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.systemui.util.annotations; 18 19 import static java.lang.annotation.ElementType.TYPE; 20 21 import java.lang.annotation.Retention; 22 import java.lang.annotation.RetentionPolicy; 23 import java.lang.annotation.Target; 24 25 /** 26 * Descriptive annotation for clearly tagging callback types that are weakly 27 * referenced during registration. 28 * 29 * This is useful in providing hints to Proguard about certain fields that 30 * should be kept to preserve strong references. 31 */ 32 @Retention(RetentionPolicy.CLASS) 33 @Target({TYPE}) 34 public @interface WeaklyReferencedCallback {} 35