Android实现多线程下载文件的方法

Log.i("bb", "======================fileSize:"+fileSize); //计算每个线程要下载的数据量

blockSize = fileSize / threadNum; // 解决整除后百分比计算误差

downloadSizeMore = (fileSize % threadNum); File file = new File(fileName);

for (int i = 0; i < threadNum; i++) { Log.i("bb", "======================i:"+i);

//启动线程，分别下载自己需要下载的部分 FileDownloadThread fdt = new FileDownloadThread(url, file, i * blockSize, (i + 1) * blockSize - 1);

fdt.setName("Thread" + i); fdt.start();

fds[i] = fdt; }

boolean finished = false; while (!finished) {

// 先把整除的余数搞定 downloadedSize = downloadSizeMore;

finished = true; for (int i = 0; i < fds.length; i++) {

downloadedSize += fds[i].getDownloadSize(); if (!fds[i].isFinished()) {

finished = false; }

} handler.sendEmptyMessage(0);

//线程暂停一秒sleep(1000); }

} catch (Exception e) {

e.printStackTrace(); }

} }

}

这里启动线程将文件分割为几个部分，每一个部分再启动一个线程去下载数据