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
");
            sb.append("Content-Type:text/html

");
            //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("
"));
            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。