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      1 /*
      2  * Copyright (C) 2010 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.android.gallery3d.data;
     18 
     19 import com.android.gallery3d.common.Utils;
     20 import com.android.gallery3d.util.ThreadPool.CancelListener;
     21 import com.android.gallery3d.util.ThreadPool.JobContext;
     22 
     23 import java.io.ByteArrayOutputStream;
     24 import java.io.File;
     25 import java.io.FileOutputStream;
     26 import java.io.IOException;
     27 import java.io.InputStream;
     28 import java.io.InterruptedIOException;
     29 import java.io.OutputStream;
     30 import java.net.URL;
     31 
     32 public class DownloadUtils {
     33     private static final String TAG = "DownloadService";
     34 
     35     public static boolean requestDownload(JobContext jc, URL url, File file) {
     36         FileOutputStream fos = null;
     37         try {
     38             fos = new FileOutputStream(file);
     39             return download(jc, url, fos);
     40         } catch (Throwable t) {
     41             return false;
     42         } finally {
     43             Utils.closeSilently(fos);
     44         }
     45     }
     46 
     47     public static byte[] requestDownload(JobContext jc, URL url) {
     48         ByteArrayOutputStream baos = null;
     49         try {
     50             baos = new ByteArrayOutputStream();
     51             if (!download(jc, url, baos)) {
     52                 return null;
     53             }
     54             return baos.toByteArray();
     55         } catch (Throwable t) {
     56             Log.w(TAG, t);
     57             return null;
     58         } finally {
     59             Utils.closeSilently(baos);
     60         }
     61     }
     62 
     63     public static void dump(JobContext jc, InputStream is, OutputStream os)
     64             throws IOException {
     65         byte buffer[] = new byte[4096];
     66         int rc = is.read(buffer, 0, buffer.length);
     67         final Thread thread = Thread.currentThread();
     68         jc.setCancelListener(new CancelListener() {
     69             public void onCancel() {
     70                 thread.interrupt();
     71             }
     72         });
     73         while (rc > 0) {
     74             if (jc.isCancelled()) throw new InterruptedIOException();
     75             os.write(buffer, 0, rc);
     76             rc = is.read(buffer, 0, buffer.length);
     77         }
     78         jc.setCancelListener(null);
     79         Thread.interrupted(); // consume the interrupt signal
     80     }
     81 
     82     public static boolean download(JobContext jc, URL url, OutputStream output) {
     83         InputStream input = null;
     84         try {
     85             input = url.openStream();
     86             dump(jc, input, output);
     87             return true;
     88         } catch (Throwable t) {
     89             Log.w(TAG, "fail to download", t);
     90             return false;
     91         } finally {
     92             Utils.closeSilently(input);
     93         }
     94     }
     95 }