/*
* Copyright 2008 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.google.gwt.rpc.client.impl;
import com.google.gwt.http.client.Request;
import com.google.gwt.http.client.RequestCallback;
import com.google.gwt.http.client.Response;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.rpc.IncompatibleRemoteServiceException;
import com.google.gwt.user.client.rpc.InvocationException;
import com.google.gwt.user.client.rpc.SerializationException;
import com.google.gwt.user.client.rpc.SerializationStreamFactory;
import com.google.gwt.user.client.rpc.StatusCodeException;
import com.google.gwt.user.client.rpc.impl.RemoteServiceProxy;
/**
* Adapter from a {@link RequestCallback} interface to an {@link AsyncCallback}
* interface.
*
* For internal use only.
*
* @param <T> the type parameter for the {@link AsyncCallback}
*/
public class RpcCallbackAdapter<T> implements RequestCallback {
/**
* {@link AsyncCallback} to notify or success or failure.
*/
private final AsyncCallback<T> callback;
/**
* Used for stats recording.
*/
private final String methodName;
/**
* Used for stats recording.
*/
private final int requestId;
private final SerializationStreamFactory streamFactory;
public RpcCallbackAdapter(SerializationStreamFactory streamFactory,
String methodName, int requestId, AsyncCallback<T> callback) {
assert (streamFactory != null);
assert (callback != null);
this.streamFactory = streamFactory;
this.callback = callback;
this.methodName = methodName;
this.requestId = requestId;
}
public void onError(Request request, Throwable exception) {
callback.onFailure(exception);
}
@SuppressWarnings(value = {"unchecked", "unused"})
public void onResponseReceived(Request request, Response response) {
T result = null;
Throwable caught = null;
try {
String encodedResponse = response.getText();
int statusCode = response.getStatusCode();
boolean toss = RemoteServiceProxy.isStatsAvailable()
&& RemoteServiceProxy.stats(RemoteServiceProxy.bytesStat(methodName,
requestId, encodedResponse.length(), "responseReceived"));
if (statusCode != Response.SC_OK) {
caught = new StatusCodeException(statusCode, encodedResponse);
} else if (encodedResponse == null) {
// This can happen if the XHR is interrupted by the server dying
caught = new InvocationException("No response payload");
} else {
result = (T) streamFactory.createStreamReader(encodedResponse).readObject();
}
} catch (RemoteException e) {
caught = e.getCause();
} catch (SerializationException e) {
caught = new IncompatibleRemoteServiceException(
"The response could not be deserialized", e);
} catch (Throwable e) {
caught = e;
} finally {
boolean toss = RemoteServiceProxy.isStatsAvailable()
&& RemoteServiceProxy.stats(RemoteServiceProxy.timeStat(methodName,
requestId, "responseDeserialized"));
}
try {
if (caught == null) {
callback.onSuccess(result);
} else {
callback.onFailure(caught);
}
} finally {
boolean toss = RemoteServiceProxy.isStatsAvailable()
&& RemoteServiceProxy.stats(RemoteServiceProxy.timeStat(methodName,
requestId, "end"));
}
}
}