package com.arialyy.downloadutil; import android.content.Context; import android.support.annotation.NonNull; import android.util.Log; import android.util.SparseArray; import com.arialyy.downloadutil.inf.IDownloadListener; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.io.RandomAccessFile; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import java.util.Properties; /** * Created by lyy on 2015/8/25. * 下载工具类 */ public class DownLoadUtil { private static final String TAG = "DownLoadUtil"; //下载监听 private IDownloadListener mListener; /** * 线程数 */ private static final int THREAD_NUM = 3; /** * 已经完成下载任务的线程数量 */ private int mCompleteThreadNum = 0; private long mCurrentLocation; private boolean isDownloading = false; private boolean isStop = false; private boolean isCancel = false; private static final int TIME_OUT = 5000; //超时时间 boolean newTask = true; private int mCancelNum = 0; private int mStopNum = 0; public DownLoadUtil() { } /** * 获取当前下载位置 * * @return */ public long getCurrentLocation() { return mCurrentLocation; } public boolean isDownloading() { return isDownloading; } /** * 取消下载 */ public void cancelDownload() { isCancel = true; } /** * 停止下载 */ public void stopDownload() { isStop = true; } /** * 多线程断点续传下载文件，暂停和继续 * * @param context 必须添加该参数，不能使用全局变量的context * @param downloadUrl 下载路径 * @param filePath 保存路径 * @param downloadListener 下载进度监听 {@link DownloadListener} */ public void download(final Context context, @NonNull final String downloadUrl, @NonNull final String filePath, @NonNull final DownloadListener downloadListener) { isDownloading = true; mCurrentLocation = 0; isStop = false; isCancel = false; mCancelNum = 0; mStopNum = 0; final File dFile = new File(filePath); //读取已完成的线程数 final File configFile = new File(context.getFilesDir().getPath() + "/temp/" + dFile.getName() + ".properties"); try { if (!configFile.exists()) { //记录文件被删除，则重新下载 newTask = true; Util.createFile(configFile.getPath()); } else { newTask = false; } } catch (Exception e) { e.printStackTrace(); mListener.onFail(); return; } newTask = !dFile.exists(); new Thread(new Runnable() { @Override public void run() { try { mListener = downloadListener; URL url = new URL(downloadUrl); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); conn.setRequestMethod("GET"); conn.setRequestProperty("Charset", "UTF-8"); conn.setConnectTimeout(TIME_OUT); conn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"); conn.setRequestProperty("Accept", "image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*"); conn.connect(); int len = conn.getContentLength(); if (len < 0) { //网络被劫持时会出现这个问题 mListener.onFail(); return; } int code = conn.getResponseCode(); if (code == 200) { int fileLength = conn.getContentLength(); //必须建一个文件 Util.createFile(filePath); RandomAccessFile file = new RandomAccessFile(filePath, "rwd"); //设置文件长度 file.setLength(fileLength); mListener.onPreDownload(conn); //分配每条线程的下载区间 Properties pro = null; pro = Util.loadConfig(configFile); int blockSize = fileLength / THREAD_NUM; SparseArray tasks = new SparseArray<>(); for (int i = 0; i < THREAD_NUM; i++) { long startL = i * blockSize, endL = (i + 1) * blockSize; Object state = pro.getProperty(dFile.getName() + "_state_" + i); if (state != null && Integer.parseInt(state + "") == 1) { //该线程已经完成 mCurrentLocation += endL - startL; Log.d(TAG, "++++++++++ 线程_" + i + "_已经下载完成 ++++++++++"); mCompleteThreadNum++; if (mCompleteThreadNum == THREAD_NUM) { if (configFile.exists()) { configFile.delete(); } mListener.onComplete(); isDownloading = false; System.gc(); return; } continue; } //分配下载位置 Object record = pro.getProperty(dFile.getName() + "_record_" + i); if (!newTask && record != null && Long.parseLong(record + "") > 0) { //如果有记录，则恢复下载 Long r = Long.parseLong(record + ""); mCurrentLocation += r - startL; Log.d(TAG, "++++++++++ 线程_" + i + "_恢复下载 ++++++++++"); mListener.onChildResume(r); startL = r; } if (i == (THREAD_NUM - 1)) { endL = fileLength;//如果整个文件的大小不为线程个数的整数倍，则最后一个线程的结束位置即为文件的总长度 } DownloadEntity entity = new DownloadEntity(context, fileLength, downloadUrl, dFile, i, startL, endL); DownLoadTask task = new DownLoadTask(entity); tasks.put(i, new Thread(task)); } if (mCurrentLocation > 0) { mListener.onResume(mCurrentLocation); } else { mListener.onStart(mCurrentLocation); } for (int i = 0, count = tasks.size(); i < count; i++) { Thread task = tasks.get(i); if (task != null) { task.start(); } } } else { Log.e(TAG, "下载失败，返回码：" + code); isDownloading = false; System.gc(); mListener.onFail(); } } catch (IOException e) { Log.e(TAG, "下载失败【downloadUrl:" + downloadUrl + "】\n【filePath:" + filePath + "】" + Util.getPrintException(e)); isDownloading = false; mListener.onFail(); } } }).start(); } /** * 多线程下载任务类,不能使用AsyncTask来进行多线程下载，因为AsyncTask是串行执行的，这种方式下载速度太慢了 */ private class DownLoadTask implements Runnable { private static final String TAG = "DownLoadTask"; private DownloadEntity dEntity; private String configFPath; public DownLoadTask(DownloadEntity downloadInfo) { this.dEntity = downloadInfo; configFPath = dEntity.context.getFilesDir().getPath() + "/temp/" + dEntity.tempFile.getName() + ".properties"; } @Override public void run() { try { Log.d(TAG, "线程_" + dEntity.threadId + "_正在下载【" + "开始位置 : " + dEntity.startLocation + "，结束位置：" + dEntity.endLocation + "】"); URL url = new URL(dEntity.downloadUrl); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); //在头里面请求下载开始位置和结束位置 conn.setRequestProperty("Range", "bytes=" + dEntity.startLocation + "-" + dEntity.endLocation); conn.setRequestMethod("GET"); conn.setRequestProperty("Charset", "UTF-8"); conn.setConnectTimeout(TIME_OUT); conn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"); conn.setRequestProperty("Accept", "image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*"); conn.setReadTimeout(2000); //设置读取流的等待时间,必须设置该参数 InputStream is = conn.getInputStream(); //创建可设置位置的文件 RandomAccessFile file = new RandomAccessFile(dEntity.tempFile, "rwd"); //设置每条线程写入文件的位置 file.seek(dEntity.startLocation); byte[] buffer = new byte[1024]; int len; //当前子线程的下载位置 long currentLocation = dEntity.startLocation; while ((len = is.read(buffer)) != -1) { if (isCancel) { Log.d(TAG, "++++++++++ thread_" + dEntity.threadId + "_cancel ++++++++++"); break; } if (isStop) { break; } //把下载数据数据写入文件 file.write(buffer, 0, len); synchronized (DownLoadUtil.this) { mCurrentLocation += len; mListener.onProgress(mCurrentLocation); } currentLocation += len; } file.close(); is.close(); if (isCancel) { synchronized (DownLoadUtil.this) { mCancelNum++; if (mCancelNum == THREAD_NUM) { File configFile = new File(configFPath); if (configFile.exists()) { configFile.delete(); } if (dEntity.tempFile.exists()) { dEntity.tempFile.delete(); } Log.d(TAG, "++++++++++++++++ onCancel +++++++++++++++++"); isDownloading = false; mListener.onCancel(); System.gc(); } } return; } //停止状态不需要删除记录文件 if (isStop) { synchronized (DownLoadUtil.this) { mStopNum++; String location = String.valueOf(currentLocation); Log.i(TAG, "thread_" + dEntity.threadId + "_stop, stop location ==> " + currentLocation); writeConfig(dEntity.tempFile.getName() + "_record_" + dEntity.threadId, location); if (mStopNum == THREAD_NUM) { Log.d(TAG, "++++++++++++++++ onStop +++++++++++++++++"); isDownloading = false; mListener.onStop(mCurrentLocation); System.gc(); } } return; } Log.i(TAG, "线程【" + dEntity.threadId + "】下载完毕"); writeConfig(dEntity.tempFile.getName() + "_state_" + dEntity.threadId, 1 + ""); mListener.onChildComplete(dEntity.endLocation); mCompleteThreadNum++; if (mCompleteThreadNum == THREAD_NUM) { File configFile = new File(configFPath); if (configFile.exists()) { configFile.delete(); } mListener.onComplete(); isDownloading = false; System.gc(); } } catch (MalformedURLException e) { e.printStackTrace(); isDownloading = false; mListener.onFail(); } catch (IOException e) { Log.e(TAG, "下载失败【" + dEntity.downloadUrl + "】" + Util.getPrintException(e)); isDownloading = false; mListener.onFail(); } catch (Exception e) { Log.e(TAG, "获取流失败" + Util.getPrintException(e)); isDownloading = false; mListener.onFail(); } } /** * 将记录写入到配置文件 * * @param record */ private void writeConfig(String key, String record) throws IOException { File configFile = new File(configFPath); Properties pro = Util.loadConfig(configFile); pro.setProperty(key, record); Util.saveConfig(configFile, pro); } } /** * 子线程下载信息类 */ private class DownloadEntity { //文件大小 long fileSize; String downloadUrl; int threadId; long startLocation; long endLocation; File tempFile; Context context; public DownloadEntity(Context context, long fileSize, String downloadUrl, File file, int threadId, long startLocation, long endLocation) { this.fileSize = fileSize; this.downloadUrl = downloadUrl; this.tempFile = file; this.threadId = threadId; this.startLocation = startLocation; this.endLocation = endLocation; this.context = context; } } }