| /* |
| * Copyright (c) OSGi Alliance (2015, 2017). All Rights Reserved. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.osgi.util.converter; |
| |
| import java.lang.reflect.ParameterizedType; |
| import java.lang.reflect.Type; |
| |
| import org.osgi.annotation.versioning.ConsumerType; |
| |
| /** |
| * An object does not carry any runtime information about its generic type. |
| * However sometimes it is necessary to specify a generic type, that is the |
| * purpose of this class. It allows you to specify an generic type by defining a |
| * type T, then subclassing it. The subclass will have a reference to the super |
| * class that contains this generic information. Through reflection, we pick |
| * this reference up and return it with the getType() call. |
| * |
| * <pre> |
| * List<String> result = converter.convert(Arrays.asList(1, 2, 3)) |
| * .to(new TypeReference<List<String>>() {}); |
| * </pre> |
| * |
| * @param <T> The target type for the conversion. |
| * @author $Id$ |
| */ |
| @ConsumerType |
| public class TypeReference<T> { |
| /** |
| * A {@link TypeReference} cannot be directly instantiated. To use it, it |
| * has to be extended, typically as an anonymous inner class. |
| */ |
| protected TypeReference() {} |
| |
| /** |
| * Return the actual type of this Type Reference |
| * |
| * @return the type of this reference. |
| */ |
| public Type getType() { |
| return ((ParameterizedType) getClass().getGenericSuperclass()) |
| .getActualTypeArguments()[0]; |
| } |
| } |