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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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
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package org.apache.cayenne.remote.service;
import java.io.Serializable;
import org.apache.cayenne.CayenneRuntimeException;
import org.apache.cayenne.DataChannel;
import org.apache.cayenne.event.EventBridge;
import org.apache.cayenne.remote.BaseConnection;
import org.apache.cayenne.remote.ClientMessage;
import org.apache.cayenne.remote.hessian.service.HessianUtil;
import org.apache.cayenne.util.Util;
/**
* A ClientConnection that connects to a DataChannel. Used as an emulator of a remote
* service. Emulation includes serialization/deserialization of objects.
*
* @since 1.2
* @author Andrus Adamchik
*/
public class LocalConnection extends BaseConnection {
public static final int NO_SERIALIZATION = 0;
public static final int JAVA_SERIALIZATION = 1;
public static final int HESSIAN_SERIALIZATION = 2;
protected DataChannel channel;
protected int serializationPolicy;
/**
* Creates LocalConnector with specified handler and no serialization.
*/
public LocalConnection(DataChannel handler) {
this(handler, NO_SERIALIZATION);
}
/**
* Creates a LocalConnector with specified handler and serialization policy. Valid
* policies are defined as final static int field in this class.
*/
public LocalConnection(DataChannel handler, int serializationPolicy) {
this.channel = handler;
// convert invalid policy to NO_SER..
this.serializationPolicy = serializationPolicy == JAVA_SERIALIZATION
|| serializationPolicy == HESSIAN_SERIALIZATION
? serializationPolicy
: NO_SERIALIZATION;
}
public boolean isSerializingMessages() {
return serializationPolicy == JAVA_SERIALIZATION
|| serializationPolicy == HESSIAN_SERIALIZATION;
}
/**
* Returns wrapped DataChannel.
*/
public DataChannel getChannel() {
return channel;
}
/**
* Returns null.
*/
public EventBridge getServerEventBridge() {
return null;
}
/**
* Does nothing.
*/
@Override
protected void beforeSendMessage(ClientMessage message) {
// noop
}
/**
* Dispatches a message to an internal handler.
*/
@Override
protected Object doSendMessage(ClientMessage message) throws CayenneRuntimeException {
ClientMessage processedMessage;
try {
switch (serializationPolicy) {
case HESSIAN_SERIALIZATION:
processedMessage = (ClientMessage) HessianUtil
.cloneViaClientServerSerialization(message, channel
.getEntityResolver());
break;
case JAVA_SERIALIZATION:
processedMessage = (ClientMessage) Util
.cloneViaSerialization(message);
break;
default:
processedMessage = message;
}
}
catch (Exception ex) {
throw new CayenneRuntimeException("Error serializing message", ex);
}
Serializable result = (Serializable) DispatchHelper.dispatch(
channel,
processedMessage);
try {
switch (serializationPolicy) {
case HESSIAN_SERIALIZATION:
return HessianUtil.cloneViaServerClientSerialization(result, channel
.getEntityResolver());
case JAVA_SERIALIZATION:
return Util.cloneViaSerialization(result);
default:
return result;
}
}
catch (Exception ex) {
throw new CayenneRuntimeException("Error deserializing result", ex);
}
}
}