屬性的概念

不只是字段，而是其get set 方法

且該get方法有返回值的稱為屬性，繼承Object類的getClass方法

package com.swift.demo1;

public class Person {
    String name;
    int age;
    String password;
    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;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    public String getAd() {//這個算一個屬性，雖讓沒有字段，但如果沒有返回值不算一個屬性
 

        return "getAd.....";
    }
}

屬性個數

package com.swift.demo1;

import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;

import org.junit.jupiter.api.Test;

public class TestIntro {
    @Test
    public void test1() throws Exception {
        BeanInfo info
 
=Introspector.getBeanInfo(Person.class);
        PropertyDescriptor[] pds=info.getPropertyDescriptors();
        for(PropertyDescriptor des:pds) {
            System.out.println(des.getName());
        }
    }
}

阻止父類的getClass屬性用

package com.swift.demo1;

import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;

import org.junit.jupiter.api.Test;

public class TestIntro {
    @Test
    public void test1() throws Exception {
        BeanInfo info=Introspector.getBeanInfo(Person.class,Object.class);
        PropertyDescriptor[] pds=info.getPropertyDescriptors();
        for(PropertyDescriptor des:pds) {
            System.out.println(des.getName());
        }
    }
}

java內省 introspector