1 /*
2  * Copyright 2019 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 android.view.inspector;
18 
19 import android.annotation.NonNull;
20 import android.annotation.Nullable;
21 
22 /**
23  * An inspection companion provider that finds companions as inner classes or generated code.
24  */
25 public class StaticInspectionCompanionProvider implements InspectionCompanionProvider {
26     /**
27      * The suffix used for the generated classes and inner classes
28      */
29     private static final String COMPANION_SUFFIX = "$InspectionCompanion";
30 
31     @Override
32     @Nullable
33     @SuppressWarnings("unchecked")
provide(@onNull Class<T> cls)34     public <T> InspectionCompanion<T> provide(@NonNull Class<T> cls) {
35         final String companionName = cls.getName() + COMPANION_SUFFIX;
36 
37         try {
38             final Class<InspectionCompanion<T>> companionClass =
39                     (Class<InspectionCompanion<T>>) cls.getClassLoader().loadClass(companionName);
40 
41             if (InspectionCompanion.class.isAssignableFrom(companionClass)) {
42                 return companionClass.newInstance();
43             } else {
44                 return null;
45             }
46         } catch (ClassNotFoundException e) {
47             return null;
48         } catch (IllegalAccessException e) {
49             throw new RuntimeException(e);
50         } catch (InstantiationException e) {
51             Throwable cause = e.getCause();
52             if (cause instanceof RuntimeException) throw (RuntimeException) cause;
53             if (cause instanceof Error) throw (Error) cause;
54             throw new RuntimeException(cause);
55         }
56     }
57 }
58