trunk/proposal/sandbox/junit/src/main/org/apache/tools/ant/taskdefs/optional/rjunit/remote/Server.java

/*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2002 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
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 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
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 * 4. The names "The Jakarta Project", "Ant", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
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 * This software consists of voluntary contributions made by many
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 * information on the Apache Software Foundation, please see
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 */
package org.apache.tools.ant.taskdefs.optional.rjunit.remote;

import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * The server that will receive events from a remote client.
 *
 * <i>
 * This code is based on the code from Erich Gamma made for the
 * JUnit plugin for <a href="http://www.eclipse.org">Eclipse</a> and is
 * merged with code originating from Ant 1.4.x.
 * </i>
 *
 * @see TestRunner
 */
public class Server {

    /** the port where the server is listening */
    private int port = -1;

    /** the server socket */
    private ServerSocket server;

    /** the client that is connected to the server */
    private Socket client;

    /** the reader in charge of interpreting messages from the client */
    private Messenger messenger;

    private EventDispatcher dispatcher = new EventDispatcher();

    public Server(int port) {
        this.port = port;
    }

    protected void finalize() throws Exception {
        cancel();
        shutdown();
    }

    /**
     * add a new listener
     * @param listener a instance of a listener.
     */
    public void addListener(TestRunListener listener) {
        dispatcher.addListener(listener);
    }

    /**
     * remove an existing listener
     * @param listener a instance of a listener.
     */
    public void removeListener(TestRunListener listener) {
        dispatcher.removeListener(listener);
    }

    /** return whether there is a client running or not */
    public synchronized boolean isRunning() {
        return client != null && server != null && messenger != null;
    }

    /** start a server to the specified port */
    public void start(boolean loop) throws IOException {
        server = new ServerSocket(port);
        while (server != null) {
            client = server.accept();
            messenger = new Messenger(client.getInputStream(), client.getOutputStream());
            TestRunEvent evt = null;
            try {
                while ( (evt = messenger.read()) != null ) {
                    dispatcher.dispatchEvent(evt);
                }
            } catch (Exception e){
                e.printStackTrace();
                //@fixme this stacktrace might be normal when closing
                // the socket. So decompose the above in distinct steps
            }
            if (!loop){
                break;
            }
        }
    }

    /** cancel the connection to the client */
    public synchronized void cancel() {
        if (isRunning()) {
            TestRunEvent evt = new TestRunEvent(new Integer(-1), TestRunEvent.RUN_STOP);
            try {
                messenger.writeEvent(evt);
            } catch (IOException e){
            }
        }
    }

    /** shutdown the server and any running client */
    public synchronized void shutdown() {
        try {
            if (messenger != null) {
                messenger.close();
                messenger = null;
            }
        } catch (IOException e){
        }
        try {
            if (client != null) {
                client.shutdownInput();
                client.shutdownOutput();
                client.close();
                client = null;
            }
        } catch (IOException e) {
        }
        try {
            if (server != null) {
                server.close();
                server = null;
            }
        } catch (IOException e) {
        }
    }
}