1 /*
2  * Copyright (C) 2024 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.google.android.msdl.logging
18 
19 import androidx.annotation.VisibleForTesting
20 import androidx.annotation.VisibleForTesting.Companion.PACKAGE_PRIVATE
21 import java.util.ArrayDeque
22 import java.util.Deque
23 
24 @VisibleForTesting(otherwise = PACKAGE_PRIVATE)
25 class MSDLHistoryLoggerImpl(private val maxHistorySize: Int) : MSDLHistoryLogger {
26 
27     // Use an [ArrayDequeue] with a fixed size as the history structure
28     private val history: Deque<MSDLEvent> = ArrayDeque(maxHistorySize)
29 
addEventnull30     override fun addEvent(event: MSDLEvent) {
31         // Keep the history as a FIFO structure
32         if (history.size == maxHistorySize) {
33             history.removeFirst()
34         }
35         history.addLast(event)
36     }
37 
getHistorynull38     override fun getHistory(): List<MSDLEvent> = history.toList()
39 }
40