1 /*
2  * Copyright (C) 2012 Google Inc.
3  * Licensed to The Android Open Source Project.
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  *      http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
18 package com.android.mail.browse;
19 
20 import com.google.common.collect.Maps;
21 
22 import android.content.Context;
23 import android.content.CursorLoader;
24 import android.database.Cursor;
25 import android.database.CursorWrapper;
26 import android.net.Uri;
27 
28 import com.android.mail.providers.Attachment;
29 import com.android.mail.providers.UIProvider;
30 
31 import java.util.Map;
32 
33 public class AttachmentLoader extends CursorLoader {
34 
AttachmentLoader(Context c, Uri uri)35     public AttachmentLoader(Context c, Uri uri) {
36         super(c, uri, UIProvider.ATTACHMENT_PROJECTION, null, null, null);
37     }
38 
39     @Override
loadInBackground()40     public Cursor loadInBackground() {
41         return new AttachmentCursor(super.loadInBackground());
42     }
43 
44     public static class AttachmentCursor extends CursorWrapper {
45 
46         private Map<String, Attachment> mCache = Maps.newHashMap();
47 
AttachmentCursor(Cursor inner)48         private AttachmentCursor(Cursor inner) {
49             super(inner);
50         }
51 
get()52         public Attachment get() {
53             final String uri = getWrappedCursor().getString(UIProvider.ATTACHMENT_URI_COLUMN);
54             Attachment m = mCache.get(uri);
55             if (m == null) {
56                 m = new Attachment(this);
57                 mCache.put(uri, m);
58             }
59             return m;
60         }
61     }
62 }
63