diff --git a/group22/627559964/src/com/coderising/download/DownloadThread.java b/group22/627559964/src/com/coderising/download/DownloadThread.java
new file mode 100644
index 0000000000..5497305ea7
--- /dev/null
+++ b/group22/627559964/src/com/coderising/download/DownloadThread.java
@@ -0,0 +1,45 @@
+package com.coderising.download;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.RandomAccessFile;
+import java.util.concurrent.CyclicBarrier;
+
+import com.coderising.download.api.Connection;
+
+
+public class DownloadThread extends Thread {
+
+	Connection conn;
+	int startPos;
+	int endPos;
+	CyclicBarrier barrier;
+	String localFile;
+
+	public DownloadThread(Connection conn, int startPos, int endPos, CyclicBarrier barrier, String localFile) {
+		super();
+		this.conn = conn;
+		this.startPos = startPos;
+		this.endPos = endPos;
+		this.barrier = barrier;
+		this.localFile = localFile;
+	}
+
+	public void run() {
+		
+		try {	
+			
+			byte[] data = conn.read(startPos, endPos);		
+			RandomAccessFile file = new RandomAccessFile(localFile,"rw");
+			file.seek(startPos);	
+			file.write(data);
+			file.close();
+			conn.close();
+			barrier.await(); //等待别的线程完成
+			
+		} catch (Exception e) {			
+			e.printStackTrace();
+			
+		} 
+	}
+}
diff --git a/group22/627559964/src/com/coderising/download/FileDownloader.java b/group22/627559964/src/com/coderising/download/FileDownloader.java
new file mode 100644
index 0000000000..fa4375df7b
--- /dev/null
+++ b/group22/627559964/src/com/coderising/download/FileDownloader.java
@@ -0,0 +1,122 @@
+package com.coderising.download;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+import java.util.concurrent.CyclicBarrier;
+
+import com.coderising.download.api.Connection;
+import com.coderising.download.api.ConnectionException;
+import com.coderising.download.api.ConnectionManager;
+import com.coderising.download.api.DownloadListener;
+
+
+public class FileDownloader {
+	
+	private String url;
+	private DownloadListener listener;
+	private ConnectionManager cm;
+	private String localFile;
+	int threadNum = 3;
+	
+	public FileDownloader(String url, String localFile) {
+		super();
+		this.url = url;
+		this.localFile = localFile;
+	}
+
+	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。
+		
+		CyclicBarrier barrier = new CyclicBarrier(threadNum, new Runnable(){
+
+			@Override
+			public void run() {
+				listener.notifyFinished();
+			}
+			
+		});
+		
+		Connection conn = null;
+		try {
+			
+			conn = cm.open(this.url);
+			int length = conn.getContentLength();
+			int threadPart = length / threadNum + 1;
+			createPlaceHolderFile(this.localFile, length);
+			int[][] ranges = allocateDownloadRange(threadNum, length);
+			for (int i = 0; i < this.threadNum; i++) {
+				
+				DownloadThread thread = new DownloadThread(cm.open(url), ranges[i][0], ranges[i][1], barrier, localFile);
+				thread.start();
+				
+			}
+			
+		} catch (Exception e) {
+			e.printStackTrace();
+		}finally{
+			if(conn != null){
+				conn.close();
+			}
+		}
+		
+	}
+	
+	private void createPlaceHolderFile(String fileName, int contentLen) throws IOException{
+		
+		RandomAccessFile file = new RandomAccessFile(fileName,"rw");
+		
+		for(int i=0; i<contentLen ;i++){
+			file.write(0);
+		}
+		
+		file.close();
+	}
