1 /*
2  * Copyright (C) 2022 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.telephony.qns;
18 
19 import android.os.Handler;
20 import android.os.Message;
21 
22 import java.lang.ref.WeakReference;
23 
24 /** @hide */
25 class QnsRegistrant {
26     protected WeakReference<Handler> mRefH;
27     protected int mWhat;
28     protected Object mUserObj;
29 
QnsRegistrant(Handler h, int what, Object obj)30     QnsRegistrant(Handler h, int what, Object obj) {
31         mRefH = new WeakReference<>(h);
32         mWhat = what;
33         mUserObj = obj;
34     }
35 
36     /** Clear registrant. */
clear()37     void clear() {
38         mRefH = null;
39         mUserObj = null;
40     }
41 
42     /**
43      * notify result
44      *
45      * @param result Object to notify
46      */
notifyResult(Object result)47     void notifyResult(Object result) {
48         internalNotifyRegistrant(result, null);
49     }
50 
51     /**
52      * notify registrant
53      *
54      * @param ar QnsAsyncResult to notify
55      */
notifyRegistrant(QnsAsyncResult ar)56     void notifyRegistrant(QnsAsyncResult ar) {
57         internalNotifyRegistrant(ar.mResult, ar.mException);
58     }
59 
internalNotifyRegistrant(Object result, Throwable exception)60     protected void internalNotifyRegistrant(Object result, Throwable exception) {
61         Handler h = getHandler();
62 
63         if (h == null) {
64             clear();
65         } else {
66             Message msg = Message.obtain();
67 
68             msg.what = mWhat;
69             msg.obj = new QnsAsyncResult(mUserObj, result, exception);
70             h.sendMessage(msg);
71         }
72     }
73 
74     /**
75      * get a handler.
76      *
77      * @return Handler
78      */
getHandler()79     Handler getHandler() {
80         if (mRefH == null) {
81             return null;
82         }
83 
84         return mRefH.get();
85     }
86 }
87