Timeouts.java revision 646fa3d6eaea71fb4c3270fde1a30eeb7c5e4288 
1/*
2 * Copyright (C) 2014 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.server.telecom;
18
19import android.content.ContentResolver;
20import android.provider.Settings;
21
22/**
23 * A helper class which serves only to make it easier to lookup timeout values. This class should
24 * never be instantiated, and only accessed through the {@link #get(String, long)} method.
25 *
26 * These methods are safe to call from any thread, including the UI thread.
27 */
28public final class Timeouts {
29    /** A prefix to use for all keys so to not clobber the global namespace. */
30    private static final String PREFIX = "telecom.";
31
32    private Timeouts() {}
33
34    /**
35     * Returns the timeout value from Settings or the default value if it hasn't been changed. This
36     * method is safe to call from any thread, including the UI thread.
37     *
38     * @param contentResolver The content resolved.
39     * @param key Settings key to retrieve.
40     * @param defaultValue Default value, in milliseconds.
41     * @return The timeout value from Settings or the default value if it hasn't been changed.
42     */
43    private static long get(ContentResolver contentResolver, String key, long defaultValue) {
44        return Settings.Secure.getLong(contentResolver, PREFIX + key, defaultValue);
45    }
46
47    /**
48     * Returns the longest period, in milliseconds, to wait for the query for direct-to-voicemail
49     * to complete. If the query goes beyond this timeout, the incoming call screen is shown to the
50     * user.
51     */
52    public static long getDirectToVoicemailMillis(ContentResolver contentResolver) {
53        return get(contentResolver, "direct_to_voicemail_ms", 500L);
54    }
55
56    /**
57     * Returns the amount of time to wait before disconnecting a call that was canceled via
58     * NEW_OUTGOING_CALL broadcast. This timeout allows apps which repost the call using a gateway
59     * to reuse the existing call, preventing the call from causing a start->end->start jank in the
60     * in-call UI.
61     */
62    public static long getNewOutgoingCallCancelMillis(ContentResolver contentResolver) {
63        return get(contentResolver, "new_outgoing_call_cancel_ms", 300L);
64    }
65
66    /**
67     * Returns the amount of time to play each DTMF tone after post dial continue.
68     * This timeout allows the current tone to play for a certain amount of time before either being
69     * interrupted by the next tone or terminated.
70     */
71    public static long getDelayBetweenDtmfTonesMillis(ContentResolver contentResolver) {
72        return get(contentResolver, "delay_between_dtmf_tones_ms", 300L);
73    }
74
75    /**
76     * Returns the amount of time to wait for an emergency call to be placed before routing to
77     * a different call service. A value of 0 or less means no timeout should be used.
78     */
79    public static long getEmergencyCallTimeoutMillis(ContentResolver contentResolver) {
80        return get(contentResolver, "emergency_call_timeout_millis", 25000L /* 25 seconds */);
81    }
82
83    /**
84     * Returns the amount of time to wait for an emergency call to be placed before routing to
85     * a different call service. This timeout is used only when the radio is powered off (for
86     * example in airplane mode). A value of 0 or less means no timeout should be used.
87     */
88    public static long getEmergencyCallTimeoutRadioOffMillis(ContentResolver contentResolver) {
89        return get(contentResolver, "emergency_call_timeout_radio_off_millis",
90                60000L /* 1 minute */);
91    }
92}
93