+	
+	private int[][] allocateDownloadRange(int threadNum, int contentLen){
+		int[][] ranges = new int[threadNum][2];
+		
+		int eachThreadSize = contentLen / threadNum;// 每个线程需要下载的文件大小
+		int left = contentLen % threadNum;// 剩下的归最后一个线程来处理
+		
+		for(int i=0;i<threadNum;i++){
+	
+			int startPos = i * eachThreadSize;
+			int endPos = (i + 1) * eachThreadSize - 1;
+			if ((i == (threadNum - 1))) {
+				endPos += left;
+			}
+			ranges[i][0] = startPos;
+			ranges[i][1] = endPos;
+			
+		}
+		
+		return ranges;
+	}
+	
+	public void setListener(DownloadListener listener) {
+		this.listener = listener;
+	}
+
+	public void setConnectionManager(ConnectionManager ucm){
+		this.cm = ucm;
+	}
+	
+	public DownloadListener getListener(){
+		return this.listener;
+	}
+	
+}
diff --git a/group22/627559964/src/com/coderising/download/FileDownloaderTest.java b/group22/627559964/src/com/coderising/download/FileDownloaderTest.java
new file mode 100644
index 0000000000..ddb4a1d271
--- /dev/null
+++ b/group22/627559964/src/com/coderising/download/FileDownloaderTest.java
@@ -0,0 +1,56 @@
+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;
+
+public class FileDownloaderTest {
+	boolean downloadFinished = false;
+	@Before
+	public void setUp() throws Exception {
+	}
+
+	@After
+	public void tearDown() throws Exception {
+	}
+
+	@Test
+	public void testDownload() {
+		
+		String url = "https://ss0.baidu.com/-Po3dSag_xI4khGko9WTAnF6hhy/super/crop=378,138,1512,942/sign=9cca06797b3e6709aa4f1fbf06f4a805/f9198618367adab471a1e11d8fd4b31c8701e47f.jpg";
+		
+		FileDownloader downloader = new FileDownloader(url, "C:/Users/Administrator/Desktop/1.jpg");
+	
+		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(100);
+			} catch (InterruptedException e) {				
+				e.printStackTrace();
+			}
+		}
+		System.out.println("下载完成！");
+
+	}
+
+}
diff --git a/group22/627559964/src/com/coderising/download/api/Connection.java b/group22/627559964/src/com/coderising/download/api/Connection.java
new file mode 100644
index 0000000000..a7b2decbeb
--- /dev/null
+++ b/group22/627559964/src/com/coderising/download/api/Connection.java
@@ -0,0 +1,25 @@
+package com.coderising.download.api;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+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();
+	
+}
diff --git a/group22/627559964/src/com/coderising/download/api/ConnectionException.java b/group22/627559964/src/com/coderising/download/api/ConnectionException.java
new file mode 100644
index 0000000000..d38efe82d5
--- /dev/null
+++ b/group22/627559964/src/com/coderising/download/api/ConnectionException.java
@@ -0,0 +1,10 @@
+package com.coderising.download.api;
+
+public class ConnectionException extends Exception {
+
+	/**
+	 * 
+	 */
+	private static final long serialVersionUID = 1L;
+
+}
diff --git a/group22/627559964/src/com/coderising/download/api/ConnectionManager.java b/group22/627559964/src/com/coderising/download/api/ConnectionManager.java
new file mode 100644
index 0000000000..ce045393b1
--- /dev/null
+++ b/group22/627559964/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;	
+}
diff --git a/group22/627559964/src/com/coderising/download/api/DownloadListener.java b/group22/627559964/src/com/coderising/download/api/DownloadListener.java
new file mode 100644
