154.-反射-利用Field赋值和获取值__

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package com.itheima.myreffect3;

import java.lang.reflect.Field;

public class RefectDemo2 {
    public static void main(String[] args) throws ClassNotFoundException, NoSuchFieldException, InstantiationException, IllegalAccessException {
        //method1();
        method2();
    }

    private static void method2() throws ClassNotFoundException, NoSuchFieldException, InstantiationException, IllegalAccessException {
        Class clazz = Class.forName("com.itheima.myreffect3.Student");
        Field field = clazz.getDeclaredField("money");
        field.setAccessible(true);
        Student student = (Student) clazz.newInstance();
        Object o = field.get(student);
        System.out.println(o);
    }

    private static void method1() throws ClassNotFoundException, NoSuchFieldException, InstantiationException, IllegalAccessException {
        Class clazz = Class.forName("com.itheima.myreffect3.Student");
        Field field = clazz.getField("name");
        Student stuent = (Student) clazz.newInstance();
        field.set(stuent,"zhangsan");
        System.out.println(stuent);
    }
}

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package com.itheima.myreffect3;

public class Student {
    public String name;
    public int age;
    public String gernder;
    private int money=300;

    @Override
    public String toString() {
        return "Student{" +
                "name='" + name + ''' +
                ", age=" + age +
                ", gernder='" + gernder + ''' +
                ", money=" + money +
                '}';
    }
}