java反射获取泛型信息

通过反射获取泛型信息

package com.yuanyu.annandre;

import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.List;
import java.util.Map;

//通过反射获取泛型
public class Test12 {
    public void test1(Map<String,User> map, List<User> list){
        System.out.println("Test1");
    }

    public Map<String,User> test2(){
        System.out.println("Tets2");
        return null;
    }

    public static void main(String[] args) throws NoSuchMethodException {
        Method method= Test12.class.getMethod("test1", Map.class, List.class);

        Type[] genericParameterTypes = method.getGenericParameterTypes(); //获得泛型参数类型
        for (Type genericParameterType : genericParameterTypes) {
            System.out.println("#"+genericParameterType);
            if (genericParameterType instanceof ParameterizedType){
                Type[] actualTypeArguments = ((ParameterizedType) genericParameterType).getActualTypeArguments();
                for (Type actualTypeArgument : actualTypeArguments) {
                    System.out.println(actualTypeArgument);
                }
            }
        }

        method= Test12.class.getMethod("test2");
        Type genericReturnType = method.getGenericReturnType();
        if (genericReturnType instanceof ParameterizedType){
            Type[] actualTypeArguments = ((ParameterizedType) genericReturnType).getActualTypeArguments();
            for (Type actualTypeArgument : actualTypeArguments) {
                System.out.println(actualTypeArgument);
            }
        }
    }
}

程序运行结果：