反射_4.案例：使用反射替换对象所有字符串值

Posted 2020-10-21 dingjm01

package com.day2;

import java.lang.reflect.Field;

public class T4_ReflectReplaceString {
    public static void main(String[] args) {
        Demo demo1 = new Demo();
        try {
            //调用该方法
            reflectReplaceString(demo1);
            System.out.println(demo1);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 通过反射替换字符串的所有b
     * 
     * @param demo
     *            该对象
     */
    public static void reflectReplaceString(Demo demo) throws Exception {
        // 1.得到该对象的类对象
        Class c = demo.getClass();
        // 2.获取所有属性对象（包括私有属性）
        Field[] fields = c.getDeclaredFields();
        // 3.遍历
        for (Field field : fields) {
            // 4.设置可以访问私有属性
            field.setAccessible(true);
            // 5.获取demo的属性值
            String oldVal = (String) field.get(demo);
            // 6.替换所有b字符为a字符
            String newVal = oldVal.replace("b", "a");
            // 7.设置demo的属性值为newVal
            field.set(demo, newVal);
        }

    }
}

Demo.java

package com.day2;

public class Demo {
    private String name = "abcdefg";
    private String sex = "boy";
    private String wife = "Bob";

    @Override
    public String toString() {
        return "Demo [name=" + name + ", sex=" + sex + ", wife=" + wife + "]";
    }

}

控制台输出：

　　Demo [name=aacdefg, sex=aoy, wife=Boa]