提交第3次作业及第4次作业框架

group06/263050006/src/main/java/com/github/chaoswang/learning/java/array/ArrayUtil.java

@@ -20,6 +20,10 @@ public class ArrayUtil {
 	 */
 	public static int[] reverseArray(int[] origin){
 		int length = origin.length;
+		if(origin == null || length == 0){
+			return null;
+		}
+
 		for(int i=0;i<length/2;i++){
 			int tmp = origin[i];
 			origin[i] = origin[length - 1 - i];
@@ -69,7 +73,7 @@ private static Integer[] convertToIntegerArray(int[] array){
 		return returnArray;
 	}
 
-	private static int[] returnByIntArray(Collection<Integer> collection){
+	public static int[] returnByIntArray(Collection<Integer> collection){
 		int[] returnArray = new int[collection.size()];
 		int i = 0;
 		for(Iterator<Integer> it = collection.iterator(); it.hasNext();){

group06/263050006/src/main/java/com/github/chaoswang/learning/java/downloader/DownloadThread.java

@@ -0,0 +1,49 @@
+package com.github.chaoswang.learning.java.downloader;
+
+import java.io.IOException;
+import java.io.RandomAccessFile;
+
+import com.github.chaoswang.learning.java.downloader.api.Connection;
+
+public class DownloadThread extends Thread{
+
+	private Connection conn;
+	private int startPos;
+	private int endPos;
+
+	public DownloadThread(Connection conn, int totalSection, int sectionIndex){
+		this.conn = conn;
+		int contentLength = conn.getContentLength();
+		initStartPosAndEndPos(contentLength, totalSection, sectionIndex);
+	}
+
+	private void initStartPosAndEndPos(int contentLength, int totalSection, int sectionIndex){
+		int sectionLength = contentLength / totalSection;  
+		startPos = (sectionIndex - 1) * sectionLength;
+        if(sectionIndex == totalSection){
+        	endPos = contentLength - 1;
+        }else{
+        	endPos = sectionIndex * sectionLength - 1;
+        }
+	}
+
+	public void run(){	
+		try {
+			writeByteArrayToFile(conn.read(startPos, endPos), "F:\\tmp\\6977.png");
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+	}
+
+	private void writeByteArrayToFile(byte[] buf, String destFilePath){
+		try {
+			// ����һ���ɶ���д����������ļ�
+			RandomAccessFile out = new RandomAccessFile(destFilePath, "rw");
+			out.seek(startPos);// ��ָ��λ�ÿ�ʼд
+			out.write(buf);
+	        out.close();// ���ﵽ��ر��ļ�
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+	}
+}

group06/263050006/src/main/java/com/github/chaoswang/learning/java/downloader/FileDownloader.java

