IO NIO 区别请看 ： http://blog.csdn.net/jiangtao_st/article/details/38041479
一、基于Nio的 Server ,过程略复杂，但是无疑这样的效率高；代码中得注释比较详细，请看注释说明
package com.zhuoxuan.net.nio;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.nio.ByteBuffer;
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.Random;
import java.util.Set;
/**
*
* <p>
* 基于nio的Server
* </p>
*
* @author 卓轩
* @创建时间：2014年7月7日
* @version： V1.0
*/
public class NioServer {
private final int port = 8787;
private final int BLOCK_SIZE = 4096;
private Selector selector;
private ByteBuffer receiveBuffer = ByteBuffer.allocate(BLOCK_SIZE);
private ByteBuffer sendBuffer = ByteBuffer.allocate(BLOCK_SIZE);
//构造函数
public NioServer() throws IOException {
//打开服务器套接字通道
ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
//服务器配置为非阻塞模式
serverSocketChannel.configureBlocking(false);
//获取与通道关联的 ServerSocket对象
ServerSocket serverSocket = serverSocketChannel.socket();
//绑定端口
serverSocket.bind(new InetSocketAddress(port));
//打开一个选择器
selector = Selector.open();
//注册到selector上，等待连接
serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);
System.out.println("Server:init successfuly.");
}
/**
* 监听端口
*/
private void linstenr() throws Exception{
while (true) {
//选择一组键
selector.select();
//返回获取选择的键集
Set<SelectionKey> selectionKeys = selector.selectedKeys();
if(selectionKeys.isEmpty()){
continue;
}
//遍历，循环处理请求的键集
Iterator<SelectionKey> iterator = selectionKeys.iterator();
while (iterator.hasNext()) {
SelectionKey selectionKey = (SelectionKey) iterator.next();
iterator.remove();
handlerKey(selectionKey);
}
Thread.sleep(4000);
}
}
/**
* 处理对应的 SelectionKey
* @param selectionKey
*/
private void handlerKey(SelectionKey selectionKey) throws IOException{
ServerSocketChannel server;
SocketChannel client;
// 测试此键的通道是否已准备好接受新的套接字连接
if(selectionKey.isAcceptable()){
//此键对应的关联通道
server = (ServerSocketChannel)selectionKey.channel();
//接受到此通道套接字的连接
client = server.accept();
//配置为非阻塞
client.configureBlocking(false);
//注册到selector 等待连接
client.register(selector, SelectionKey.OP_READ);
}
else if (selectionKey.isReadable()) {
client = (SocketChannel)selectionKey.channel();
//将缓冲区清空，下面读取
receiveBuffer.clear();
//将客户端发送来的数据读取到 buffer中
int count = client.read(receiveBuffer);
if(count >0){
String receiveMessage = new String(receiveBuffer.array(),0,count);
System.out.println("Server:接受客户端的数据:" + receiveMessage);
client.register(selector, SelectionKey.OP_WRITE);
}
}
else if (selectionKey.isWritable()) {
//发送消息buffer 清空
sendBuffer.clear();
//返回该键对应的通道
client = (SocketChannel)selectionKey.channel();
String sendMessage = "Send form Server...Hello... "+new Random().nextInt(100)+" .";
//向缓冲区中写入数据
sendBuffer.put(sendMessage.getBytes());
//put了数据，标志位被改变
sendBuffer.flip();
//数据输出到通道
client.write(sendBuffer);
System.out.println("Server:服务器向客户端发送数据:" + sendMessage);
client.register(selector, SelectionKey.OP_READ);
}
}
public static void main(String[] args) {
try {
NioServer nioServer = new NioServer();
nioServer.linstenr();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
package com.zhuoxuan.net.nio;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import java.util.Iterator;
import java.util.Set;
/**
*
* <p>
* nio client
* </p>
*
* @author 卓轩
* @创建时间：2014年7月7日
* @version： V1.0
*/
public class NioClient {
private static final int BLOCK_SIZE = 4096;
private static ByteBuffer sendBuffer = ByteBuffer.allocate(BLOCK_SIZE);
private static ByteBuffer receiveBuffer = ByteBuffer.allocate(BLOCK_SIZE);
private static final InetSocketAddress SERVER_ADDRESS = new InetSocketAddress("127.0.0.1",8787);
public static void main(String[] args) {
try {
//打开socket通道
SocketChannel socketChannel = SocketChannel.open();
//设置为非阻塞模式
socketChannel.configureBlocking(false);
//打开选择器
Selector selector = Selector.open();
//向selector 选择器注册此通道
socketChannel.register(selector, SelectionKey.OP_CONNECT);
//链接
socketChannel.connect(SERVER_ADDRESS);
SocketChannel client;
while (true) {
//选择一组键
selector.select();
//返回此选择器的已选择键集
Set<SelectionKey> selectionKeys = selector.selectedKeys();
Iterator<SelectionKey> iterator = selectionKeys.iterator();
//遍历对应的 SelectionKey 处理
while (iterator.hasNext()) {
SelectionKey selectionKey = (SelectionKey) iterator.next();
//判断此键的通道是否已完成其套接字连接操作
if (selectionKey.isConnectable()) {
System.out.println("Client: already connected.");
client = (SocketChannel)selectionKey.channel();
//判断该通道是否进行连接过程、完成连接过程
if(client.isConnectionPending()){
client.finishConnect();
sendBuffer.clear();
sendBuffer.put("hello nio server".getBytes());
sendBuffer.flip();
client.write(sendBuffer); //将数据写入该通道
client.register(selector, SelectionKey.OP_READ);
}
}
else if(selectionKey.isReadable()){
//获取该键中对应的通道
client = (SocketChannel)selectionKey.channel();
receiveBuffer.clear();
int count = client.read(receiveBuffer);
if(count > 0){
String receiveMessage = new String(receiveBuffer.array(),0,count);
System.out.println("Client：接收到来自Server的消息，" + receiveMessage);
client.register(selector, SelectionKey.OP_WRITE);
}
}
else if(selectionKey.isWritable()){
sendBuffer.clear();
client = (SocketChannel) selectionKey.channel();
String sendText = "hello server,key..";
sendBuffer.put(sendText.getBytes());
//将缓冲区各标志复位,因为向里面put了数据标志被改变要想从中读取数据发向服务器,就要复位
sendBuffer.flip();
client.write(sendBuffer);
System.out.println("Client:客户端向服务器端发送数据--："+sendText);
client.register(selector, SelectionKey.OP_READ);
}
}
selectionKeys.clear();
Thread.sleep(3000);
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
Java网络编程-Nio 实例代码,布布扣,bubuko.com
原文地址：http://blog.csdn.net/jiangtao_st/article/details/38041867
