1 /*
2  * Copyright (C) 2023 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.launcher3.logging
18 
19 import androidx.annotation.MainThread
20 
21 /** Interface to log launcher startup latency metrics. */
22 interface StartupLatencyLogger {
23 
lognull24     @MainThread fun log(): StartupLatencyLogger = this
25 
26     @MainThread fun logWorkspaceLoadStartTime(): StartupLatencyLogger = this
27 
28     /**
29      * Log size of workspace. Larger number of workspace items (icons, folders, widgets) means
30      * longer latency to initialize workspace.
31      */
32     @MainThread fun logCardinality(cardinality: Int): StartupLatencyLogger = this
33 
34     @MainThread
35     fun logStart(event: StatsLogManager.LauncherLatencyEvent): StartupLatencyLogger = this
36 
37     @MainThread
38     fun logStart(
39         event: StatsLogManager.LauncherLatencyEvent,
40         startTimeMs: Long
41     ): StartupLatencyLogger = this
42 
43     @MainThread fun logEnd(event: StatsLogManager.LauncherLatencyEvent): StartupLatencyLogger = this
44 
45     @MainThread
46     fun logEnd(event: StatsLogManager.LauncherLatencyEvent, endTimeMs: Long): StartupLatencyLogger =
47         this
48 
49     @MainThread fun reset()
50 
51     companion object {
52         val NO_OP: StartupLatencyLogger =
53             object : StartupLatencyLogger {
54                 override fun reset() {}
55             }
56     }
57 }
58