1 /*
2  * Copyright (C) 2019 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.server.power;
18 
19 import android.annotation.NonNull;
20 import android.annotation.Nullable;
21 import android.os.SystemProperties;
22 
23 import com.android.internal.annotations.VisibleForTesting;
24 
25 /**
26  * Wrapper interface to access {@link SystemProperties}.
27  *
28  * @hide
29  */
30 @VisibleForTesting
31 interface SystemPropertiesWrapper {
32     /**
33      * Get the String value for the given {@code key}.
34      *
35      * @param key the key to lookup
36      * @param def the default value in case the property is not set or empty
37      * @return if the {@code key} isn't found, return {@code def} if it isn't null, or an empty
38      * string otherwise
39      */
40     @NonNull
get(@onNull String key, @Nullable String def)41     String get(@NonNull String key, @Nullable String def);
42 
43     /**
44      * Set the value for the given {@code key} to {@code val}.
45      *
46      * @throws IllegalArgumentException if the {@code val} exceeds 91 characters
47      * @throws RuntimeException if the property cannot be set, for example, if it was blocked by
48      * SELinux. libc will log the underlying reason.
49      */
set(@onNull String key, @Nullable String val)50     void set(@NonNull String key, @Nullable String val);
51 }
52