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本篇我们来一起看一下Spring Framework泛型集合类型 GenericCollectionTypeResolver，这里我总结了以下内容：

* 核心 API - org.springframework.core.GenericCollectionTypeResolver
	* 版本支持:[2.0 , 4.3]
	* 替换实现:org.springframework.core.ResolvableType
	* 处理 Collection 相关
		* getCollection*Type
	* 处理 Map 相关
		* getMapKey*Type
		* getMapValue*Type

接下来我们就通过实战的方式一起实践一下：

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.eleven.thinking.in.spring.generic;

import org.springframework.core.GenericCollectionTypeResolver;

import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.List;

/**
 * {@link GenericCollectionTypeResolver} 示例
 *
 * @author <a href="mailto:[email protected]">eleven</a>
 * @see GenericCollectionTypeResolver
 * @since
 */
public class GenericCollectionTypeResolverDemo {

    private static StringList stringList;

    private static List<String> strings;

    public static void main(String[] args) throws Exception {

        // StringList extends ArrayList<String> 具体化
        // getCollectionType 返回具体化泛型参数类型集合的成员类型 = String
        System.out.println(GenericCollectionTypeResolver.getCollectionType(StringList.class));

        System.out.println(GenericCollectionTypeResolver.getCollectionType(ArrayList.class));

        // 获取字段
        Field field = GenericCollectionTypeResolverDemo.class.getDeclaredField("stringList");
        System.out.println(GenericCollectionTypeResolver.getCollectionFieldType(field));

        field = GenericCollectionTypeResolverDemo.class.getDeclaredField("strings");
        System.out.println(GenericCollectionTypeResolver.getCollectionFieldType(field));
    }
}