@@ -0,0 +1,90 @@
+package com.github.chaoswang.learning.java.downloader;
+
+import java.util.ArrayList;
+import java.util.concurrent.TimeUnit;
+
+import com.github.chaoswang.learning.java.downloader.api.Connection;
+import com.github.chaoswang.learning.java.downloader.api.ConnectionException;
+import com.github.chaoswang.learning.java.downloader.api.ConnectionManager;
+import com.github.chaoswang.learning.java.downloader.api.DownloadListener;
+
+public class FileDownloader {
+	String url;
+	DownloadListener listener;
+	ConnectionManager cm;
+	int threadNum = 10;
+
+	public FileDownloader(String _url, int threadNum) {
+		this.url = _url;
+		this.threadNum = threadNum;
+	}
+
+	public void execute(){
+		// ������ʵ����Ĵ��룬 ע�⣺ ��Ҫ�ö��߳�ʵ������
+		// ��������������������ӿ�, ����Ҫд�⼸���ӿڵ�ʵ�ִ���
+		// (1) ConnectionManager , ���Դ�һ�����ӣ�ͨ��Connection���Զ�ȡ���е�һ�Σ���startPos, endPos��ָ����
+		// (2) DownloadListener, �����Ƕ��߳����أ� ���������Ŀͻ��˲�֪��ʲôʱ���������������Ҫʵ�ֵ�����
+		//     �̶߳�ִ�����Ժ� ����listener��notifiedFinished������ �����ͻ��˾����յ�֪ͨ��
+		// �����ʵ��˼·��
+		// 1. ��Ҫ����ConnectionManager��open���������ӣ� Ȼ��ͨ��Connection.getContentLength��������ļ��ij���
+		// 2. ��������3���߳����أ�  ע��ÿ���߳���Ҫ�ȵ���ConnectionManager��open����
+		// Ȼ�����read������ read�������ж�ȡ�ļ��Ŀ�ʼλ�úͽ���λ�õIJ����� ����ֵ��byte[]����
+		// 3. ��byte����д�뵽�ļ���
+		// 4. ���е��̶߳���������Ժ� ��Ҫ����listener��notifiedFinished����
+
+		// ����Ĵ�����ʾ�����룬 Ҳ����˵ֻ��һ���̣߳� ����Ҫ����ɶ��̵߳ġ�
+		// ���http://blog.csdn.net/yan8024/article/details/46474239
+
+		long startTime = System.currentTimeMillis();
+		//�ж������߳��Ƿ��������
+		ArrayList<Thread> list = new ArrayList<Thread>();
+
+		try{
+			for(int i=1; i<=threadNum; i++){
+				Connection conn = cm.open(url);
+				Thread dt = new DownloadThread(conn, threadNum, i);
+				dt.start();
+				list.add(dt);
+			}
+		}catch(ConnectionException e){
+			e.printStackTrace();
+			return;
+		}
+
+		while(true){
+			try {
+				TimeUnit.SECONDS.sleep(1);
+			} catch (InterruptedException e) {
+				e.printStackTrace();
+				break;
+			}
+			if(!isAllFinished(list)){
+				continue;
+			}
+			System.out.println("finished, cost time:" + (System.currentTimeMillis() - startTime));
+			listener.notifyFinished();
+			break;
+		}
+	}
+
+	private boolean isAllFinished(ArrayList<Thread> list){
+		for(Thread t : list){
+			if(t.getState() != Thread.State.TERMINATED){
+				return false;
+			}
+		}
+		return true;
+	}
+
+	public void setListener(DownloadListener listener) {
+		this.listener = listener;
+	}
+
+	public void setConnectionManager(ConnectionManager ucm){
+		this.cm = ucm;
+	}
+
+	public DownloadListener getListener(){
+		return this.listener;
+	}
+}

group06/263050006/src/main/java/com/github/chaoswang/learning/java/downloader/api/Connection.java

@@ -0,0 +1,23 @@
+package com.github.chaoswang.learning.java.downloader.api;
+
+import java.io.IOException;
+
+public interface Connection {
+	/**
+	 * ������ʼ�ͽ���λ�ã� ��ȡ���ݣ� ����ֵ���ֽ�����
+	 * @param startPos ��ʼλ�ã� ��0��ʼ
+	 * @param endPos �����
+	 * @return
+	 */
+	public byte[] read(int startPos,int endPos) throws IOException;
+	/**
+	 * �õ��������ݵij���
+	 * @return
+	 */
+	public int getContentLength();
+
+	/**
+	 * �ر�����
+	 */
+	public void close();
+}

group06/263050006/src/main/java/com/github/chaoswang/learning/java/downloader/api/ConnectionException.java

@@ -0,0 +1,10 @@
+package com.github.chaoswang.learning.java.downloader.api;
+
+public class ConnectionException extends Exception {
+	private static final long serialVersionUID = -6832188361613061488L;
+
+	public ConnectionException(String message){
+		super(message);
+	}
+
+}

group06/263050006/src/main/java/com/github/chaoswang/learning/java/downloader/api/ConnectionManager.java

@@ -0,0 +1,10 @@
+package com.github.chaoswang.learning.java.downloader.api;
+
+public interface ConnectionManager {
+	/**
+	 * ����һ��url , ��һ������
+	 * @param url
+	 * @return
+	 */
+	public Connection open(String url) throws ConnectionException;	
+}

group06/263050006/src/main/java/com/github/chaoswang/learning/java/downloader/api/DownloadListener.java

@@ -0,0 +1,5 @@
+package com.github.chaoswang.learning.java.downloader.api;
+
+public interface DownloadListener {
+	public void notifyFinished();
+}