Java-反射-调用泛型信息

拼搏现实的明天。 2024-04-20 08:07 99阅读 0赞

代码：

package com.cdmt.java.annotation.historyhandler;
    
    import java.lang.reflect.Method;
    import java.lang.reflect.ParameterizedType;
    import java.lang.reflect.Type;
    import java.util.List;
    import java.util.Map;
    
    /**
     * 反射调用泛型信息
     **/
    
    //通过反射获取泛型
    public class Test10 {
        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 {
            Method method = Test10.class.getMethod("test01", Map.class, List.class);
            Type[] getGenericParameterTypes = method.getGenericParameterTypes();
            for(Type getGenericParameterType : getGenericParameterTypes){
                System.out.println("#" + getGenericParameterType);
                if(getGenericParameterType instanceof ParameterizedType){
                    Type[] actualTypeArguments = ((ParameterizedType) getGenericParameterType).getActualTypeArguments();
                    for(Type actualTypeArgument : actualTypeArguments){
                        System.out.println(actualTypeArgument);
                    }
                }
            }
    
            Method method1 = Test10.class.getMethod("test02", null);
            Type genericReturnType = method1.getGenericReturnType();
            if(genericReturnType instanceof ParameterizedType){
                    Type[] actualTypeArguments = ((ParameterizedType) genericReturnType).getActualTypeArguments();
                    for(Type actualTypeArgument : actualTypeArguments){
                        System.out.println(actualTypeArgument);
                    }
                }
            }
    }

结果：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9odWFuZ2hhaXRhby5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9odWFuZ2hhaXRhby5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/18/a9c7400f2de746bbb037f984e2dcedc7.png