index 0000000000..35ac488d20
--- /dev/null
+++ b/group22/627559964/src/com/coderising/download/api/DownloadListener.java
@@ -0,0 +1,7 @@
+package com.coderising.download.api;
+
+public interface DownloadListener {
+
+	public void notifyFinished();
+
+}
diff --git a/group22/627559964/src/com/coderising/download/impl/ConnectionImpl.java b/group22/627559964/src/com/coderising/download/impl/ConnectionImpl.java
new file mode 100644
index 0000000000..82b7920450
--- /dev/null
+++ b/group22/627559964/src/com/coderising/download/impl/ConnectionImpl.java
@@ -0,0 +1,75 @@
+package com.coderising.download.impl;
+
+import java.io.ByteArrayOutputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.RandomAccessFile;
+import java.net.HttpURLConnection;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLConnection;
+import java.util.Arrays;
+
+import com.coderising.download.api.Connection;
+
+public class ConnectionImpl implements Connection{
+	
+	private URL url;
+	
+	public ConnectionImpl(String _url) {
+		try {
+			url = new URL(_url);
+		} catch (MalformedURLException e) {
+			e.printStackTrace();
+		}
+	}
+
+	@Override
+	public byte[] read(int startPos, int endPos) throws IOException {
+		HttpURLConnection connection = (HttpURLConnection) url.openConnection();
+		connection.setRequestProperty("Range", "bytes=" + startPos + "-" + endPos);
+		InputStream in = connection.getInputStream();
+		
+		byte[] buffer = new byte[1024];
+		int length = endPos - startPos + 1;
+		ByteArrayOutputStream out = new ByteArrayOutputStream();
+		while(out.size() < length) {
+			int len = in.read(buffer);
+			if(len < 0) {
+				break;
+			}
+			out.write(buffer, 0, len);
+		}
+		
+		if(out.size() > length) {
+			byte[] file = out.toByteArray();
+			return Arrays.copyOf(file, length);
+		}
+		
+		return out.toByteArray();
+	}
+
+	@Override
+	public int getContentLength() {
+		
+        URLConnection con;
+		try {
+			con = url.openConnection();
+			
+			return con.getContentLength(); 
+			
+		} catch (IOException e) {			
+			e.printStackTrace();
+		}  
+        
+		return -1;
+	}
+
+	@Override
+	public void close() {
+
+	}
+
+}
diff --git a/group22/627559964/src/com/coderising/download/impl/ConnectionManagerImpl.java b/group22/627559964/src/com/coderising/download/impl/ConnectionManagerImpl.java
new file mode 100644
index 0000000000..9719f8ff51
--- /dev/null
+++ b/group22/627559964/src/com/coderising/download/impl/ConnectionManagerImpl.java
@@ -0,0 +1,20 @@
+package com.coderising.download.impl;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.MalformedURLException;
+import java.net.URL;
+
+import com.coderising.download.api.Connection;
+import com.coderising.download.api.ConnectionException;
+import com.coderising.download.api.ConnectionManager;
+
+public class ConnectionManagerImpl implements ConnectionManager {
+
+	@Override
+	public Connection open(String url) throws ConnectionException {
+
+		return new ConnectionImpl(url);
+	}
+
+}
diff --git a/group22/627559964/src/com/coding/basic/LinkedList.java b/group22/627559964/src/com/coding/basic/LinkedList.java
index dcae1fb835..39b0250ae3 100644
--- a/group22/627559964/src/com/coding/basic/LinkedList.java
+++ b/group22/627559964/src/com/coding/basic/LinkedList.java
@@ -1,7 +1,7 @@
 package com.coding.basic;
 
