Merge pull request #11 from vxzh/master

L3

group13/2729382520/L3/src/io/github/vxzh/download/DownloadThread.java

@@ -0,0 +1,40 @@
+package io.github.vxzh.download;
+
+import io.github.vxzh.download.api.Connection;
+
+import java.io.RandomAccessFile;
+import java.util.concurrent.CyclicBarrier;
+
+public class DownloadThread extends Thread {
+
+    private Connection conn;
+    private int startPos;
+    private int endPos;
+    private CyclicBarrier barrier;
+
+    public DownloadThread(Connection conn, int startPos, int endPos, CyclicBarrier barrier) {
+
+        this.conn = conn;
+        this.startPos = startPos;
+        this.endPos = endPos;
+        this.barrier = barrier;
+    }
+
+    public void run() {
+
+        try {
+
+            byte[] buffer = conn.read(startPos, endPos);
+            RandomAccessFile raf = new RandomAccessFile("/Users/xuxiaoqing/Documents/demo.jpg", "rw");
+            raf.seek(startPos);
+            raf.write(buffer, 0, buffer.length);
+            //raf.write(buffer);
+            raf.close();
+            barrier.await();
+
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+
+    }
+}

group13/2729382520/L3/src/io/github/vxzh/download/FileDownloader.java

@@ -0,0 +1,76 @@
+package io.github.vxzh.download;
+
+import io.github.vxzh.download.api.Connection;
+import io.github.vxzh.download.api.ConnectionManager;
+import io.github.vxzh.download.api.DownloadListener;
+
+import java.util.concurrent.CyclicBarrier;
+
+public class FileDownloader {
+
+    private String path;
+
+    private DownloadListener listener;
+
+    private ConnectionManager cm;
+
+    private static final int THREAD_NUM = 3;
+
+    public FileDownloader(String path) {
+        this.path = path;
+
+    }
+
+    public void execute() {
+
+        CyclicBarrier barrier = new CyclicBarrier(THREAD_NUM, new Runnable() {
+            @Override
+            public void run() {
+                listener.notifyFinished();
+            }
+        });
+
+        Connection conn = null;
+        try {
+
+            conn = cm.open(this.path);
+            //实际的文件长度
+            int length = conn.getContentLength();
+            //平均每一个线程下载的文件大小.
+            int blockSize = length / THREAD_NUM;
+            for (int threadId = 1; threadId <= THREAD_NUM; threadId++) {
+                int startIndex = (threadId - 1) * blockSize;
+                int endIndex = threadId * blockSize - 1;
+                //最后一个线程下载的长度
+                if (threadId == THREAD_NUM) {
+                    endIndex = length - 1;
+                }
+
+                System.out.println("线程：" + threadId + "下载:---" + startIndex + "--->" + endIndex);
+                new DownloadThread(conn, startIndex, endIndex, barrier).start();
+            }
+        } 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;
+    }
+
+}

group13/2729382520/L3/src/io/github/vxzh/download/FileDownloaderTest.java

@@ -0,0 +1,52 @@
+package io.github.vxzh.download;
+
+import io.github.vxzh.download.api.ConnectionManager;
+import io.github.vxzh.download.api.DownloadListener;
+import io.github.vxzh.download.impl.ConnectionManagerImpl;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+public class FileDownloaderTest {
+    private boolean downloadFinished = false;
+
+    @Before
+    public void setUp() throws Exception {
+    }
+
+    @After
+    public void tearDown() throws Exception {
+    }
+
+    @Test
+    public void testDownload() {
+
+        String url = "http://c.hiphotos.baidu.com/zhidao/pic/item/29381f30e924b8999bfaab046d061d950b7bf6cc.jpg";
+
+        FileDownloader downloader = new FileDownloader(url);
+        ConnectionManager cm = new ConnectionManagerImpl();
+        downloader.setConnectionManager(cm);
+
+        downloader.setListener(new DownloadListener() {
+            @Override
+            public void notifyFinished() {
+                downloadFinished = true;
+            }
+
+        });
+
+        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！");
+    }
+}