18.txt

电子工业出版社出版的《java2应用开发指南》配套光盘源代码

例程18-1
//TimeOutDemo.java
import java.net.*;

class TimeOutDemo
{
    public static void main(String[] args) 
{
        SocketImpl impl = new MyPlainSocketImpl();
        Try
{
        //设置超时时长为1秒
        impl.setOption(SocketOptions.SO_TIMEOUT, new Integer(1000));
        int timeout =
((Integer)impl.getOption(SocketOptions.SO_TIMEOUT)).intValue();
        }
catch (java.io.IOException e)
{
System.out.println(e);
}
    }
}



例程18-2
//SetSendBufferDemo.java
import java.net.*;

class SetSendBufferDemo 
{
    public static void main(String[] args)
{
        SocketImpl impl = new MyPlainSocketImpl();
        Try
{
        	// 设置发送缓冲区为1K字节
        	impl.setOption(SocketOptions.SO_SNDBUF, new Integer(1024));
        	// 读取缓冲区所用的大小
        	int size =
((Integer)(impl.getOption(SocketOptions.SO_SNDBUF))).intValue();
        }
catch (java.io.IOException e)
{
System.out.println(e);
}
    }
}



例程18-3
//EchoChar.java
import java.io.*;
import java.net.*;
public class EchoChar 
{
    public static void main(String[] args) throws IOException 
{
		//申请套接字资源
        Socket echoSocket = null;
		//申请数据输入、输出流
        DataOutputStream out = null;
        DataInputStream in = null;
        try
{
	//创建套接字
            echoSocket = new Socket(10.65.111.101, 7);
			//获取数据输出流
            out = new DataOutputStream(echoSocket.getOutputStream());
			//获取数据输入流
            in = new DataInputStream(echoSocket.getInputStream());
        }
catch(UnknownHostException e)
{
            System.err.println("Don't know about host");
            System.exit(1);
        }
catch (IOException e)
{
            System.err.println("Couldn't get I/O for the connection");
            System.exit(1);
        }
		//将系统的标准输入设备作为数据输入流
		DataInputStream stdIn = new DataInputStream(System.in);
		String userInput;

		//读取用户输入
		while ((userInput = stdIn.readLine()) != null)
{
	//向Socket的输出流写出字符
	    	out.writeBytes(userInput);
	    	out.writeByte('\n');
			//从Socket输入流中读取，并打印
	    	System.out.println("echo: " + in.readLine());
		 }
		 //关闭输入输出流
		 out.close();
	     in.close();
	     stdIn.close();
		 //关闭套接字
	     echoSocket.close();
    }
}



例程18-4
//CommClient.java
import java.io.*;
import java.net.*;
public class CommClient 
{
    public static void main(String[] args) throws IOException 
{
		//申请Socket
        Socket comSocket = null;
		//申请数据输入输出流
        PrintStream out = null;
        DataInputStream in = null;
        try
{
	//创建Socket
            comSocket = new Socket(10.65.111.101,1800);
			//创建输出流
            out = new PrintStream(comSocket.getOutputStream());
			//创建输入流
            in = new DataInputStream(comSocket.getInputStream());
        }
catch (UnknownHostException e)
{
            System.err.println("Don't know about host");
	        System.exit(1);
        }
catch (IOException e)
{
            System.err.println("Couldn't get I/O for the connection");
	        System.exit(1);
        }
		//获取键盘输入流
        DataInputStream stdIn = new DataInputStream(System.in);
        String fromServer;
        String fromUser;
		//从键盘读入字符
	    while ((fromServer = in.readLine()) != null)
{
	        System.out.println("Server: " + fromServer);
			//如果输入bye，程序退出
	        if (fromServer.equals("Bye."))
		    break;
			//读字符
            fromUser = stdIn.readLine();
			//将客户输入发送给服务器
            if (fromUser != null)
{
                System.out.println("Client: " + fromUser);
                out.println(fromUser);
             }
	      }
		  //关闭输入输出流
	      out.close();
	      in.close();
	      stdIn.close();
		  //关闭套接字
	      comSocket.close();
    }
}