 /**
- * �Զ���LinkList
+ * 自定义LinkList
  * 
  * @author xiongrui233
  *
@@ -9,7 +9,7 @@
 public class LinkedList implements List {
 
 	/**
-	 * ���������ڵ�ṹ
+	 * 定义链表节点结构
 	 * 
 	 * @author xiongrui233
 	 *
@@ -19,7 +19,7 @@ private static class Node {
 		Node next;
 	}
 
-	// �����ڵ�
+	// 链表节点
 	private Node head = new Node();
 
 	private int size = 0;
@@ -29,7 +29,7 @@ public LinkedList() {
 	}
 
 	/**
-	 * ����Ԫ��
+	 * 添加元素
 	 * 
 	 * @param o
 	 */
@@ -38,7 +38,7 @@ public void add(Object o) {
 	}
 
 	/**
-	 * ����Ԫ��
+	 * 添加元素
 	 * 
 	 * @param index
 	 * @param o
@@ -64,7 +64,7 @@ public void add(int index, Object o) {
 	}
 
 	/**
-	 * ��ȡԪ��
+	 * 获取元素
 	 * 
 	 * @param index
 	 */
@@ -77,7 +77,7 @@ public Object get(int index) {
 	}
 
 	/**
-	 * ɾ��Ԫ��
+	 * 删除元素
 	 * 
 	 * @param index
 	 */
@@ -102,7 +102,7 @@ public Object remove(int index) {
 	}
 
 	/**
-	 * ����LinkedList�Ĵ�С
+	 * 返回LinkedList的大小
 	 * 
 	 * @return size
 	 */
@@ -111,7 +111,7 @@ public int size() {
 	}
 
 	/**
-	 * ��LinkedList��һ��λ������Ԫ��
+	 * 在LinkedList第一的位置添加元素
 	 * 
 	 * @param o
 	 */
@@ -120,7 +120,7 @@ public void addFirst(Object o) {
 	}
 
 	/**
-	 * ��LinkedList�������Ԫ��
+	 * 在LinkedList最后添加元素
 	 * @param o
 	 */
 	public void addLast(Object o) {
@@ -135,7 +135,7 @@ public void addLast(Object o) {
 	}
 
 	/**
-	 * �Ƴ�������һλԪ��
+	 * 移除链表第一位元素
 	 * 
 	 * @return obj
 	 */
@@ -144,7 +144,7 @@ public Object removeFirst() {
 	}
 
 	/**
-	 * �Ƴ��������һλԪ��
+	 * 移除链表最后一位元素
 	 * 
 	 * @return obj
 	 */
@@ -153,7 +153,7 @@ public Object removeLast() {
 	}
 
 	/**
-	 * ʵ��Iterator�ӿ�
+	 * 实现Iterator接口
 	 * 
 	 * @return Iterator
 	 */
@@ -185,7 +185,7 @@ public Object next() {
 	}
 
 	/**
-	 * �Ѹ��������� ��������Ϊ 3->7->10 , ���ú��Ϊ 10->7->3
+	 * 把该链表逆置 例如链表为 3->7->10 , 逆置后变为 10->7->3
 	 */
 	public LinkedList reverse() {
 		LinkedList lis = new LinkedList();
@@ -196,8 +196,8 @@ public LinkedList reverse() {
 	}
 
 	/**
-	 * ɾ��һ����������ǰ�벿�� ���磺list = 2->5->7->8 , ɾ���Ժ��ֵΪ 7->8 ���list = 2->5->7->8->10
-	 * ,ɾ���Ժ��ֵΪ7,8,10
+	 * 删除一个单链表的前半部分 例如：list = 2->5->7->8 , 删除以后的值为 7->8 如果list = 2->5->7->8->10
+	 * ,删除以后的值为7,8,10
 	 */
 	public void removeFirstHalf() {
 		int mid = size/2;
@@ -207,7 +207,7 @@ public void removeFirstHalf() {
 	}
 
 	/**
-	 * �ӵ�i��Ԫ�ؿ�ʼ�� ɾ��length ��Ԫ�� �� ע��i��0��ʼ
+	 * 从第i个元素开始， 删除length 个元素 ， 注意i从0开始
 	 * 
 	 * @param i
 	 * @param length
@@ -225,9 +225,9 @@ public void remove(int i, int length) {
 	}
 
 	/**
-	 * �ٶ���ǰ������list���������������е����� �ӵ�ǰ������ȡ����Щlist��ָ����Ԫ�� ���統ǰ���� =
+	 * 假定当前链表和list均包含已升序排列的整数 从当前链表中取出那些list所指定的元素 例如当前链表 =
 	 * 11->101->201->301->401->501->601->701 listB = 1->3->4->6
-	 * ���صĽ��Ӧ����[101,301,401,601]
+	 * 返回的结果应该是[101,301,401,601]
 	 * 
 	 * @param list
 	 */
@@ -243,7 +243,7 @@ public int[] getElements(LinkedList list) {
 	}
 
