获取父类的泛型-获取当前类实现的接口

1.获取运行时类的父类及父类的泛型

public class refletTest {
    
    @Test
    public void test2(){
        Class clazz = Person.class;
        Class superclass = clazz.getSuperclass();
        System.out.println(superclass);
    }

    
    @Test
    public void test3(){
        Class clazz = Person.class;
        Type genericSuperclass = clazz.getGenericSuperclass();
        System.out.println(genericSuperclass);
    }

    
    @Test
    public void test4(){
        Class clazz = Person.class;
        Type genericSuperclass = clazz.getGenericSuperclass();
        //如果 genericSuperclass 确定是带泛型的父类，强转为参数类型 ParameterizedType 方便调用后续的方法
        //paramType 泛型参数
        ParameterizedType paramType = (ParameterizedType) genericSuperclass;
        //paramType.getActualTypeArguments() 获取实际类型参数/获取泛型类型
        Type[] actualTypeArguments = paramType.getActualTypeArguments();
        //因为是数组，如果只有一个泛型参数就按 index=0 来获取 
//        System.out.println(actualTypeArguments[0].getTypeName());//java.uitl.String
        System.out.println(((Class)actualTypeArguments[0]).getName());
    }
}

2.获取运行时类的接口、所在包、注解

public class Test {
    
    @Test
    public void test5(){
        Class clazz = Person.class;

        Class[] interfaces = clazz.getInterfaces();
        for(Class c : interfaces){
            System.out.println(c);
        }
        System.out.println("++++++++++++++++++++++");
       
        //获取运行时类的父类实现的接口
        Class[] interfaces1 = clazz.getSuperclass().getInterfaces();
        for(Class c : interfaces1){
            System.out.println(c);
        }
    }

    
    @Test
    public void test6(){
        Class clazz = Person.class;
        Package pack = clazz.getPackage();
        System.out.println(pack);
    }

    
    @Test
    public void test7(){
        Class clazz = Person.class;
        Annotation[] annotations = clazz.getAnnotations();
        for(Annotation annos : annotations){
            System.out.println(annos);
        }
    }
}

反射-获取运行时类的结构