SourceShortcutRefresher.java revision f252dc7a25ba08b973ecc1cfbbce58eb78d42167 
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
17package com.android.quicksearchbox;
18
19import com.android.quicksearchbox.util.NamedTask;
20import com.android.quicksearchbox.util.NamedTaskExecutor;
21
22import java.util.Collections;
23import java.util.HashSet;
24import java.util.Set;
25
26/**
27 * Refreshes shortcuts from their source.
28 */
29class SourceShortcutRefresher implements ShortcutRefresher {
30
31    private final NamedTaskExecutor mExecutor;
32
33    private final Set<String> mRefreshed = Collections.synchronizedSet(new HashSet<String>());
34
35    /**
36     * Create a ShortcutRefresher that will refresh shortcuts using the given executor.
37     *
38     * @param executor Used to execute the tasks.
39     */
40    public SourceShortcutRefresher(NamedTaskExecutor executor) {
41        mExecutor = executor;
42    }
43
44    /**
45     * Sends off the refresher tasks.
46     *
47     * @param shortcuts The shortcuts to refresh.
48     * @param listener Who to report back to.
49     */
50    public void refresh(SuggestionCursor shortcuts, final Listener listener) {
51        int count = shortcuts.getCount();
52        for (int i = 0; i < count; i++) {
53            shortcuts.moveTo(i);
54            if (shouldRefresh(shortcuts)) {
55                String shortcutId = shortcuts.getShortcutId();
56                Source source = shortcuts.getSuggestionSource();
57
58                // If we can't find the source then invalidate the shortcut.
59                // Otherwise, send off the refresh task.
60                if (source == null) {
61                    listener.onShortcutRefreshed(source, shortcutId, null);
62                } else {
63                    String extraData = shortcuts.getSuggestionIntentExtraData();
64                    ShortcutRefreshTask refreshTask = new ShortcutRefreshTask(
65                            source, shortcutId, extraData, listener);
66                    mExecutor.execute(refreshTask);
67                }
68            }
69        }
70    }
71
72    /**
73     * Returns true if the given shortcut requires refreshing.
74     */
75    public boolean shouldRefresh(SuggestionCursor shortcut) {
76        return shortcut.getShortcutId() != null
77                && ! mRefreshed.contains(makeKey(shortcut));
78    }
79
80    /**
81     * Indicate that the shortcut no longer requires refreshing.
82     */
83    public void onShortcutRefreshed(SuggestionCursor shortcut) {
84        mRefreshed.add(makeKey(shortcut));
85    }
86
87    /**
88     * Reset internal state.  This results in all shortcuts requiring refreshing.
89     */
90    public void reset() {
91        mRefreshed.clear();
92    }
93
94    /**
95     * Cancel any pending shortcut refresh requests.
96     */
97    public void cancelPendingTasks() {
98        mExecutor.cancelPendingTasks();
99    }
100
101    private static String makeKey(SuggestionCursor shortcut) {
102        return shortcut.getSuggestionSource().getName() + "#"
103                + shortcut.getShortcutId();
104    }
105
106    /**
107     * Refreshes a shortcut with a source and reports the result to a
108     * {@link ShortcutRefresher.Listener}.
109     */
110    private class ShortcutRefreshTask implements NamedTask {
111        private final Source mSource;
112        private final String mShortcutId;
113        private final String mExtraData;
114        private final Listener mListener;
115
116        /**
117         * @param source The source that should validate the shortcut.
118         * @param shortcutId The shortcut to be refreshed.
119         * @param listener Who to report back to when the result is in.
120         */
121        ShortcutRefreshTask(Source source, String shortcutId, String extraData,
122                Listener listener) {
123            mSource = source;
124            mShortcutId = shortcutId;
125            mExtraData = extraData;
126            mListener = listener;
127        }
128
129        public String getName() {
130            return mSource.getName();
131        }
132
133        public void run() {
134            // TODO: Add latency tracking and logging.
135            SuggestionCursor refreshed = mSource.refreshShortcut(mShortcutId, mExtraData);
136            onShortcutRefreshed(refreshed);
137            mListener.onShortcutRefreshed(mSource, mShortcutId, refreshed);
138        }
139
140    }
141}
142