 	/**
-	 * ��֪�����е�Ԫ����ֵ�����������У����Ե��������洢�ṹ�� �ӵ�ǰ��������ɾ����list�г��ֵ�Ԫ��
+	 * 已知链表中的元素以值递增有序排列，并以单链表作存储结构。 从当前链表中中删除在list中出现的元素
 	 * 
 	 * @param list
 	 */
@@ -261,7 +261,7 @@ public void subtract(LinkedList list) {
 	}
 
 	/**
-	 * ��֪��ǰ�����е�Ԫ����ֵ�����������У����Ե��������洢�ṹ�� ɾ����������ֵ��ͬ�Ķ���Ԫ�أ�ʹ�ò���������Ա�������Ԫ�ص�ֵ������ͬ��
+	 * 已知当前链表中的元素以值递增有序排列，并以单链表作存储结构。 删除表中所有值相同的多余元素（使得操作后的线性表中所有元素的值均不相同）
 	 */
 	public void removeDuplicateValues() {
 		for (int i = 0; i < this.size; i++) {
@@ -276,7 +276,7 @@ public void removeDuplicateValues() {
 	}
 
 	/**
-	 * ��֪�����е�Ԫ����ֵ�����������У����Ե��������洢�ṹ�� ��дһ��Ч���㷨��ɾ����������ֵ����min��С��max��Ԫ�أ������д���������Ԫ�أ�
+	 * 已知链表中的元素以值递增有序排列，并以单链表作存储结构。 试写一高效的算法，删除表中所有值大于min且小于max的元素（若表中存在这样的元素）
 	 * 
 	 * @param min
 	 * @param max
@@ -293,8 +293,8 @@ public void removeRange(int min, int max) {
 	}
 
 	/**
-	 * ���赱ǰ�����Ͳ���listָ������������Ԫ����ֵ�����������У�ͬһ���е�Ԫ��ֵ������ͬ��
-	 * ��Ҫ������������C����Ԫ��Ϊ��ǰ������list��Ԫ�صĽ������ұ�C�е�Ԫ������ֵ������������
+	 * 假设当前链表和参数list指定的链表均以元素依值递增有序排列（同一表中的元素值各不相同）
+	 * 现要求生成新链表C，其元素为当前链表和list中元素的交集，且表C中的元素有依值递增有序排列
 	 * TODO
 	 * @param list
 	 */
diff --git a/group22/627559964/src/demo/SimpleDownLoad.java b/group22/627559964/src/demo/SimpleDownLoad.java
new file mode 100644
index 0000000000..1931fd5d38
--- /dev/null
+++ b/group22/627559964/src/demo/SimpleDownLoad.java
@@ -0,0 +1,54 @@
+package demo;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLConnection;
+
+public class SimpleDownLoad {
+	
+	public static void main(String[] args) {
+		String downUrl = "https://ss0.baidu.com/-Po3dSag_xI4khGko9WTAnF6hhy/super/crop=378,138,1512,942/sign=9cca06797b3e6709aa4f1fbf06f4a805/f9198618367adab471a1e11d8fd4b31c8701e47f.jpg";
+		String dirUrl = "C:\\Users\\Administrator\\Desktop\\1.jpg";
+		
+		InputStream in = null;
+		OutputStream out = null;
+		
+		try {
+			URL url = new URL(downUrl);
+			URLConnection connection = url.openConnection();
+			in = connection.getInputStream();
+			
+			File file = new File(dirUrl);
+			out = new FileOutputStream(file);
+			
+			byte[] files = new byte[1024];
+			int length = 0;
+			while ((length = in.read(files)) > -1) {
+				out.write(files, 0, length);
+			}
+			
+		} catch (MalformedURLException e) {
+			// TODO Auto-generated catch block
+			e.printStackTrace();
+		} catch (IOException e) {
+			// TODO Auto-generated catch block
+			e.printStackTrace();
+		} finally {
+			try {
+				in.close();
+				out.close();
+			} catch (IOException e) {
+				// TODO Auto-generated catch block
+				e.printStackTrace();
+			}
+		}
+		
+		
+	}
+	
+}