Merge pull request #39 from dongyuanlongwang/master

第三周的作业终于完成了

group03/1360464792/src/main/java/rui/study/coding2017/jobs3/download/DownloadThread.java

@@ -3,19 +3,35 @@
 
 import rui.study.coding2017.jobs3.download.api.Connection;
 
+import java.io.IOException;
+import java.io.RandomAccessFile;
+
+import static rui.study.coding2017.jobs3.download.FileDownloader.getFilePath;
+
 public class DownloadThread extends Thread{
 
 	Connection conn;
 	int startPos;
 	int endPos;
 
 	public DownloadThread(Connection conn, int startPos, int endPos){
-
-		this.conn = conn;		
+		this.conn = conn;
 		this.startPos = startPos;
 		this.endPos = endPos;
 	}
-	public void run(){	
-
+	@Override
+	public void run(){
+		try {
+			byte[] bytes=conn.read(startPos,endPos);
+			RandomAccessFile randomAccessFile=new RandomAccessFile(getFilePath(),"rw");
+            randomAccessFile.seek(startPos);
+            randomAccessFile.write(bytes);
+            randomAccessFile.close();
+		} catch (IOException e) {
+			e.printStackTrace();
+		}finally {
+			conn.close();
+		}
+
 	}
 }

group03/1360464792/src/main/java/rui/study/coding2017/jobs3/download/FileDownloader.java

@@ -6,68 +6,121 @@
 import rui.study.coding2017.jobs3.download.api.ConnectionManager;
 import rui.study.coding2017.jobs3.download.api.DownloadListener;
 
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+import java.util.ArrayList;
+import java.util.List;
+
 public class FileDownloader {
+
+	public static int threadNum=5;
 
 	String url;
 
 	DownloadListener listener;
 
 	ConnectionManager cm;
-
+
+	private static String filePath;
+
+    static String path="D:\\360downloads";
+
+    File pathFile;
+
+	public static String getFilePath() {
+		return filePath;
+	}
 
 	public FileDownloader(String _url) {
 		this.url = _url;
-
+		filePath=path+"/"+url.substring(url.lastIndexOf("/")+1);
+
+        pathFile=new File(path);
+        if(!pathFile.exists()||!pathFile.isDirectory()){
+            pathFile.mkdir();
+        }
 	}
-
+
+	public void setListener(DownloadListener listener) {
+		this.listener = listener;
+	}
+
+	public void setConnectionManager(ConnectionManager ucm){
+		this.cm = ucm;
+	}
+
 	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listener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;
+        Connection conn = null;
 		try {
-
 			conn = cm.open(this.url);
-
-			int length = conn.getContentLength();	
-			
-			new DownloadThread(conn,0,length-1).start();
-			
+			int length = conn.getContentLength();
+            setRandomAccessFile(length);
+            List<DownloadThread> list = getDownloadThreads(conn, length);
+            waitForDownLoad(list);
+            listener.notifyFinished();
 		} catch (ConnectionException e) {
 			e.printStackTrace();
-		}finally{
+		} catch (IOException 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;
-	}
-
+    /**
+     * 配置 随机访问文件
+     * 预分配文件所占的磁盘空间，磁盘中会创建一个指定大小的文件；
+     * @param length
+     * @throws IOException
+     */
+    private void setRandomAccessFile(int length) throws IOException {
+        try {
+            RandomAccessFile randomAccessFile=new RandomAccessFile(filePath,"rw");
+            randomAccessFile.setLength(length);
+            randomAccessFile.close();
+        } catch (FileNotFoundException e) {
+            e.printStackTrace();
+        }
+    }
+
+    /**
+     * 获得下载线程，为下一步阻塞做准备
+     * @param conn 连接
+     * @param length 长度
+     * @return
+     */
+    private List<DownloadThread> getDownloadThreads(Connection conn, int length) {
+        int startPos;
+        int endPos;
+        List<DownloadThread> list=new ArrayList<DownloadThread>();
+        for (int i = 0; i < threadNum; i++) {
+            //从0开始
+            startPos=i*(length/threadNum);
+            //从length/threadNum开始，最后为所有长度
+            endPos=(i==threadNum-1)?length-1:(i+1)*(length/threadNum);
+
+            DownloadThread downloadThread=new DownloadThread(conn,startPos,endPos);
+            downloadThread.start();
+            list.add(downloadThread);
+        }
+        return list;
+    }
+
+    /**
+     * 阻塞线程列表，等待线程列表全部执行完成
+     * @param list 线程列表
+     */
+    private void waitForDownLoad(List<DownloadThread> list) {
+        for (DownloadThread aList : list) {
+            try {
+                aList.join();
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        }
+    }
 }

group03/1360464792/src/main/java/rui/study/coding2017/jobs3/download/api/ConnectionManager.java

@@ -1,10 +1,13 @@
 package rui.study.coding2017.jobs3.download.api;
 