例程18-5
//CommServer.java
import java.net.*;
import java.io.*;
public class CommServer 
{
    public static void main(String[] args) throws IOException 
{
		//申请服务器ServerSocket
        ServerSocket serverSocket = null;
        try 
{
	//创建ServerSocket
            serverSocket = new ServerSocket(1800);
        }
catch (IOException e)
{
            System.err.println("Could not listen on port.");
            System.exit(1);
        }
		//申请用于连接的Socket
        Socket clientSocket = null;
        try 
{
	//获取用于连接的Socket
            clientSocket = serverSocket.accept();
        }
catch (IOException e)
{
            System.err.println("Accept failed.");
            System.exit(1);
        }
		//获取输出流
        PrintStream out = new PrintStream(
                         new BufferedOutputStream(
			      clientSocket.getOutputStream(), 1024), false);
		//获取输入流
        DataInputStream in = new DataInputStream(
                             new BufferedInputStream(
			         clientSocket.getInputStream()));
        String inputLine, outputLine;
		//设置信息交换协议
        GreetingsProtocol greetings = new GreetingsProtocol();
		//取得当前协议
        outputLine = greetings.processInput(null);
        out.println(outputLine);
        out.flush();
		//接收客户机的服务
        while ((inputLine = in.readLine()) != null) 
{
	 //处理客户机信息
             outputLine = greetings.processInput(inputLine);
             out.println(outputLine);
             out.flush();
             if (outputLine.equals("Bye."))
                break;
        }
	    //关闭输入输出流
        out.close();
        in.close();
		//关闭套接字
        clientSocket.close();
        serverSocket.close();
    }
}



例程18-6
// GreetingsProtocol.java
import java.net.*;
import java.io.*;
public class GreetingsProtocol
{
    private static final int WAITING = 0;
    private static final int SENTKNOCKKNOCK = 1;
    private static final int SENTCLUE = 2;
    private static final int ANOTHER = 3;
    private static final int NUMJOKES = 5;
    private int state = WAITING;
    private int currentJoke = 0;
    private String[] clues = 
{ "Turnip", "Little Old Lady", "Atch", "Who", "Who" };
    private String[] answers =
{ "Turnip the heat, it's cold in here!",
                                 "I didn't know you could yodel!",
                                 "Bless you!",
                                 "Is there an owl in here?",
                                 "Is there an echo in here?" };
    public String processInput(String theInput)
{
        String theOutput = null;
        if (state == WAITING)
{
            theOutput = "Knock! Knock!";
            state = SENTKNOCKKNOCK;
        }
else if (state == SENTKNOCKKNOCK)
{
            if (theInput.equalsIgnoreCase("Who's there?"))
{
                theOutput = clues[currentJoke];
                state = SENTCLUE;
            }
else
{
                theOutput = "You're supposed to say \"Who's there?\"! " +
			    "Try again. Knock! Knock!";
            }
        }
else if (state == SENTCLUE)
{
            if (theInput.equalsIgnoreCase(clues[currentJoke] + " who?"))
{
                theOutput = answers[currentJoke] + " Want another? (y/n)";
                state = ANOTHER;
            }
else
{
                theOutput = "You're supposed to say \"" + 
			    clues[currentJoke] + 
			    " who?\"" + 
			    "! Try again. Knock! Knock!";
                state = SENTKNOCKKNOCK;
            }
        } else if (state == ANOTHER)
{
            if (theInput.equalsIgnoreCase("y"))
{
                theOutput = "Knock! Knock!";
                if (currentJoke == (NUMJOKES - 1))
                    currentJoke = 0;
                else
                    currentJoke++;
                state = SENTKNOCKKNOCK;
            }
else
{
                theOutput = "Bye.";
                state = WAITING;
            }
        }
        return theOutput;
    }
}



例程18-7
//MultiServer.java
import java.net.*;
import java.io.*;
public class MultiServer 
{
    public static void main(String[] args) throws IOException 
{
        ServerSocket serverSocket = null;
        boolean listening = true;
        try 
{
            serverSocket = new ServerSocket(1800);
        }
 catch (IOException e) 
{
            System.err.println("Could not listen on port");
            System.exit(-1);
        }
        while (listening)
	    new MultiServerThread(serverSocket.accept()).start();
        serverSocket.close();
    }
}



