【通过反射获取成员变量并使用】

package com.yjf.esupplier.common.test;

import java.lang.reflect.Constructor;
import java.lang.reflect.Field;

/**
 * @author shusheng
 * @description 通过反射获取成员变量并使用
 * @Email shusheng@yiji.com
 * @date 2019/1/5 16:37
 */
public class ReflectDemo2 {

    public static void main(String[] args) throws Exception {
        // 获取字节码文件对象
        Class c = Class.forName("com.yjf.esupplier.common.test.Person");
        // 只能获取公共的成员变量
        Field[] fields1 = c.getFields();
        for (Field field : fields1) {
            System.out.println(field);
        }
        System.out.println("-----------------------------------------");
        // 获取所有的成员变量
        Field[] fields2 = c.getDeclaredFields();
        for (Field field : fields2) {
            System.out.println(field);
        }

        // 通过无参构造方法创建对象
        Constructor con = c.getConstructor();
        Object obj = con.newInstance();
        System.out.println(obj);

        // 获取单个的成员变量
        // 获取address并对其赋值
        Field addressField = c.getField("address");
        // 给obj对象的addressField 字段设置值为"北京"
        addressField.set(obj, "北京");
        System.out.println(obj);

        // 获取name并对其赋值
        Field nameField = c.getDeclaredField("name");
        nameField.setAccessible(true);
        nameField.set(obj, "林青霞");
        System.out.println(obj);

        // 获取age并对其赋值
        Field ageField = c.getDeclaredField("age");
        ageField.setAccessible(true);
        ageField.set(obj, 27);
        System.out.println(obj);
    }

}

 

package com.yjf.esupplier.common.test;

/**
 * @author shusheng
 * @description
 * @Email shusheng@yiji.com
 * @date 2018/12/29 13:42
 */
public class Person {

        private String name;
        int age;
        public String address;

        public Person() {
        }

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

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

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

        public void show() {
            System.out.println("show方法的输出");
        }

        public void method(String s) {
            System.out.println("method方法的输出： " + s);
        }

        public String getString(String s, int i) {
            return s + "---" + i;
        }

        private void function() {
            System.out.println("function方法的输出");
        }

        @Override
        public String toString() {
            return "Person [name=" + name + ", age=" + age + ", address="
                    + address
                    + "]";
        }

}