Java使用NIO包实现Socket通信的实例代码

package com.googlecode.garbagecan.test.socket;  import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream;  public class SerializableUtil {      public static byte[] toBytes(Object object) {     ByteArrayOutputStream baos = new ByteArrayOutputStream();     ObjectOutputStream oos = null;     try {       oos = new ObjectOutputStream(baos);       oos.writeObject(object);       byte[] bytes = baos.toByteArray();       return bytes;     } catch(IOException ex) {       throw new RuntimeException(ex.getMessage(), ex);     } finally {       try {         oos.close();       } catch (Exception e) {}     }   }      public static Object toObject(byte[] bytes) {     ByteArrayInputStream bais = new ByteArrayInputStream(bytes);     ObjectInputStream ois = null;     try {       ois = new ObjectInputStream(bais);       Object object = ois.readObject();       return object;     } catch(IOException ex) {       throw new RuntimeException(ex.getMessage(), ex);     } catch(ClassNotFoundException ex) {       throw new RuntimeException(ex.getMessage(), ex);     } finally {       try {         ois.close();       } catch (Exception e) {}     }   } } 

package com.googlecode.garbagecan.test.socket.nio;  import java.io.Serializable;  public class MyRequestObject implements Serializable {    private static final long serialVersionUID = 1L;    private String name;      private String value;    private byte[] bytes;      public MyRequestObject(String name, String value) {     this.name = name;     this.value = value;     this.bytes = new byte[1024];   }      public String getName() {     return name;   }    public void setName(String name) {     this.name = name;   }    public String getValue() {     return value;   }    public void setValue(String value) {     this.value = value;   }      @Override   public String toString() {     StringBuffer sb = new StringBuffer();     sb.append("Request [name: " + name + ", value: " + value + ", bytes: " + bytes.length+ "]");     return sb.toString();   } }  package com.googlecode.garbagecan.test.socket.nio;  import java.io.Serializable;  public class MyResponseObject implements Serializable {    private static final long serialVersionUID = 1L;    private String name;      private String value;    private byte[] bytes;      public MyResponseObject(String name, String value) {     this.name = name;     this.value = value;     this.bytes = new byte[1024];   }      public String getName() {     return name;   }    public void setName(String name) {     this.name = name;   }    public String getValue() {     return value;   }    public void setValue(String value) {     this.value = value;   }      @Override   public String toString() {     StringBuffer sb = new StringBuffer();     sb.append("Response [name: " + name + ", value: " + value + ", bytes: " + bytes.length+ "]");     return sb.toString();   } } 

package com.googlecode.garbagecan.test.socket.nio;  import java.io.ByteArrayOutputStream; import java.io.IOException; import java.net.InetSocketAddress; import java.nio.ByteBuffer; import java.nio.channels.ClosedChannelException; import java.nio.channels.SelectionKey; import java.nio.channels.Selector; import java.nio.channels.ServerSocketChannel; import java.nio.channels.SocketChannel; import java.util.Iterator; import java.util.logging.Level; import java.util.logging.Logger;  import com.googlecode.garbagecan.test.socket.SerializableUtil;  public class MyServer3 {    private final static Logger logger = Logger.getLogger(MyServer3.class.getName());      public static void main(String[] args) {     Selector selector = null;     ServerSocketChannel serverSocketChannel = null;          try {       // Selector for incoming time requests       selector = Selector.open();        // Create a new server socket and set to non blocking mode       serverSocketChannel = ServerSocketChannel.open();       serverSocketChannel.configureBlocking(false);              // Bind the server socket to the local host and port       serverSocketChannel.socket().setReuseAddress(true);       serverSocketChannel.socket().bind(new InetSocketAddress(10000));              // Register accepts on the server socket with the selector. This       // step tells the selector that the socket wants to be put on the       // ready list when accept operations occur, so allowing multiplexed       // non-blocking I/O to take place.       serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);          // Here's where everything happens. The select method will       // return when any operations registered above have occurred, the       // thread has been interrupted, etc.       while (selector.select() > 0) {         // Someone is ready for I/O, get the ready keys         Iterator<SelectionKey> it = selector.selectedKeys().iterator();            // Walk through the ready keys collection and process date requests.         while (it.hasNext()) {           SelectionKey readyKey = it.next();           it.remove();                      // The key indexes into the selector so you           // can retrieve the socket that's ready for I/O           execute((ServerSocketChannel) readyKey.channel());         }       }     } catch (ClosedChannelException ex) {       logger.log(Level.SEVERE, null, ex);     } catch (IOException ex) {       logger.log(Level.SEVERE, null, ex);     } finally {       try {         selector.close();       } catch(Exception ex) {}       try {         serverSocketChannel.close();       } catch(Exception ex) {}     }   }    private static void execute(ServerSocketChannel serverSocketChannel) throws IOException {     SocketChannel socketChannel = null;     try {       socketChannel = serverSocketChannel.accept();       MyRequestObject myRequestObject = receiveData(socketChannel);       logger.log(Level.INFO, myRequestObject.toString());              MyResponseObject myResponseObject = new MyResponseObject(           "response for " + myRequestObject.getName(),            "response for " + myRequestObject.getValue());       sendData(socketChannel, myResponseObject);       logger.log(Level.INFO, myResponseObject.toString());     } finally {       try {         socketChannel.close();       } catch(Exception ex) {}     }   }      private static MyRequestObject receiveData(SocketChannel socketChannel) throws IOException {     MyRequestObject myRequestObject = null;     ByteArrayOutputStream baos = new ByteArrayOutputStream();     ByteBuffer buffer = ByteBuffer.allocate(1024);          try {       byte[] bytes;       int size = 0;       while ((size = socketChannel.read(buffer)) >= 0) {         buffer.flip();         bytes = new byte[size];         buffer.get(bytes);         baos.write(bytes);         buffer.clear();       }       bytes = baos.toByteArray();       Object obj = SerializableUtil.toObject(bytes);       myRequestObject = (MyRequestObject)obj;     } finally {       try {         baos.close();       } catch(Exception ex) {}     }     return myRequestObject;   }    private static void sendData(SocketChannel socketChannel, MyResponseObject myResponseObject) throws IOException {     byte[] bytes = SerializableUtil.toBytes(myResponseObject);     ByteBuffer buffer = ByteBuffer.wrap(bytes);     socketChannel.write(buffer);   } } 

