Java实现http服务器（一）

基于Java实现Http服务器有多种多样的方法

一种轻量级的方式是使用JDK内置的com.sun.net.httpserver包下和sun.net.httpserver包下类提供的方法构建，该方法轻便快捷。

import java.io.IOException;
import java.net.InetSocketAddress;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

import com.sun.net.httpserver.HttpServer;

/**
* @author 作者 E-mail:
* @version 创建时间：2015-10-24 下午04:51:40 类说明
*/
public class HttpServerManager
{
private final  static HttpServerManager instance = new HttpServerManager();

private HttpServer httpServer = null;

private ExecutorService executor = null;

private HttpServerManager()
{

}

public final static HttpServerManager getInstance()
{
return instance;
}

public final void init() throws IOException
{
this.executor = Executors.newCachedThreadPool();
final InetSocketAddress sa = new InetSocketAddress("0.0.0.0", 8080);
this.httpServer = HttpServer.create(sa, 0);
this.httpServer.setExecutor(this.executor);
this.httpServer.createContext("/", new HttpServerHandler());
this.httpServer.start();
}

public final void exit()
{
this.executor.shutdown();
this.httpServer.stop(0);
}
}

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.URI;

import com.sun.net.httpserver.Headers;
import com.sun.net.httpserver.HttpExchange;
import com.sun.net.httpserver.HttpHandler;
import com.sun.net.ssl.HttpsURLConnection;

/**
* @author 作者 E-mail:
* @version 创建时间：2015-10-24 下午05:02:25 类说明
*/
public class HttpServerHandler implements HttpHandler
{

public void onError(HttpExchange exchange) throws IOException
{
exchange.sendResponseHeaders(HttpsURLConnection.HTTP_BAD_REQUEST,0);
exchange.getResponseBody().close();
}

public static String getQueryString(HttpExchange exchange) throws IOException
{

if (exchange.getRequestMethod().equalsIgnoreCase("GET"))
{
return exchange.getRequestURI().getQuery();
}

String requestBodyString = getRequestBodyString(exchange);

if (requestBodyString.length() == 0)
{
return exchange.getRequestURI().getQuery();
}
return requestBodyString;
}

public static String getRequestBodyString(HttpExchange exchange) throws IOException
{
BufferedReader br = new BufferedReader(new InputStreamReader(exchange.getRequestBody(), "UTF-8"));
StringBuilder builder = new StringBuilder();
String line = null;
while ((line = br.readLine()) != null)
{
builder.append(line);
}

return builder.toString();
}

@SuppressWarnings("deprecation")
@Override
public void handle(HttpExchange exchange) throws IOException
{
OutputStream os = null;
final URI uri = exchange.getRequestURI();
//http://127.0.0.1:8080/cmd/helloWorld
final String path = uri.getPath();
final String query = getQueryString(exchange);
final Headers responseHeaders = exchange.getResponseHeaders();
// 返回结果
final byte[] result = new byte[] { ' ', ' ' };

responseHeaders.set("Content-Type", "text/plain");
responseHeaders.set("Content-length", String.valueOf(result.length));

exchange.sendResponseHeaders(HttpsURLConnection.HTTP_OK, 0);
os = exchange.getResponseBody();
os.write(result);

os.close();
}
}

　　

再举一个使用jdk自带httpserver组件的例子：

import java.io.IOException;
import java.io.OutputStream;
import java.net.InetSocketAddress;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import java.util.concurrent.Executors;

import com.sun.net.httpserver.Headers;
import com.sun.net.httpserver.HttpExchange;
import com.sun.net.httpserver.HttpHandler;
import com.sun.net.httpserver.HttpServer;
//在eclipse中会出现Access restriction: The type Headers is not accessible due to restriction on required library
//解决办法：把Windows-Preferences-Java-Complicer- Errors/Warnings里面的Deprecated and restricted API中的Forbidden references(access rules)选为Warning就可以编译通过。
/**
* 使用jdk自带sun httpserver组件构建Http服务器，
* JDK自带的HttpServer是一个非常轻量级的Http服务端框架，但是它非常灵活，易于扩展，
* @author Administrator
*
*/
public class HttpServerDemo {
public static void main(String[] args) throws IOException {
InetSocketAddress addr = new InetSocketAddress(8080);
HttpServer server = HttpServer.create(addr, 0);

server.createContext("/", new MyHandler());
server.setExecutor(Executors.newCachedThreadPool());
server.start();
System.out.println("Server is listening on port 8080");
}
}

class MyHandler implements HttpHandler {

public void handle(HttpExchange exchange) throws IOException {

String requestMethod = exchange.getRequestMethod();
System.out.println("处理新请求:"+requestMethod);
if (requestMethod.equalsIgnoreCase("GET")) {
Headers responseHeaders = exchange.getResponseHeaders();
responseHeaders.set("Content-Type", "text/plain");
exchange.sendResponseHeaders(200, 0);

OutputStream responseBody = exchange.getResponseBody();
Headers requestHeaders = exchange.getRequestHeaders();
Set<String> keySet = requestHeaders.keySet();
Iterator<String> iter = keySet.iterator();
while (iter.hasNext()) {
String key = iter.next();
List values = requestHeaders.get(key);
String s = key + " = " + values.toString() + "\n";
responseBody.write(s.getBytes());
}
responseBody.close();
}
}
}