Merge pull request #105 from ChristopherYue/master

group 10

group10/3314793852/.classpath

@@ -2,5 +2,6 @@
 <classpath>
 	<classpathentry kind="src" path="src"/>
 	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.junit.JUNIT_CONTAINER/4"/>
 	<classpathentry kind="output" path="bin"/>
 </classpath>

group10/3314793852/WEB-INF/web.xml

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="ISO-8859-1"?>
+<!--
+ 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.
+-->
+
+<web-app xmlns="http://java.sun.com/xml/ns/javaee"
+   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+   xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
+   version="2.5">
+
+  <display-name>Welcome to Tomcat</display-name>
+  <description>
+     Welcome to Tomcat
+  </description>
+
+</web-app>

group10/3314793852/src/com/coderising/download/DownloadThread.java

@@ -0,0 +1,50 @@
+	/*
+	 *  打开输入流下载，对应分配的资源。
+	 */
+	package com.coderising.download;
+
+	import java.io.IOException;
+	import java.io.RandomAccessFile;
+
+	import com.coderising.download.api.Connection;
+
+	public class DownloadThread extends Thread{
+
+		Connection conn;				//用来打开下载资源的对用的输入流。
+		RandomAccessFile currentPart;	//当前线程下载到本地的位置
+		int startPos;					//下载起始位置。
+		int endPos;						//下载结束位置。
+		int hasRead=0;					//已经下载的长度。
+
+		//构造器。
+		public DownloadThread( Connection conn, int startPos, int endPos,RandomAccessFile currentPart){
+
+			this.conn = conn;	
+			this.currentPart=currentPart;
+			this.startPos = startPos;
+			this.endPos = endPos;
+		}
+
+
+		/*在该方法中要将数据从byte数组写入到文件中.
+		 * 要先把数据写入byte数组中，再从数组中把数据写入文件中。
+		 */
+		public void run(){	
+
+			try {
+				synchronized(this){
+					byte[] buff=new byte[endPos-startPos+1];
+					buff=conn.read(startPos, endPos);
+					//将字节数组中的数据读入指定文件中。
+					for(int i=0;i<buff.length;i++){
+						currentPart.write(buff[i]);
+						hasRead++;
+					}
+					//System.out.println("Over");
+					currentPart.close();
+				}
+			} catch (Exception e) {
+				e.printStackTrace();
+			}
+		}
+	}

group10/3314793852/src/com/coderising/download/FileDownloader.java

@@ -0,0 +1,116 @@
+
+	package com.coderising.download;
+
+	import java.io.RandomAccessFile;
+
+	import com.coderising.download.api.Connection;
+	import com.coderising.download.api.ConnectionException;
+	import com.coderising.download.api.ConnectionManager;
+	import com.coderising.download.api.DownloadListener;
+	import com.coderising.download.impl.DownloadListenerImpl;
+
+
+	public class FileDownloader {
+
+		String url;						//URL地址
+		DownloadListener listener;		//下载完成通知
+		ConnectionManager cm;			//打开URL链接
+		String targetFile="E:/moon.png";				//指定所下载文件的保存位置
+
+		public FileDownloader(String _url) {
+			this.url = _url;
+		}
+
+		public void execute(){
+			// 在这里实现你的代码， 注意： 需要用多线程实现下载
+			// 这个类依赖于其他几个接口, 你需要写这几个接口的实现代码
+			// (1) ConnectionManager , 可以打开一个连接，通过Connection可以读取其中的一段（用startPos, endPos来指定）
+			// (2) DownloadListener, 由于是多线程下载， 调用这个类的客户端不知道什么时候结束，所以你需要实现当所有
+			//     线程都执行完以后， 调用DownloadListener的notifiedFinished方法， 这样客户端就能收到通知。
+			// 具体的实现思路：
+			// 1. 需要调用ConnectionManager的open方法打开连接， 然后通过Connection.getContentLength方法获得文件的长度
+			// 2. 至少启动3个线程下载，  注意每个线程需要先调用ConnectionManager的open方法
+			// 然后调用read方法， read方法中有读取文件的开始位置和结束位置的参数， 返回值是byte[]数组
+			// 3. 把byte数组写入到文件中
+			// 4. 所有的线程都下载完成以后， 需要调用listener的notifiedFinished方法
+
+			// 下面的代码是示例代码， 也就是说只有一个线程， 你需要改造成多线程的。
+			Connection conn = null;
+			try {
+
+				conn = cm.open(this.url);						//ConnectionManager的对象的open方法返回一个Connection对象
+				int length = conn.getContentLength();			//获得文件的总长度。
+				//System.out.println(length);
+				//创建一个文件，用来保存下载的资源。
+				RandomAccessFile file = new RandomAccessFile(targetFile, "rw");
+				//设置本地文件的大小。
+				file.setLength(length);
+
+				file.close();
+
+
+				int numberOfThread=4;							//线程的个数，自定义，当前定为4.
+
+				int eachLength=length/4+1;						//每个线程的下载的长度。
+				RandomAccessFile[] currentPart=new RandomAccessFile[4];
+				DownloadThread[] thread=new DownloadThread[4];
+				for(int i=0;i<numberOfThread-1;i++){				//确定子线程的开始和结尾点，并启动子线程。
+					currentPart[i]= new RandomAccessFile(targetFile, "rw");
+					currentPart[i].seek(0+eachLength*i);
+					thread[i]=new DownloadThread(conn,0+eachLength*i,eachLength+eachLength*i-1,currentPart[i]);
+					thread[i].start();	//启动线程。
+					//System.out.println(i);
+				}
+				currentPart[3]= new RandomAccessFile(targetFile, "rw");
+				currentPart[3].seek(eachLength*3);
+				thread[3]=new DownloadThread(conn,eachLength*3,length-1,currentPart[3]);
+				thread[3].start();		//最后一个线程
+
+				//统计多条线程已经下载的总大小。
+
+
+
+				int sumSize=0;
+				//检测是否下载完毕
+				while(true){
+
+					for(int j=0;j<numberOfThread;j++){
+						sumSize+=thread[j].hasRead;
+					}
+					//System.out.println("sumSize"+sumSize);
+					if(sumSize==length){
+						listener.notifyFinished();
+						//System.out.println("完成");
+						System.out.println("下载完成！");
+						break;
+					}
+					sumSize=0;
+//					Thread.sleep(10000);
+				}
+
+			} catch (Exception e) {			
+				e.printStackTrace();
+			}finally{
+//				if(conn != null){
+//					conn.close();
+//				}
+			}
+		}
+
+
+
+		public void setListener(DownloadListener listener) {
+			this.listener = listener;
+		}
+
+
+
+		public void setConnectionManager(ConnectionManager ucm){
+			this.cm = ucm;
+		}
+
+		public DownloadListener getListener(){
+			return this.listener;
+		}
+
+	}