+import java.io.IOException;
+import java.net.MalformedURLException;
+
 public interface ConnectionManager {
 	/**
 	 * 给定一个url , 打开一个连接
 	 * @param url
 	 * @return
 	 */
-	public Connection open(String url) throws ConnectionException;	
+	public Connection open(String url) throws ConnectionException, IOException;
 }

group03/1360464792/src/main/java/rui/study/coding2017/jobs3/download/impl/ConnectionImpl.java

@@ -3,26 +3,55 @@
 
 import rui.study.coding2017.jobs3.download.api.Connection;
 
-import java.io.IOException;
+import java.io.*;
+import java.net.HttpURLConnection;
+import java.net.URL;
 
 public class ConnectionImpl implements Connection {
+    private static int byteSize = 8 * 1024;
+
+    private int contentLength;
+
+
+    private URL url;
+
+    public ConnectionImpl(URL url) throws IOException {
+        this.url = url;
+        HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
+        contentLength = httpURLConnection.getContentLength();
+        httpURLConnection.disconnect();
+    }
+
+    @Override
+    public byte[] read(int startPos, int endPos) throws IOException {
+        BufferedInputStream bufferedInputStream;
+
+        ByteArrayOutputStream outputStream;
+
+        HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
+        httpURLConnection.setRequestProperty("Range", "bytes=" + startPos + "-" + endPos);
+        bufferedInputStream = new BufferedInputStream(httpURLConnection.getInputStream());
+        outputStream = new ByteArrayOutputStream();
+        int temp;
+        byte[] bytes = new byte[byteSize];
+        while ((temp = bufferedInputStream.read(bytes)) != -1) {
+            outputStream.write(bytes, 0, temp);
+        }
+        bufferedInputStream.close();
+        outputStream.flush();
+        outputStream.close();
+        httpURLConnection.disconnect();
+        return outputStream.toByteArray();
+    }
+
+    @Override
+    public int getContentLength() {
+        return contentLength;
+    }
+
+    @Override
+    public void close() {
+    }
 
-	@Override
-	public byte[] read(int startPos, int endPos) throws IOException {
-
-		return null;
-	}
-
-	@Override
-	public int getContentLength() {
-
-		return 0;
-	}
-
-	@Override
-	public void close() {
-
-
-	}
 
 }

group03/1360464792/src/main/java/rui/study/coding2017/jobs3/download/impl/ConnectionManagerImpl.java

@@ -5,12 +5,14 @@
 import rui.study.coding2017.jobs3.download.api.ConnectionException;
 import rui.study.coding2017.jobs3.download.api.ConnectionManager;
 
+import java.io.IOException;
+import java.net.URL;
+
 public class ConnectionManagerImpl implements ConnectionManager {
 
 	@Override
-	public Connection open(String url) throws ConnectionException {
-
-		return null;
+	public Connection open(String url) throws ConnectionException, IOException {
+		return new ConnectionImpl(new URL(url));
 	}
 
 }

group03/1360464792/src/test/java/rui/study/coding2017/jobs3/FileDownloaderTest.java → group03/1360464792/src/test/java/rui/study/coding2017/jobs3/download/FileDownloaderTest.java

@@ -1,4 +1,4 @@
-package rui.study.coding2017.jobs3;
+package rui.study.coding2017.jobs3.download;
 
 import org.junit.After;
 import org.junit.Before;
@@ -22,8 +22,8 @@ public void tearDown() throws Exception {
 	@Test
 	public void testDownload() {
 
-		String url = "http://localhost:8080/test.jpg";
-		
+		String url = "http://sw.bos.baidu.com/sw-search-sp/software/952c9d6e73f50/QQ_8.9.20029.0_setup.exe";
+
 		FileDownloader downloader = new FileDownloader(url);
 
 
@@ -35,7 +35,6 @@ public void testDownload() {
 			public void notifyFinished() {
 				downloadFinished = true;
 			}
-
 		});
 
 
@@ -52,9 +51,6 @@ public void notifyFinished() {
 			}
 		}
 		System.out.println("下载完成！");
-
-
-
 	}
 
 }

group03/1360464792/src/test/java/rui/study/coding2017/jobs3/download/impl/ConnectionImplTest.java

@@ -0,0 +1,39 @@
+package rui.study.coding2017.jobs3.download.impl;
+
+import org.junit.Test;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.net.URL;
+
+import static org.junit.Assert.*;
+
+/**
+ * 测试链接实现
+ * Created by 赵睿 on 2017/3/15.
+ */
+public class ConnectionImplTest {
+    private String url="http://sw.bos.baidu.com/sw-search-sp/software/952c9d6e73f50/QQ_8.9.20029.0_setup.exe";
+
+    private ConnectionImpl connection=new ConnectionImpl(new URL(url));
+
+    public ConnectionImplTest() throws IOException {
+    }
+
+    @Test
+    public void read() throws Exception {
+        byte[] bs=connection.read(0,connection.getContentLength());
+        System.out.println(bs.length);
+        FileOutputStream fileOutputStream=new FileOutputStream(new File("D://eee.exe"));
+        fileOutputStream.write(bs);
+        fileOutputStream.flush();
+        fileOutputStream.close();
+    }
+
+    @Test
+    public void getContentLength() throws Exception {
+        System.out.println(connection.getContentLength());
+    }
+
+}