1 /* 2 * Copyright (C) 2012 The Guava Authors 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.google.common.reflect; 18 19 import static com.google.common.base.Preconditions.checkArgument; 20 21 import java.lang.reflect.ParameterizedType; 22 import java.lang.reflect.Type; 23 24 /** 25 * Captures the actual type of {@code T}. 26 * 27 * @author Ben Yu 28 */ 29 abstract class TypeCapture<T> { 30 31 /** Returns the captured type. */ capture()32 final Type capture() { 33 Type superclass = getClass().getGenericSuperclass(); 34 checkArgument(superclass instanceof ParameterizedType, 35 "%s isn't parameterized", superclass); 36 return ((ParameterizedType) superclass).getActualTypeArguments()[0]; 37 } 38 } 39