group10/3314793852/src/com/coderising/download/FileDownloaderTest.java

@@ -0,0 +1,80 @@
+
+	package com.coderising.download;
+
+	import org.junit.After;
+	import org.junit.Before;
+	import org.junit.Test;
+
+	import com.coderising.download.api.ConnectionManager;
+	import com.coderising.download.api.DownloadListener;
+	import com.coderising.download.impl.ConnectionManagerImpl;
+	import com.coderising.download.impl.DownloadListenerImpl;
+
+	public class FileDownloaderTest {
+		boolean downloadFinished = false;
+		@Before
+		public void setUp() throws Exception {
+		}
+
+		@After
+		public void tearDown() throws Exception {
+		}
+
+		@Test
+		public void testDownload() {
+
+			String url = "http://localhost:8080/demo/moon.png";
+
+			FileDownloader downloader = new FileDownloader(url);
+
+
+			ConnectionManager cm = new ConnectionManagerImpl();
+			downloader.setConnectionManager(cm);
+
+
+			downloader.setListener(new DownloadListener() {
+				@Override
+				public void notifyFinished() {
+					downloadFinished = true;
+				}
+
+			});
+
+			 new Thread(new Runnable() {
+		            @Override
+		            public void run() {
+		                while(!downloadFinished){
+		                    System.out.println("还没有下载完成，休眠五秒");
+		                    try {
+		                        Thread.sleep(5000);
+		                    } catch (InterruptedException e) {
+		                        e.printStackTrace();
+		                    }
+		                }
+		               System.out.println("下载完成！");
+		            }
+		        }).start();
+
+			downloader.execute();
+
+
+
+
+			// 等待多线程下载程序执行完毕
+
+//				while (!downloadFinished) {
+//					try {
+//						System.out.println("还没有下载完成，休眠五秒");
+//						//休眠5秒
+//						Thread.sleep(5000);
+//					} catch (InterruptedException e) {				
+//						e.printStackTrace();
+//					}
+//				}
+//				System.out.println("下载完成！");
+
+
+
+		}
+
+	}

group10/3314793852/src/com/coderising/download/api/Connection.java

@@ -0,0 +1,25 @@
+package com.coderising.download.api;
+
+import java.io.IOException;
+
+public interface Connection {
+	/**
+	 * 给定开始和结束位置， 读取数据， 返回值是字节数组
+	 * @param startPos 开始位置， 从0开始
+	 * @param endPos 结束位置
+	 * @return
+	 */
+
+
+	public byte[] read(int startPos,int endPos) throws IOException;
+	/**
+	 * 得到数据内容的长度
+	 * @return
+	 */
+	public int getContentLength();
+
+	/**
+	 * 关闭连接
+	 */
+	public void close();
+}

group10/3314793852/src/com/coderising/download/api/ConnectionException.java

@@ -0,0 +1,5 @@
+package com.coderising.download.api;
+
+public class ConnectionException extends Exception {
+
+}

group10/3314793852/src/com/coderising/download/api/ConnectionManager.java

@@ -0,0 +1,10 @@
+package com.coderising.download.api;
+
+public interface ConnectionManager {
+	/**
+	 * 给定一个url , 打开一个连接
+	 * @param url
+	 * @return
+	 */
+	public Connection open(String url) throws ConnectionException;	
+}

group10/3314793852/src/com/coderising/download/api/DownloadListener.java

@@ -0,0 +1,5 @@
+package com.coderising.download.api;
+
+public interface DownloadListener {
+	public void notifyFinished();
+}