package com.googlecode.garbagecan.test.socket.nio;  import java.io.ByteArrayOutputStream; import java.io.IOException; import java.net.InetSocketAddress; import java.net.SocketAddress; import java.nio.ByteBuffer; import java.nio.channels.SocketChannel; import java.util.logging.Level; import java.util.logging.Logger;  import com.googlecode.garbagecan.test.socket.SerializableUtil;  public class MyClient3 {    private final static Logger logger = Logger.getLogger(MyClient3.class.getName());      public static void main(String[] args) throws Exception {     for (int i = 0; i < 100; i++) {       final int idx = i;       new Thread(new MyRunnable(idx)).start();     }   }      private static final class MyRunnable implements Runnable {          private final int idx;      private MyRunnable(int idx) {       this.idx = idx;     }      public void run() {       SocketChannel socketChannel = null;       try {         socketChannel = SocketChannel.open();         SocketAddress socketAddress = new InetSocketAddress("localhost", 10000);         socketChannel.connect(socketAddress);          MyRequestObject myRequestObject = new MyRequestObject("request_" + idx, "request_" + idx);         logger.log(Level.INFO, myRequestObject.toString());         sendData(socketChannel, myRequestObject);                  MyResponseObject myResponseObject = receiveData(socketChannel);         logger.log(Level.INFO, myResponseObject.toString());       } catch (Exception ex) {         logger.log(Level.SEVERE, null, ex);       } finally {         try {           socketChannel.close();         } catch(Exception ex) {}       }     }      private void sendData(SocketChannel socketChannel, MyRequestObject myRequestObject) throws IOException {       byte[] bytes = SerializableUtil.toBytes(myRequestObject);       ByteBuffer buffer = ByteBuffer.wrap(bytes);       socketChannel.write(buffer);       socketChannel.socket().shutdownOutput();     }      private MyResponseObject receiveData(SocketChannel socketChannel) throws IOException {       MyResponseObject myResponseObject = null;       ByteArrayOutputStream baos = new ByteArrayOutputStream();              try {         ByteBuffer buffer = ByteBuffer.allocateDirect(1024);         byte[] bytes;         int count = 0;         while ((count = socketChannel.read(buffer)) >= 0) {           buffer.flip();           bytes = new byte[count];           buffer.get(bytes);           baos.write(bytes);           buffer.clear();         }         bytes = baos.toByteArray();         Object obj = SerializableUtil.toObject(bytes);         myResponseObject = (MyResponseObject) obj;         socketChannel.socket().shutdownInput();       } finally {         try {           baos.close();         } catch(Exception ex) {}       }       return myResponseObject;     }   } }