1 /* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not 5 * use this file except in compliance with the License. You may obtain a copy of 6 * 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, WITHOUT 12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 13 * License for the specific language governing permissions and limitations under 14 * the License. 15 */ 16 17 package com.android.inputmethod.dictionarypack; 18 19 import android.app.DownloadManager; 20 import android.app.DownloadManager.Query; 21 import android.app.DownloadManager.Request; 22 import android.content.Context; 23 import android.database.Cursor; 24 import android.database.sqlite.SQLiteException; 25 import android.os.ParcelFileDescriptor; 26 import android.util.Log; 27 28 import java.io.FileNotFoundException; 29 30 /** 31 * A class to help with calling DownloadManager methods. 32 * 33 * Mostly, the problem here is that most methods from DownloadManager may throw SQL exceptions if 34 * they can't open the database on disk. We want to avoid crashing in these cases but can't do 35 * much more, so this class insulates the callers from these. SQLiteException also inherit from 36 * RuntimeException so they are unchecked :( 37 * While we're at it, we also insulate callers from the cases where DownloadManager is disabled, 38 * and getSystemService returns null. 39 */ 40 public class DownloadManagerWrapper { 41 private final static String TAG = DownloadManagerWrapper.class.getSimpleName(); 42 private final DownloadManager mDownloadManager; 43 44 public DownloadManagerWrapper(final Context context) { 45 this((DownloadManager) context.getSystemService(Context.DOWNLOAD_SERVICE)); 46 } 47 48 private DownloadManagerWrapper(final DownloadManager downloadManager) { 49 mDownloadManager = downloadManager; 50 } 51 52 public void remove(final long... ids) { 53 try { 54 if (null != mDownloadManager) { 55 mDownloadManager.remove(ids); 56 } 57 } catch (IllegalArgumentException e) { 58 // This is expected to happen on boot when the device is encrypted. 59 } catch (SQLiteException e) { 60 // We couldn't remove the file from DownloadManager. Apparently, the database can't 61 // be opened. It may be a problem with file system corruption. In any case, there is 62 // not much we can do apart from avoiding crashing. 63 Log.e(TAG, "Can't remove files with ID " + ids + " from download manager", e); 64 } 65 } 66 67 public ParcelFileDescriptor openDownloadedFile(final long fileId) throws FileNotFoundException { 68 try { 69 if (null != mDownloadManager) { 70 return mDownloadManager.openDownloadedFile(fileId); 71 } 72 } catch (IllegalArgumentException e) { 73 // This is expected to happen on boot when the device is encrypted. 74 } catch (SQLiteException e) { 75 Log.e(TAG, "Can't open downloaded file with ID " + fileId, e); 76 } 77 // We come here if mDownloadManager is null or if an exception was thrown. 78 throw new FileNotFoundException(); 79 } 80 81 public Cursor query(final Query query) { 82 try { 83 if (null != mDownloadManager) { 84 return mDownloadManager.query(query); 85 } 86 } catch (IllegalArgumentException e) { 87 // This is expected to happen on boot when the device is encrypted. 88 } catch (SQLiteException e) { 89 Log.e(TAG, "Can't query the download manager", e); 90 } 91 // We come here if mDownloadManager is null or if an exception was thrown. 92 return null; 93 } 94 95 public long enqueue(final Request request) { 96 try { 97 if (null != mDownloadManager) { 98 return mDownloadManager.enqueue(request); 99 } 100 } catch (IllegalArgumentException e) { 101 // This is expected to happen on boot when the device is encrypted. 102 } catch (SQLiteException e) { 103 Log.e(TAG, "Can't enqueue a request with the download manager", e); 104 } 105 return 0; 106 } 107 } 108
