通過反射來獲取泛型的參數以及返回值（不是很懂）

反射獲取泛型有下面的方法
1.從方法中獲取泛型參數列表
Type[] genericParameterTypes = method.getGenericParameterTypes ();
2.

import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.List;
import java.util.Map;
public class Test08 {
    public void test01(Map<String,User> map, List<User> list){
        System.out.println ("test01");
    }
    public Map<String,User> test02(){
        System.out.println ("test02");
        return null;
    }
    public static void main(String[] args) throws NoSuchMethodException {
        //首先獲取test01方法
        Method method = Test08.class.getMethod ("test01",Map.class,List.class);
        //將方法的泛型參數類型存儲在Type類型數組，type類型可以存儲所有的java類型
        Type[] genericParameterTypes = method.getGenericParameterTypes ();
        for (Type genericParameterType : genericParameterTypes) {
            //獲取泛型及其中參數
            System.out.println ("##"+genericParameterType);
            //
            if(genericParameterType instanceof ParameterizedType){
                Type[] actuallyTypeArguments = ((ParameterizedType)genericParameterType).getActualTypeArguments();
                for (Type actuallyTypeArgument : actuallyTypeArguments) {
                    System.out.println (actuallyTypeArgument);
                }
            }
        }
        System.out.println ("--------------------------------");
        method = Test08.class.getMethod ("test02",null);
        Type genericReturnType = method.getGenericReturnType ();
        if(genericReturnType instanceof ParameterizedType){
            Type[] actuallyTypeArguments = ((ParameterizedType)genericReturnType).getActualTypeArguments();
            for (Type actuallyTypeArgument : actuallyTypeArguments) {
                System.out.println (actuallyTypeArgument);
            }
        }

    }
}
結果：
##java.util.Map<java.lang.String, Reflection.User>
class java.lang.String
class Reflection.User
##java.util.List<Reflection.User>
class Reflection.User
--------------------------------
class java.lang.String
class Reflection.User