1 /*
2  * Copyright (C) 2020 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.eventlib;
18 
19 import java.time.Duration;
20 import java.time.Instant;
21 
22 
23 /** Interface for interacting with a local or remote {@link Event} store. */
24 interface EventQuerier<E extends Event> {
25     /**
26      * Gets the next unseen {@link Event} which wasn't logged before {@code earliestLogTime},
27      * or blocks until one is logged.
28      *
29      * <p>After {@code timeout}, null will be returned.
30      */
poll(Instant earliestLogTime, Duration timeout)31     E poll(Instant earliestLogTime, Duration timeout);
32 }
33