1 /*
2  * Copyright (C) 2016 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.documentsui.base;
18 
19 /**
20  * A functional interface that handles an event and returns a boolean to indicate if the event
21  * is consumed.
22  */
23 @FunctionalInterface
24 public interface EventHandler<T> {
accept(T event)25     boolean accept(T event);
26 
createStub(boolean reply)27     public static <T> EventHandler<T> createStub(boolean reply) {
28         return new Stub<T>(reply);
29     }
30 
31     public static final class Stub<T> implements EventHandler<T> {
32 
33         private boolean mReply;
34 
Stub(boolean reply)35         private Stub(boolean reply) {
36             mReply = reply;}
37 
38         @Override
accept(T event)39         public boolean accept(T event) {
40             return mReply;
41         }
42 
43     }
44 }