod(Parameter parameter, AsyncCallbackVoid
callback);
}
ServiceServlet.java
---
package gwtsandbox.server;
import java.util.Map;
import gwtsandbox.client.Parameter;
import gwtsandbox.client.Service;
import com.google.gwt.user.server.rpc.RemoteServiceServlet;
public class ServiceServlet extends
