1 /*
2  * Copyright (C) 2018 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.internal.infra;
18 
19 import android.annotation.NonNull;
20 import android.content.ComponentName;
21 import android.content.Context;
22 import android.os.Handler;
23 import android.os.IInterface;
24 import android.util.Slog;
25 
26 import java.io.PrintWriter;
27 
28 /**
29  * Base class representing a remote service that can have only one pending requests while not bound.
30  *
31  * <p>If another request is received while not bound, the previous one will be canceled.
32  *
33  * @param <S> the concrete remote service class
34  * @param <I> the interface of the binder service
35  *
36  * @hide
37  */
38 public abstract class AbstractSinglePendingRequestRemoteService<S
39         extends AbstractSinglePendingRequestRemoteService<S, I>, I extends IInterface>
40         extends AbstractRemoteService<S, I> {
41 
42     protected BasePendingRequest<S, I> mPendingRequest;
43 
AbstractSinglePendingRequestRemoteService(@onNull Context context, @NonNull String serviceInterface, @NonNull ComponentName componentName, int userId, @NonNull VultureCallback<S> callback, @NonNull Handler handler, int bindingFlags, boolean verbose)44     public AbstractSinglePendingRequestRemoteService(@NonNull Context context,
45             @NonNull String serviceInterface, @NonNull ComponentName componentName, int userId,
46             @NonNull VultureCallback<S> callback, @NonNull Handler handler,
47             int bindingFlags, boolean verbose) {
48         super(context, serviceInterface, componentName, userId, callback, handler, bindingFlags,
49                 verbose);
50     }
51 
52     @Override // from AbstractRemoteService
handlePendingRequests()53     void handlePendingRequests() {
54         if (mPendingRequest != null) {
55             final BasePendingRequest<S, I> pendingRequest = mPendingRequest;
56             mPendingRequest = null;
57             handlePendingRequest(pendingRequest);
58         }
59     }
60 
61     @Override // from AbstractRemoteService
handleOnDestroy()62     protected void handleOnDestroy() {
63         handleCancelPendingRequest();
64     }
65 
handleCancelPendingRequest()66     protected BasePendingRequest<S, I> handleCancelPendingRequest() {
67         BasePendingRequest<S, I> pendingRequest = mPendingRequest;
68         if (pendingRequest != null) {
69             pendingRequest.cancel();
70             mPendingRequest = null;
71         }
72         return pendingRequest;
73     }
74 
75     @Override // from AbstractRemoteService
handleBindFailure()76     void handleBindFailure() {
77         if (mPendingRequest != null) {
78             if (mVerbose) Slog.v(mTag, "Sending failure to " + mPendingRequest);
79             mPendingRequest.onFailed();
80             mPendingRequest = null;
81         }
82     }
83 
84     @Override // from AbstractRemoteService
dump(@onNull String prefix, @NonNull PrintWriter pw)85     public void dump(@NonNull String prefix, @NonNull PrintWriter pw) {
86         super.dump(prefix, pw);
87         pw.append(prefix).append("hasPendingRequest=")
88                 .append(String.valueOf(mPendingRequest != null)).println();
89     }
90 
91     @Override // from AbstractRemoteService
handlePendingRequestWhileUnBound(@onNull BasePendingRequest<S, I> pendingRequest)92     void handlePendingRequestWhileUnBound(@NonNull BasePendingRequest<S, I> pendingRequest) {
93         if (mPendingRequest != null) {
94             if (mVerbose) {
95                 Slog.v(mTag, "handlePendingRequestWhileUnBound(): cancelling " + mPendingRequest
96                         + " to handle " + pendingRequest);
97             }
98             mPendingRequest.cancel();
99         }
100         mPendingRequest = pendingRequest;
101     }
102 }
103