简易非阻塞http服务器

• 说明

        需要理解阻塞和非阻塞的区别，特别要注意非阻塞和异步不是一个概念，这个很容易弄错。云盘里面netty的书会讲这几个方面的区别，nodejs深入浅出关于异步编程章节里面        也会讲到网络通信底层的知识,可以看看下面文章：

http://blog.csdn.net/hguisu/article/details/7453390

http://www.cnblogs.com/dolphin0520/p/3916526.html

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• Handler接口类

 package study.socket.tcp.nonblock.simpleserver;

 import java.io.IOException;
 import java.nio.channels.SelectionKey;

 public interface Handler {

     public void handle(SelectionKey selectionKey) throws IOException;
 }

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• 请求连接Handler实现类

 package study.socket.tcp.nonblock.simpleserver;

 import java.io.IOException;
 import java.nio.channels.SelectionKey;
 import java.nio.channels.ServerSocketChannel;
 import java.nio.channels.SocketChannel;

 public class AcceptHandler implements Handler{

     @Override
     public void handle(SelectionKey selectionKey) throws IOException {
         System.out.println("开始处理连接请求");
         try {
             Thread.sleep(60000);
         } catch (InterruptedException e) {
             e.printStackTrace();
         }
         //得到事件发生的通道
         ServerSocketChannel ssc = (ServerSocketChannel) selectionKey.channel();
         //获得和客户端连接的通道
         SocketChannel socketChannel = ssc.accept();
         //设置曾非阻塞模式
         socketChannel.configureBlocking(false);
         //在和客户端连接成功之后,为了可以接收到客户端的信息,需要给通道设置读权限
         socketChannel.register(selectionKey.selector(), SelectionKey.OP_READ, new RequestHandler());
         System.out.println("连接成功");
     }

 }

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•  请求处理Handler实现类

 package study.socket.tcp.nonblock.simpleserver;

 import java.io.FileInputStream;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.CharBuffer;
 import java.nio.channels.FileChannel;
 import java.nio.channels.SelectionKey;
 import java.nio.channels.SocketChannel;
 import java.nio.charset.Charset;
 import java.nio.charset.CharsetDecoder;

 public class RequestHandler implements Handler{

     @Override
     public void handle(SelectionKey selectionKey) throws IOException {
         FileInputStream fis = null;
         SocketChannel socketChannel = null;
         try {
             socketChannel = (SocketChannel) selectionKey.channel();
             ByteBuffer byteBuffer = ByteBuffer.allocate(1024);
             socketChannel.read(byteBuffer);
             byte[] data = byteBuffer.array();
             String msg = new String(data);
             System.out.println("接收客户端的消息：" + msg);
             byteBuffer.flip();
             String request = decode(byteBuffer);
             System.out.println("客户端请求消息：" + request);
             //生成http响应消息
             StringBuffer sb = new StringBuffer("HTTP/1.1 200 OK\r\n");
             sb.append("Content-Type:text/html\r\n\r\n");
             //发送http响应第一行和响应头
             socketChannel.write(encode(sb.toString()));

             //获取http请求的第一行
             String firstLineOfRequst = request.substring(0, request.indexOf("\r\n"));
             String filePath = SimpleHttpServer.class.getResource("/").getPath();
             System.out.println("路径：" + filePath);
             System.out.println("测试");
             if(firstLineOfRequst.indexOf("login.html") != -1) {
                 fis = new FileInputStream(filePath + "study/socket/block/httpserver/login.html");
             }else {
                 fis = new FileInputStream(filePath + "study/socket/block/httpserver/hello.html");
             }
             FileChannel fc = fis.getChannel();
             fc.transferTo(0, fc.size(), socketChannel);
         } catch(Exception e){
             e.printStackTrace();
         }finally {
             if(fis != null) {
                 try {
                     fis.close();
                 } catch (IOException e1) {
                     e1.printStackTrace();
                 }
             }
             if(socketChannel != null) {
                 try {
                     socketChannel.close();
                 } catch (IOException e1) {
                     e1.printStackTrace();
                 }
             }
         }
     }
     //编码
     private String decode(ByteBuffer bb) throws Exception{
         Charset charset  =  Charset.forName("utf-8");
         CharsetDecoder decoder  =  charset.newDecoder();
         CharBuffer charBuffer  =  decoder.decode(bb);
         System.out.println( " charBuffer= "   +  charBuffer);
         System.out.println(charBuffer.toString());
         System.out.println("编码");
         return  charBuffer.toString();
     }
     //解码
     private ByteBuffer encode(String str) {
         System.out.println("解码");
         return ByteBuffer.wrap(str.getBytes());
     }
 }

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•  nio编写的服务端类

 package study.socket.tcp.nonblock.simpleserver;

 import java.io.IOException;
 import java.net.InetSocketAddress;
 import java.nio.channels.SelectionKey;
 import java.nio.channels.Selector;
 import java.nio.channels.ServerSocketChannel;
 import java.util.Iterator;

 /**
  * 非阻塞式简易http服务器
  * @author yj
  *
  */
 public class SimpleHttpServer {

     private int port = 8080;
     private Selector selector;

     public void initServer() throws IOException{
         //打开服务器套接字通道
         ServerSocketChannel ssc = ServerSocketChannel.open();
         //将服务端套接字通道连接方式改为非阻塞模式
         ssc.configureBlocking(false);
         //绑定端口
         ssc.socket().bind(new InetSocketAddress(port));
         //打开通道选择器
         this.selector = Selector.open();
         //将服务器套接字通道的OP_ACCEPT事件注册到通道选择器上
         ssc.register(selector, SelectionKey.OP_ACCEPT, new AcceptHandler());
     }

     public void service() throws IOException{
         while(true) {
             int n = selector.select();
             System.out.println("开始处理请求");
             if(n == 0) continue;
             //获取通道选择器事件
             Iterator<SelectionKey> itr = this.selector.selectedKeys().iterator();
             while(itr.hasNext()) {
                 SelectionKey sk = null;
                 try {
                     sk = itr.next();
                     itr.remove();
                     Handler handler = (Handler) sk.attachment();
                     handler.handle(sk);
                 } catch(Exception e) {
                     e.printStackTrace();
                 }
             }
             System.out.println("请求处理完成");
         }
     }

     public static void main(String[] args) {
         try {
             SimpleHttpServer2 nioServer = new SimpleHttpServer2();
             nioServer.initServer();
             nioServer.service();
         } catch (Exception e) {
             e.printStackTrace();
         }
     }
 }

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• html文件

html文件使用《简易阻塞http服务器》中的两个html文件，注意文件目录与上面类文件所在目录一致。

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• 测试

启动main方法，浏览器输入：http://ip:port/或http://ip:port/hello.html访问hello.html,输入http://ip:port/login.html访问login.html.

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• 云盘资料

       http://yunpan.cn/cwJGv4vUm9kTf  访问密码 a74b     里面包含了io.socket和nio.socket的一些简单代码，还有上面说的netty的书。