socket笔记

import java.io.*;import java.net.*;import java.util.Scanner;import java.util.regex.Matcher;import java.util.regex.Pattern;public class Main {    public static       String SERVER_HOST         = "";    public static       String CLIENT_HOST         = "";    public static final int    SERVER_RECEIVE_PORT = 9344;    public static final int    CLIENT_RECEIVE_PORT = 9345;    public static ServerSocket serverSocket;    public static Socket       receiveSocket;    public static Socket sendSocket;    public static Scanner scanner   = new Scanner(System.in);    public static boolean isQuitApp = false;    public static String  role      = "";    static class ReceiveThread extends Thread {        public ReceiveThread() {            super("RECEIVE_THREAD");        }        @Override        public void run() {            super.run();            try {                receiveSocket = serverSocket.accept();                if ("1".equals(role)) {                    InetSocketAddress isa = (InetSocketAddress) receiveSocket.getRemoteSocketAddress();                    CLIENT_HOST = isa.getAddress().getHostAddress();                    System.out.println("收到来自IP: " + CLIENT_HOST + " 的连接！");                } else if ("2".equals(role)) {                    System.out.println("收到连接！");                }                System.out.println("建立连接成功！");            } catch (IOException ioe) {                ioe.printStackTrace();            }            InputStream is = null;            try {                is = receiveSocket.getInputStream();                byte[] buffer = new byte[65535];                while (true) {                    int count = is.read(buffer);                    String line = new String(buffer, 0, count);                    if ("exit".equals(line)) {                        break;                    }                    System.out.println("对方：" + line);                }            } catch (IOException ioe) {                ioe.printStackTrace();            } finally {                closeQuietly(is);                closeQuietly(receiveSocket);            }        }    }    static class SendThread extends Thread {        private SendThread() {            super("SEND_THREAD");        }        @Override        public void run() {            super.run();            try {                if ("1".equals(role)) {                    while (CLIENT_HOST.length() == 0) {                        try {                            Thread.sleep(1000);                        } catch (InterruptedException ie) {                            ie.printStackTrace();                        }                    }                    sendSocket = new Socket(CLIENT_HOST, CLIENT_RECEIVE_PORT);                } else if ("2".equals(role)) {                    if (SERVER_HOST.length() == 0) {                        throw new RuntimeException("SERVER_HOST is empty");                    }                    sendSocket = new Socket(SERVER_HOST, SERVER_RECEIVE_PORT);                }            } catch (UnknownHostException uhe) {                uhe.printStackTrace();            } catch (IOException ioe) {                ioe.printStackTrace();            }            OutputStream os = null;            Writer writer = null;            BufferedWriter bw = null;            try {                os = sendSocket.getOutputStream();                writer = new OutputStreamWriter(os);                bw = new BufferedWriter(writer);                while (scanner.hasNext()) {                    String line = scanner.nextLine();                    bw.write(line);                    bw.flush();                    if ("exit".equals(line.trim())) {                        break;                    }                    if ("quitApp".equals(line.trim())) {                        isQuitApp = true;                        break;                    }                }            } catch (IOException ioe) {                ioe.printStackTrace();            } finally {                closeQuietly(os);                closeQuietly(writer);                closeQuietly(bw);                closeQuietly(sendSocket);            }        }    }    public static void main(String[] args) {        try {            printScreen();            try {                while (scanner.hasNext()) {                    String line = scanner.nextLine();                    if ("1".equals(line.trim())) {                        role = "1";                        serverSocket = new ServerSocket(SERVER_RECEIVE_PORT);                        System.out.println("已成为服务端！");                        break;                    } else if ("2".equals(line.trim())) {                        role = "2";                        serverSocket = new ServerSocket(CLIENT_RECEIVE_PORT);                        System.out.println("已成为客户端！");                        System.out.println("请输入服务端ip地址:");                        while (scanner.hasNext()) {                            String serverIp = scanner.nextLine().trim();                            if (isIpv4(serverIp)) {                                SERVER_HOST = serverIp;                                break;                            } else {                                System.out.println("ip格式错误");                                System.out.println("请输入服务端ip地址:");                            }                        }                        break;                    } else {                        System.out.println("输入不合法！");                        printScreen();                    }                }            } catch (IOException ioe) {                ioe.printStackTrace();            }            if (serverSocket != null) {                new ReceiveThread().start();                new SendThread().start();            }            while (!isQuitApp) {                try {                    Thread.sleep(1000);                } catch (InterruptedException ie) {                    ie.printStackTrace();                }            }        } catch (Exception e) {            e.printStackTrace();        } finally {            closeQuietly(serverSocket);            closeQuietly(receiveSocket);            closeQuietly(sendSocket);        }    }    private static void printScreen() {        System.out.println("请输入(您的IP为: " + getIp() + " ):");        System.out.println("    1 --> 成为服务端");        System.out.println("    2 --> 成为客户端");    }    private static String getIp() {        try {            InetAddress ia = InetAddress.getLocalHost();            return ia.getHostAddress();        } catch (UnknownHostException uhe) {            uhe.printStackTrace();            return "";        }    }    public static void closeQuietly(Closeable closeable) {        try {            if (closeable != null) {                closeable.close();            }        } catch (IOException var2) {            ;        }    }    public static void closeQuietly(ServerSocket sock) {        if (sock != null && !sock.isClosed()) {            try {                sock.close();            } catch (IOException var2) {                ;            }        }    }    public static boolean isIpv4(String ipAddress) {        String ip = "^(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|[1-9])\\."                    + "(00?\\d|1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\."                    + "(00?\\d|1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\."                    + "(00?\\d|1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)$";        Pattern pattern = Pattern.compile(ip);        Matcher matcher = pattern.matcher(ipAddress);        return matcher.matches();    }}