FileDownloadThread:
package com.amos.app;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.net.URL;
import java.net.URLConnection;
import android.util.Log;
/**
* 文件下载类
*
* @author yangxiaolong
* @2014-5-6
*/
public class FileDownloadThread extends Thread {
private static final String TAG = FileDownloadThread.class.getSimpleName();
/** 当前下载是否完成 */
private boolean isCompleted = false;
/** 当前下载文件长度 */
private int downloadLength = 0;
/** 文件保存路径 */
private File file;
/** 文件下载路径 */
private URL downloadUrl;
/** 当前下载线程ID */
private int threadId;
/** 线程下载数据长度 */
private int blockSize;
/**
*
* @param url:文件下载地址
* @param file:文件保存路径
* @param blocksize:下载数据长度
* @param threadId:线程ID
*/
public FileDownloadThread(URL downloadUrl, File file, int blocksize,
int threadId) {
this.downloadUrl = downloadUrl;
this.file = file;
this.threadId = threadId;
this.blockSize = blocksize;
}
@Override
public void run() {
BufferedInputStream bis = null;
RandomAccessFile raf = null;
try {
URLConnection conn = downloadUrl.openConnection();
conn.setAllowUserInteraction(true);
int startPos = blockSize * (threadId - 1);//开始位置
int endPos = blockSize * threadId - 1;//结束位置
//设置当前线程下载的起点、终点
conn.setRequestProperty("Range", "bytes=" + startPos + "-" + endPos);
System.out.println(Thread.currentThread().getName() + " bytes="
+ startPos + "-" + endPos);
byte[] buffer = new byte[1024];
bis = new BufferedInputStream(conn.getInputStream());
raf = new RandomAccessFile(file, "rwd");
raf.seek(startPos);
int len;
while ((len = bis.read(buffer, 0, 1024)) != -1) {
raf.write(buffer, 0, len);
downloadLength += len;
}
isCompleted = true;
Log.d(TAG, "current thread task has finished,all size:"
+ downloadLength);
} catch (IOException e) {
e.printStackTrace();
} finally {
if (bis != null) {
try {
bis.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (raf != null) {
try {
raf.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
/**
* 线程文件是否下载完毕
*/
public boolean isCompleted() {
return isCompleted;
}
/**
* 线程下载文件长度
*/
public int getDownloadLength() {
return downloadLength;
}
}
效果图：
