java求大神编个小程序

public static void fun(Object obj) {
System.out.println("类名: "+obj.getClass());
Method[] methods = obj.getClass().getDeclaredMethods();
System.out.println("不包括从Object继承的方法所有方法:");
for(Method method : methods) {
System.out.println(method.getName());
}
Field[] fields = obj.getClass().getDeclaredFields();
System.out.println("所有字段:");
for(Field field : fields) {
System.out.println(field.getName());
}
}
}
class Person {
private String name;
private int age;

public Person() {
new Person("ss",3);
}

private Person(String name, int age) {
this.name = name;
this.age = age;
}

public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}

构造方法楼主可以去差帮助文档