001// Copyright 2005 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.hivemind.internal.ser;
016
017import java.io.Externalizable;
018import java.io.IOException;
019import java.io.ObjectInput;
020import java.io.ObjectOutput;
021
022import org.apache.hivemind.util.Defense;
023
024/**
025 * Instance used to replace actual service (proxies) during serialization. Note that this represents
026 * a back-door into HiveMind's {@link org.apache.hivemind.internal.RegistryInfrastructure}, which
027 * is less than ideal, and should not be used by end-user code!
028 * 
029 * @author Howard M. Lewis Ship
030 * @since 1.1
031 */
032public class ServiceToken implements Externalizable
033{
034    private static final long serialVersionUID = 1L;
035    private String _serviceId;
036
037    // Needed for Externalizable.
038
039    public ServiceToken()
040    {
041    }
042
043    public ServiceToken(String serviceId)
044    {
045        Defense.notNull(serviceId, "serviceId");
046
047        _serviceId = serviceId;
048    }
049
050    public String getServiceId()
051    {
052        return _serviceId;
053    }
054
055    public void writeExternal(ObjectOutput out) throws IOException
056    {
057        out.writeUTF(_serviceId);
058    }
059
060    public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException
061    {
062        _serviceId = in.readUTF();
063    }
064
065    Object readResolve()
066    {
067        return ServiceSerializationHelper.getServiceSerializationSupport()
068                .getServiceFromToken(this);
069    }
070}