server.java

Java写的含有一个jdbc驱动的小型数据库数据库引擎

/*
 * Server.java
 *
 * Copyright (c) 2001, The HSQL Development Group
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * 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.
 *
 *
 * Neither the name of the HSQL Development Group nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This package is based on HypersonicSQL, originally developed by Thomas Mueller.
 *
 */

/**
 * <font color="#009900">
 * Server acts as a database server and is one way of using
 * the client / server mode of HSQL Database Engine. This server
 * can only process database queries.
 * An applet will need only the JDBC classes to access the database.
 *
 * The Server can be configured with the file 'Server.properties'.
 * This is an example of the file:
 * <pre>
 * port=9001
 * database=test
 * silent=true
 * </font>
 */
package org.hsqldb;

import java.sql.*;
import java.net.*;
import java.io.*;
import java.util.*;

/**
 * Class declaration
 *
 *
 * @version 1.0.0.1
 */
public class Server {
    boolean  mSilent;
    Database mDatabase;

    /**
     * Method declaration
     *
     *
     * @param arg
     */
    public static void main(String arg[]) {
	Server server = new Server();

	server.run(arg);
    }

    /**
     * Method declaration
     *
     *
     * @param arg
     */
    private void run(String arg[]) {
	ServerSocket socket = null;

	try {
	    Properties prop = new Properties();

	    // load parameters from properties file
	    File       f = new File("Server.properties");

	    if (f.exists()) {
		FileInputStream fi = new FileInputStream(f);

		prop.load(fi);
		fi.close();
	    }

	    // overwrite parameters with command line parameters
	    for (int i = 0; i < arg.length; i++) {
		String p = arg[i];

		if (p.equals("-?")) {
		    printHelp();
		}

		if (p.charAt(0) == '-') {
		    prop.put(p.substring(1), arg[i + 1]);

		    i++;
		}
	    }

	    int port = jdbcConnection.DEFAULT_HSQL_PORT;

	    port = Integer.parseInt(prop.getProperty("port", "" + port));

	    String database = prop.getProperty("database", "test");

	    mSilent = prop.getProperty("silent",
				       "true").equalsIgnoreCase("true");

	    if (prop.getProperty("trace", "false").equalsIgnoreCase("true")) {
		DriverManager.setLogStream(System.out);
	    }

	    socket = new ServerSocket(port);

	    trace("port    =" + port);
	    trace("database=" + database);
	    trace("silent  =" + mSilent);

	    mDatabase = new Database(database);

	    System.out.println("Server " + jdbcDriver.VERSION
			       + " is running");
	    System.out.println("Press [Ctrl]+[C] to abort");
	} catch (Exception e) {
	    traceError("Server.run/init: " + e);
	    e.printStackTrace();

	    return;
	}

	try {
	    while (true) {
		Socket		 s = socket.accept();
		ServerConnection c = new ServerConnection(s, this);

		c.start();
	    }
	} catch (IOException e) {
	    traceError("Server.run/loop: " + e.getMessage());
	    e.printStackTrace();
	}
    }

    /**
     * Method declaration
     *
     */
    void printHelp() {
	System.out.println("Usage: java Server [-options]\n"
			   + "where options include:\n"
			   + "    -port <nr>            port where the server is listening\n"
			   + "    -database <name>      name of the database\n"
			   + "    -silent <true/false>  false means display all queries\n"
			   + "    -trace <true/false>   display print JDBC trace messages\n"
			   + "The command line arguments override the values in the properties file.");
	System.exit(0);
    }

    /**
     * Method declaration
     *
     *
     * @param s
     */
    void trace(String s) {
	if (!mSilent) {
	    System.out.println(s);
	}
    }

    /**
     * Method declaration
     *
     *
     * @param s
     */
    void traceError(String s) {
	System.out.println(s);
    }

}