Java tutorial
package smn.learn.jcassandra; /* * ==================================================================== * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ import java.io.File; import java.io.IOException; import java.io.InterruptedIOException; import java.net.ServerSocket; import java.net.Socket; import java.net.URLDecoder; import java.nio.charset.Charset; import java.util.Locale; import org.apache.http.ConnectionClosedException; import org.apache.http.HttpEntity; import org.apache.http.HttpEntityEnclosingRequest; import org.apache.http.HttpException; import org.apache.http.HttpRequest; import org.apache.http.HttpResponse; import org.apache.http.HttpResponseInterceptor; import org.apache.http.HttpServerConnection; import org.apache.http.HttpStatus; import org.apache.http.MethodNotSupportedException; import org.apache.http.entity.ContentType; import org.apache.http.entity.FileEntity; import org.apache.http.entity.StringEntity; import org.apache.http.impl.DefaultConnectionReuseStrategy; import org.apache.http.impl.DefaultHttpResponseFactory; import org.apache.http.impl.DefaultHttpServerConnection; import org.apache.http.params.CoreConnectionPNames; import org.apache.http.params.HttpParams; import org.apache.http.params.CoreProtocolPNames; import org.apache.http.params.SyncBasicHttpParams; import org.apache.http.protocol.HttpContext; import org.apache.http.protocol.BasicHttpContext; import org.apache.http.protocol.HttpProcessor; import org.apache.http.protocol.HttpRequestHandler; import org.apache.http.protocol.HttpRequestHandlerRegistry; import org.apache.http.protocol.HttpService; import org.apache.http.protocol.ImmutableHttpProcessor; import org.apache.http.protocol.ResponseConnControl; import org.apache.http.protocol.ResponseContent; import org.apache.http.protocol.ResponseDate; import org.apache.http.protocol.ResponseServer; import org.apache.http.util.EntityUtils; /** * Basic, yet fully functional and spec compliant, HTTP/1.1 file server. * <p> * Please note the purpose of this application is demonstrate the usage of HttpCore APIs. * It is NOT intended to demonstrate the most efficient way of building an HTTP file server. * * */ public class TsubscribeServer { public static void serve(String[] args) throws Exception { if (args.length < 1) { System.err.println("Please specify document root directory"); System.exit(1); } Thread t = new RequestListenerThread(8080, args[0]); t.setDaemon(false); t.start(); } static class HttpFileHandler implements HttpRequestHandler { private final String docRoot; public HttpFileHandler(final String docRoot) { super(); this.docRoot = docRoot; } public void handle(final HttpRequest request, final HttpResponse response, final HttpContext context) throws HttpException, IOException { String method = request.getRequestLine().getMethod().toUpperCase(Locale.ENGLISH); if (!method.equals("GET") && !method.equals("HEAD") && !method.equals("POST")) { throw new MethodNotSupportedException(method + " method not supported"); } String target = request.getRequestLine().getUri(); if (request instanceof HttpEntityEnclosingRequest) { HttpEntity entity = ((HttpEntityEnclosingRequest) request).getEntity(); byte[] entityContent = EntityUtils.toByteArray(entity); System.out.println("Incoming entity content (bytes): " + entityContent.length); } final File file = new File(this.docRoot, URLDecoder.decode(target, "UTF-8")); if (!file.exists()) { response.setStatusCode(HttpStatus.SC_NOT_FOUND); StringEntity entity = new StringEntity( "<html><body><h1>File" + file.getPath() + " not found</h1></body></html>", ContentType.create("text/html", "UTF-8")); response.setEntity(entity); System.out.println("File " + file.getPath() + " not found"); } else if (!file.canRead() || file.isDirectory()) { response.setStatusCode(HttpStatus.SC_FORBIDDEN); StringEntity entity = new StringEntity("<html><body><h1>Access denied</h1></body></html>", ContentType.create("text/html", "UTF-8")); response.setEntity(entity); System.out.println("Cannot read file " + file.getPath()); } else { response.setStatusCode(HttpStatus.SC_OK); FileEntity body = new FileEntity(file, ContentType.create("text/html", (Charset) null)); response.setEntity(body); System.out.println("Serving file " + file.getPath()); } } } static class RequestListenerThread extends Thread { private final ServerSocket serversocket; private final HttpParams params; private final HttpService httpService; public RequestListenerThread(int port, final String docroot) throws IOException { this.serversocket = new ServerSocket(port); this.params = new SyncBasicHttpParams(); this.params.setIntParameter(CoreConnectionPNames.SO_TIMEOUT, 5000) .setIntParameter(CoreConnectionPNames.SOCKET_BUFFER_SIZE, 8 * 1024) .setBooleanParameter(CoreConnectionPNames.STALE_CONNECTION_CHECK, false) .setBooleanParameter(CoreConnectionPNames.TCP_NODELAY, true) .setParameter(CoreProtocolPNames.ORIGIN_SERVER, "HttpComponents/1.1"); // Set up the HTTP protocol processor HttpProcessor httpproc = new ImmutableHttpProcessor(new HttpResponseInterceptor[] { new ResponseDate(), new ResponseServer(), new ResponseContent(), new ResponseConnControl() }); // Set up request handlers HttpRequestHandlerRegistry reqistry = new HttpRequestHandlerRegistry(); reqistry.register("*", new HttpFileHandler(docroot)); // Set up the HTTP service this.httpService = new HttpService(httpproc, new DefaultConnectionReuseStrategy(), new DefaultHttpResponseFactory(), reqistry, this.params); } @Override public void run() { System.out.println("Listening on port " + this.serversocket.getLocalPort()); while (!Thread.interrupted()) { try { // Set up HTTP connection Socket socket = this.serversocket.accept(); DefaultHttpServerConnection conn = new DefaultHttpServerConnection(); System.out.println("Incoming connection from " + socket.getInetAddress()); conn.bind(socket, this.params); // Start worker thread Thread t = new WorkerThread(this.httpService, conn); t.setDaemon(true); t.start(); } catch (InterruptedIOException ex) { break; } catch (IOException e) { System.err.println("I/O error initialising connection thread: " + e.getMessage()); break; } } } } static class WorkerThread extends Thread { private final HttpService httpservice; private final HttpServerConnection conn; public WorkerThread(final HttpService httpservice, final HttpServerConnection conn) { super(); this.httpservice = httpservice; this.conn = conn; } @Override public void run() { System.out.println("New connection thread"); HttpContext context = new BasicHttpContext(null); try { while (!Thread.interrupted() && this.conn.isOpen()) { this.httpservice.handleRequest(this.conn, context); } } catch (ConnectionClosedException ex) { System.err.println("Client closed connection"); } catch (IOException ex) { System.err.println("I/O error: " + ex.getMessage()); } catch (HttpException ex) { System.err.println("Unrecoverable HTTP protocol violation: " + ex.getMessage()); } finally { try { this.conn.shutdown(); } catch (IOException ignore) { } } } } }