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 17 package com.android.layoutlib.bridge.util; 18 19 import android.annotation.NonNull; 20 import android.annotation.Nullable; 21 22 import java.lang.reflect.InvocationTargetException; 23 import java.lang.reflect.Method; 24 25 /** 26 * Utility to convert checked Reflection exceptions to unchecked exceptions. 27 */ 28 public class ReflectionUtils { 29 30 @NonNull getMethod(@onNull Class<?> clazz, @NonNull String name, @Nullable Class<?>... params)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 @NonNull getAccessibleMethod(@onNull Class<?> clazz, @NonNull String name, @Nullable Class<?>... params)41 public static Method getAccessibleMethod(@NonNull Class<?> clazz, @NonNull String name, 42 @Nullable Class<?>... params) throws ReflectionException { 43 Method method = getMethod(clazz, name, params); 44 method.setAccessible(true); 45 46 return method; 47 } 48 49 @Nullable invoke(@onNull Method method, @Nullable Object object, @Nullable Object... args)50 public static Object invoke(@NonNull Method method, @Nullable Object object, 51 @Nullable Object... args) throws ReflectionException { 52 Exception ex; 53 try { 54 return method.invoke(object, args); 55 } catch (IllegalAccessException | InvocationTargetException e) { 56 ex = e; 57 } 58 throw new ReflectionException(ex); 59 } 60 61 /** 62 * Check if the object is an instance of a class named {@code className}. This doesn't work 63 * for interfaces. 64 */ isInstanceOf(Object object, String className)65 public static boolean isInstanceOf(Object object, String className) { 66 Class superClass = object.getClass(); 67 while (superClass != null) { 68 String name = superClass.getName(); 69 if (name.equals(className)) { 70 return true; 71 } 72 superClass = superClass.getSuperclass(); 73 } 74 return false; 75 } 76 77 @NonNull getCause(@onNull Throwable throwable)78 public static Throwable getCause(@NonNull Throwable throwable) { 79 Throwable cause = throwable.getCause(); 80 return cause == null ? throwable : cause; 81 } 82 83 /** 84 * Looks through the class hierarchy of {@code object} at runtime and returns the class matching 85 * the name {@code className}. 86 * <p> 87 * This is used when we cannot use Class.forName() since the class we want was loaded from a 88 * different ClassLoader. 89 */ 90 @NonNull getClassInstance(@onNull Object object, @NonNull String className)91 public static Class<?> getClassInstance(@NonNull Object object, @NonNull String className) { 92 Class<?> superClass = object.getClass(); 93 while (superClass != null) { 94 if (className.equals(superClass.getName())) { 95 return superClass; 96 } 97 superClass = superClass.getSuperclass(); 98 } 99 throw new RuntimeException("invalid object/classname combination."); 100 } 101 102 /** 103 * Wraps all reflection related exceptions. Created since ReflectiveOperationException was 104 * introduced in 1.7 and we are still on 1.6 105 */ 106 public static class ReflectionException extends Exception { ReflectionException()107 public ReflectionException() { 108 super(); 109 } 110 ReflectionException(String message)111 public ReflectionException(String message) { 112 super(message); 113 } 114 ReflectionException(String message, Throwable cause)115 public ReflectionException(String message, Throwable cause) { 116 super(message, cause); 117 } 118 ReflectionException(Throwable cause)119 public ReflectionException(Throwable cause) { 120 super(cause); 121 } 122 } 123 } 124