例程18-8
//MultiServerThread.java
import java.net.*;
import java.io.*;

public class KKMultiServerThread extends Thread 
{
    private Socket socket = null;
    public KKMultiServerThread(Socket socket) 
{
        super("KKMultiServerThread");
        this.socket = socket;
    }
    public void run() 
{
        try 
{
            DataInputStream in = new DataInputStream(
                   new BufferedInputStream(socket.getInputStream()));
            PrintStream out = new PrintStream(
                   new BufferedOutputStream(socket.getOutputStream(), 1024), false);
            String inputLine, outputLine;
	        GreetingsProtocol greetings = new GreetingsProtocol();
            outputLine = greetings.processInput(null);
            out.println(outputLine);
            out.flush();
            while ((inputLine = in.readLine()) != null) 
{
                outputLine = kkp.processInput(inputLine);
                out.println(outputLine);
                out.flush();
                if (outputLine.equals("Bye"))
                    break;
            }
            out.close();
            in.close();
            socket.close();
        } 
catch (IOException e) 
{
            e.printStackTrace();
        }
    }
}



例程18-9
// QuoteServerThread.java
import java.io.*;
import java.net.*;
import java.util.*;

public class QuoteServerThread extends Thread 
{
    private DatagramSocket socket = null;
    private DataInputStream in = null;
    private boolean moreQuotes = true;
    public QuoteServerThread() throws IOException 
{
        super("QuoteServerThread");
        socket = new DatagramSocket(1800);
	    try 
{
            in = new DataInputStream(new FileInputStream("one-liners.txt"));
	    }
catch (FileNotFoundException e) 
{
            System.err.println("Could not open quote file. Serving time instead.");
        }
    }
    public void run() 
{
        while (moreQuotes) 
{
            try 
{
                byte[] buf = new byte[256];
                // receive request
                DatagramPacket packet = new DatagramPacket(buf, buf.length);
                socket.receive(packet);
		    // figure out response
                String dString = null;
                if (in == null)
                    dString = new Date().toString();
                else
                    dString = getNextQuote();
                dString.getBytes(0, dString.length(), buf, 0);
                 // send the response to the client at "address" and "port"
                InetAddress address = packet.getAddress();
                int port = packet.getPort();
                packet = new DatagramPacket(buf, buf.length, address, port);
                socket.send(packet);
            } 
catch (IOException e) 
{
                e.printStackTrace();
		        moreQuotes = false;
            }
        }
	    socket.close();
    }
    private String getNextQuote() 
{
        String returnValue = null;
        try 
{
            if ((returnValue = in.readLine()) == null) 
{
                in.close();
		        moreQuotes = false;
                returnValue = "No more quotes. Goodbye.";
            }
        } 
catch (IOException e) 
{
            returnValue = "IOException occurred in server.";
        }
        return returnValue;
    }
}



例程18-10
// QuoteClient.java
import java.io.*;
import java.net.*;
import java.util.*;
public class QuoteClient 
{
    public static void main(String[] args) throws IOException 
{
        if (args.length != 1) 
{
             System.out.println("Usage: java QuoteClient <hostname>");
             return;
        }
	    // get a datagram socket
        DatagramSocket socket = new DatagramSocket();
	   // send request
	   byte[] buf = new byte[256];
	   InetAddress address = InetAddress.getByName(args[0]);
	   DatagramPacket packet = 
new DatagramPacket(buf, buf.length, address, 1800);
	   socket.send(packet);

	   // get response
	   packet = new DatagramPacket(buf, buf.length);
	   socket.receive(packet);
	   // display response
	   String received = new String(packet.getData(), 0);
	   System.out.println("Quote of the Moment: " + received);
	   socket.close();
    }
}



例程18-11
//QuoteServer.java
public class QuoteServer 
{
    public static void main(String[] args) throws java.io.IOException 
{
        new QuoteServerThread().start();
    }
}