content: /*
   * Copyright (c) 2013. wyouflf (wyouflf@gmail.com)
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.lidroid.xutils.bitmap.download;
  
  import com.lidroid.xutils.BitmapUtils;
  import com.lidroid.xutils.util.IOUtils;
  import com.lidroid.xutils.util.LogUtils;
  import com.lidroid.xutils.util.OtherUtils;
  
  import java.io.*;
  import java.net.URL;
  import java.net.URLConnection;
  
  public class DefaultDownloader extends Downloader {
  
      /**
       * Download bitmap to outputStream by uri.
       *
       * @param uri          file path, assets path(assets/xxx) or http url.
       * @param outputStream
       * @param task
       * @return The expiry time stamp or -1 if failed to download.
       */
      @Override
      public long downloadToStream(String uri, OutputStream outputStream, final BitmapUtils.BitmapLoadTask<?> task) {
  
          if (task == null || task.isCancelled() || task.getTargetContainer() == null) return -1;
  
          URLConnection urlConnection = null;
          BufferedInputStream bis = null;
  
          OtherUtils.trustAllHttpsURLConnection();
  
          long result = -1;
          long fileLen = 0;
          long currCount = 0;  
          try {
          	//分三种方式获取图片
              if (uri.startsWith("/")) { 
              	//sd卡获取
                  FileInputStream fileInputStream = new FileInputStream(uri);
                  fileLen = fileInputStream.available();
                  bis = new BufferedInputStream(fileInputStream);
                  result = System.currentTimeMillis() + this.getDefaultExpiry();
              } else if (uri.startsWith("assets/")) { 
              	//资产文件夹
                  InputStream inputStream = this.getContext().getAssets().open(uri.substring(7, uri.length()));
                  fileLen = inputStream.available();
                  bis = new BufferedInputStream(inputStream);
                  result = Long.MAX_VALUE;
              } else {  
              	//网络
                  final URL url = new URL(uri);
                  urlConnection = url.openConnection();
                  urlConnection.setConnectTimeout(this.getDefaultConnectTimeout());
                  urlConnection.setReadTimeout(this.getDefaultReadTimeout());
                  bis = new BufferedInputStream(urlConnection.getInputStream());
                  result = urlConnection.getExpiration();
                  result = result < System.currentTimeMillis() ? System.currentTimeMillis() + this.getDefaultExpiry() : result;
                  fileLen = urlConnection.getContentLength();
              }
  
              if (task.isCancelled() || task.getTargetContainer() == null) return -1;
  
              byte[] buffer = new byte[4096];
              int len = 0;
              BufferedOutputStream out = new BufferedOutputStream(outputStream);
              while ((len = bis.read(buffer)) != -1) {
                  out.write(buffer, 0, len);
                  currCount += len;
                  if (task.isCancelled() || task.getTargetContainer() == null) return -1;
                  task.updateProgress(fileLen, currCount);     //回调
              }
              out.flush();
          } catch (Throwable e) {
              result = -1;
              LogUtils.e(e.getMessage(), e);
          } finally {
              IOUtils.closeQuietly(bis);
          }
          return result;
      }
  }
  