Java Socket实战之五:使用加密协议传输对象

前面几篇博文提到了Socket中一些常用的用法，但是对于一些有安全要求的应用就需要加密传输的数据，此时就需要用到SSLSocket了。

还是一样需要一个实现了java.io.Serializable接口的简单Java对象：

package com.googlecode.garbagecan.test.socket.ssl;

 public class User implements java.io.Serializable {
     private static final long serialVersionUID = 1L;
     private String name;
     private String password;

     public User() {

    }

     public User(String name, String password) {
         this.name = name;
         this.password = password;
    }

     public String getName() {
         return name;
    }

     public void setName(String name) {
         this.name = name;
    }

     public String getPassword() {
         return password;
    }

     public void setPassword(String password) {
         this.password = password;
    }

}

SSL Server类，这里需要用到ServerSocketFactory类来创建SSLServerSocket类实例，然后在通过SSLServerSocket来获取SSLSocket实例，这里考虑到面向对象中的面向接口编程的理念，所以代码中并没有出现SSLServerSocket和SSLSocket，而是用了他们的父类ServerSocket和Socket。在获取到ServerSocket和Socket实例以后，剩下的代码就和不使用加密方式一样了。

package com.googlecode.garbagecan.test.socket.ssl;

 import java.io.BufferedInputStream;
 import java.io.IOException;
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.net.ServerSocket;
 import java.net.Socket;
 import java.util.logging.Level;
 import java.util.logging.Logger;

 import javax.net.ServerSocketFactory;
 import javax.net.ssl.SSLServerSocketFactory;

 public class MyServer {

     private final static Logger logger = Logger.getLogger(MyServer.class.getName());

     public static void main(String[] args) {
         try {
            ServerSocketFactory factory = SSLServerSocketFactory.getDefault();
             ServerSocket server = factory.createServerSocket(10000);

             while (true) {
                Socket socket = server.accept();
                invoke(socket);
            }
         } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

     private static void invoke(final Socket socket) throws IOException {
         new Thread(new Runnable() {
             public void run() {
                 ObjectInputStream is = null;
                 ObjectOutputStream os = null;
                 try {
                     is = new ObjectInputStream(new BufferedInputStream(socket.getInputStream()));
                     os = new ObjectOutputStream(socket.getOutputStream());

                    Object obj = is.readObject();
                    User user = (User)obj;
                     System.out.println("user: " + user.getName() + "/" + user.getPassword());

                     user.setName(user.getName() + "_new");
                     user.setPassword(user.getPassword() + "_new");

                    os.writeObject(user);
                    os.flush();
                 } catch (IOException ex) {
                     logger.log(Level.SEVERE, null, ex);
                 } catch(ClassNotFoundException ex) {
                     logger.log(Level.SEVERE, null, ex);
                 } finally {
                     try {
                        is.close();
                     } catch(Exception ex) {}
                     try {
                        os.close();
                     } catch(Exception ex) {}
                     try {
                        socket.close();
                     } catch(Exception ex) {}
                }
            }
        }).start();
    }
}

SSL Client类和SSL Server类类似，只是将其中获取Socket的方式有所变化，其余的代码也和不使用加密方式一样。

package com.googlecode.garbagecan.test.socket.ssl;

 import java.io.BufferedInputStream;
 import java.io.IOException;
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.net.Socket;
 import java.util.logging.Level;
 import java.util.logging.Logger;

 import javax.net.SocketFactory;
 import javax.net.ssl.SSLSocketFactory;

 public class MyClient {

 private final static Logger logger = Logger.getLogger(MyClient.class.getName());

     public static void main(String[] args) throws Exception {
         for (int i = 0; i < 100; i++) {
             Socket socket = null;
             ObjectOutputStream os = null;
             ObjectInputStream is = null;

             try {
                SocketFactory factory = SSLSocketFactory.getDefault();
                 socket = factory.createSocket("localhost", 10000);

                 os = new ObjectOutputStream(socket.getOutputStream());
                 User user = new User("user_" + i, "password_" + i);
                os.writeObject(user);
                os.flush();

                 is = new ObjectInputStream(new BufferedInputStream(socket.getInputStream()));
                Object obj = is.readObject();
                 if (obj != null) {
                    user = (User)obj;
                     System.out.println("user: " + user.getName() + "/" + user.getPassword());
                }
             } catch(IOException ex) {
                 logger.log(Level.SEVERE, null, ex);
             } finally {
                 try {
                    is.close();
                 } catch(Exception ex) {}
                 try {
                    os.close();
                 } catch(Exception ex) {}
                 try {
                    socket.close();
                 } catch(Exception ex) {}
            }
        }
    }
}

代码写完了，下面就需要产生keystore文件了，运行下面的命令

keytool -genkey -alias mysocket -keyalg RSA -keystore mysocket.jks

在提示输入项中，密码项自己给定，其它都不改直接回车，这里我使用的密码是“mysocket”。

运行Server

java -Djavax.net.ssl.keyStore=mysocket.jks -Djavax.net.ssl.keyStorePassword=mysocket com.googlecode.garbagecan.test.socket.ssl.MyServer

运行Client

java -Djavax.net.ssl.trustStore=mysocket.jks  -Djavax.net.ssl.trustStorePassword=mysocket com.googlecode.garbagecan.test.socket.ssl.MyClient