简单的 http 服务器

简单的基于socket和NIO的 http server示例：

项目路径：https://github.com/windwant/windwant-demo/tree/master/httpserver-demo

1. Request：

package org.windwant.httpserver;

import java.io.IOException;
import java.io.InputStream;

/**
 * Created by windwant on 2016/6/12.
 */
public class Request {

    private InputStream in;

    public String getUri() {
        return uri;
    }

    private String uri;

    public Request(){}

    public Request(InputStream in){
        this.in = in;
    }

    public void read(){
        StringBuffer sb = new StringBuffer();
        int i = 0;
        byte[] b = new byte[2048];
        try {
            i = in.read(b);
            for (int j = 0; j < i; j++) {
                sb.append((char)b[j]);
            }
            takeUri(sb);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void takeUri(StringBuffer sb){
        int i = sb.indexOf(" ");
        if(i > 0){
            int j = sb.indexOf(" ", i + 1);
            if(j > 0){
                uri = sb.substring(i + 1, j).toString();
                System.out.println("http request uri: " + uri);
                if(!(uri.endsWith("/index.html") || uri.endsWith("/test.jpg"))){
                    uri = "/404.html";
                    System.out.println("http request uri rewrite: " + uri);
                }
            }
        }
    }

}

2. Response：

package org.windwant.httpserver;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.nio.channels.SocketChannel;

/**
 * Created by windwant on 2016/6/12.
 */
public class Response {
    private static final int BUFFER_SIZE = 1024;

    public void setRequest(Request request) {
        this.request = request;
    }

    Request request;

    OutputStream out;

    SocketChannel osc;

    public Response(OutputStream out){
        this.out = out;
    }

    public Response(SocketChannel osc){
        this.osc = osc;
    }

    public void response(){
        byte[] b = new byte[BUFFER_SIZE];
        File file = new File(HttpServer.WEB_ROOT, request.getUri());
        try {
            StringBuilder sb = new StringBuilder();
            if(file.exists()){
                FileInputStream fi = new FileInputStream(file);
                int ch = 0;
                while ((ch = fi.read(b, 0, BUFFER_SIZE)) > 0){
                    out.write(b, 0, ch);
                }
                out.flush();
            }else{
                sb.append("HTTP/1.1 404 File Not Found 
");
                sb.append("Content-Type: text/html
");
                sb.append("Content-Length: 24
" );
                sb.append("
" );
                sb.append("<h1>File Not Found!</h1>");
                out.write(sb.toString().getBytes());
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void responseNIO(){
        byte[] b = new byte[BUFFER_SIZE];
        File file = new File(HttpServer.WEB_ROOT, request.getUri());
        try {
            StringBuilder sb = new StringBuilder();
            if(file != null && file.exists()){
                FileInputStream fi = new FileInputStream(file);
                while (fi.read(b) > 0){
                    osc.write(ByteBuffer.wrap(b));
                    b = new byte[BUFFER_SIZE];
                }
            }else{
                sb.append("HTTP/1.1 404 File Not Found 
");
                sb.append("Content-Type: text/html
");
                sb.append("Content-Length: 24
" );
                sb.append("
" );
                sb.append("<h1>File Not Found!</h1>");
                osc.write(ByteBuffer.wrap(sb.toString().getBytes()));
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}

3. HttpServer：

package org.windwant.httpserver;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * Created by windwant on 2016/6/12.
 */
public class HttpServer {
    public static final String WEB_ROOT = System.getProperty("user.dir") + "\src\test\resources\webroot";
    public static final int SERVER_PORT = 8888;
    public static final String SERVER_IP = "127.0.0.1";

    public static void main(String[] args) {
        HttpServer httpServer = new HttpServer();
        httpServer.await();
    }

    public void await(){
        ServerSocket serverSocket = null;
        try {
            serverSocket = new ServerSocket(SERVER_PORT, 1, InetAddress.getByName(SERVER_IP));
            while (true){
                Socket socket = serverSocket.accept();
                InputStream in = socket.getInputStream();
                OutputStream out = socket.getOutputStream();
                Request request = new Request(in);
                request.read();

                Response response = new Response(out);
                response.setRequest(request);
                response.response();
                socket.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

4. HttpNIOServer：

package org.windwant.httpserver;

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.Set;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * Created by windwant on 2016/6/13.
 */
public class HttpNIOServer {

    private ServerSocketChannel serverSocketChannel;

    private ServerSocket serverSocket;

    private Selector selector;

    Request request;

    private ExecutorService es;

    private static final Integer SERVER_PORT = 8888;

    public void setShutdown(boolean shutdown) {
        this.shutdown = shutdown;
    }

    private boolean shutdown = false;


    public static void main(String[] args) {
        HttpNIOServer server = new HttpNIOServer();
        server.start();
        System.exit(0);
    }

    HttpNIOServer(){
        try {
            es = Executors.newFixedThreadPool(5);
            serverSocketChannel = ServerSocketChannel.open();
            serverSocketChannel.configureBlocking(false);
            serverSocket = serverSocketChannel.socket();
            serverSocket.bind(new InetSocketAddress(SERVER_PORT));

            selector = Selector.open();
            serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);
            System.out.println("server init...");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void start(){
        try {
            while (!shutdown){
                selector.select();
                Set<SelectionKey> selectionKeySet = selector.selectedKeys();
                Iterator<SelectionKey> it = selectionKeySet.iterator();
                while (it.hasNext()){
                    SelectionKey selectionKey = it.next();
                    it.remove();
                    handleRequest(selectionKey);
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void handleRequest(SelectionKey selectionKey){
        ServerSocketChannel ssc = null;
        SocketChannel ss = null;
        try {
            if(selectionKey.isAcceptable()){
                ssc = (ServerSocketChannel) selectionKey.channel();
                ss = ssc.accept();

                ss.configureBlocking(false);
                ss.register(selector, SelectionKey.OP_READ);
            }else if(selectionKey.isReadable()){
                ss = (SocketChannel) selectionKey.channel();
                ByteBuffer byteBuffer = ByteBuffer.allocate(2048);
                StringBuffer sb = new StringBuffer();
                while (ss.read(byteBuffer) > 0){
                    byteBuffer.flip();
                    int lgn = byteBuffer.limit();
                    for (int i = 0; i < lgn; i++) {
                        sb.append((char)byteBuffer.get(i));
                    }
                    byteBuffer.clear();
                }
                if(sb.length() > 0) {
                    request = new Request();
                    request.takeUri(sb);
                    ss.register(selector, SelectionKey.OP_WRITE);
                }
            }else if(selectionKey.isWritable()){
                ss = (SocketChannel) selectionKey.channel();
                ByteBuffer rb = ByteBuffer.allocate(2048);
                Response response = new Response(ss);
                response.setRequest(request);
                response.responseNIO();
                ss.register(selector, SelectionKey.OP_READ);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}