1 /*
2  * Copyright (C) 2017 Google Inc.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License"); you may not
5  * use this file except in compliance with the License. You may obtain a copy of
6  * 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, WITHOUT
12  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13  * License for the specific language governing permissions and limitations under
14  * the License.
15  */
16 
17 package com.google.android.mobly.snippet.rpc;
18 
19 import java.lang.annotation.Documented;
20 import java.lang.annotation.ElementType;
21 import java.lang.annotation.Retention;
22 import java.lang.annotation.RetentionPolicy;
23 import java.lang.annotation.Target;
24 
25 /**
26  * The {@link AsyncRpc} annotation is used to annotate server-side implementations of RPCs that
27  * trigger asynchronous events. This behaves generally the same as {@link Rpc}, but methods that are
28  * annotated with {@link AsyncRpc} are expected to take the extra parameter which is the ID to use
29  * when posting async events.
30  *
31  * <p>Sample Usage:
32  *
33  * <pre>{@code
34  * {@literal @}AsyncRpc(description = "An example showing the usage of AsyncRpc")
35  * public void doSomethingAsync(String callbackId, ...) {
36  *     // start some async operation and post a Snippet Event object with the given callbackId.
37  * }
38  * }</pre>
39  *
40  * AsyncRpc methods can still return serializable values, which will be transported in the regular
41  * return value field of the Rpc protocol.
42  */
43 @Retention(RetentionPolicy.RUNTIME)
44 @Target(ElementType.METHOD)
45 @Documented
46 public @interface AsyncRpc {
47     /** Returns brief description of the function. Should be limited to one or two sentences. */
description()48     String description();
49 }
50