ReflectionUtils.java revision ccbc11770397888cf7780925bb4c7cf1d2f2f80e 
1/*
2 * Copyright (C) 2015 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
17package com.android.layoutlib.bridge.util;
18
19import android.annotation.NonNull;
20import android.annotation.Nullable;
21
22import java.lang.reflect.InvocationTargetException;
23import java.lang.reflect.Method;
24
25/**
26 * Utility to convert checked Reflection exceptions to unchecked exceptions.
27 */
28public class ReflectionUtils {
29
30    @NonNull
31    public static Method getMethod(@NonNull Class<?> clazz, @NonNull String name,
32            @Nullable Class<?>... params) throws ReflectionException {
33        try {
34            return clazz.getMethod(name, params);
35        } catch (NoSuchMethodException e) {
36            throw new ReflectionException(e);
37        }
38    }
39
40    @Nullable
41    public static Object invoke(@NonNull Method method, @Nullable Object object,
42            @Nullable Object... args) throws ReflectionException {
43        Exception ex;
44        try {
45            return method.invoke(object, args);
46        } catch (IllegalAccessException e) {
47            ex = e;
48        } catch (InvocationTargetException e) {
49            ex = e;
50        }
51        throw new ReflectionException(ex);
52    }
53
54    /**
55     * Check if the object is an instance of a class named {@code className}. This doesn't work
56     * for interfaces.
57     */
58    public static boolean isInstanceOf(Object object, String className) {
59        Class superClass = object.getClass();
60        while (superClass != null) {
61            String name = superClass.getName();
62            if (name.equals(className)) {
63                return true;
64            }
65            superClass = superClass.getSuperclass();
66        }
67        return false;
68    }
69
70    @NonNull
71    public static Throwable getCause(@NonNull Throwable throwable) {
72        Throwable cause = throwable.getCause();
73        return cause == null ? throwable : cause;
74    }
75
76    /**
77     * Wraps all reflection related exceptions. Created since ReflectiveOperationException was
78     * introduced in 1.7 and we are still on 1.6
79     */
80    public static class ReflectionException extends Exception {
81        public ReflectionException() {
82            super();
83        }
84
85        public ReflectionException(String message) {
86            super(message);
87        }
88
89        public ReflectionException(String message, Throwable cause) {
90            super(message, cause);
91        }
92
93        public ReflectionException(Throwable cause) {
94            super(cause);
95        }
96    }
97}
98