成员变量的反射实例

package com.demo.day01;

import java.lang.reflect.Field;


public class ReflectPoint {
	
	private int x;
	public int y;
	public String str1 = "ball";
	public String str2 = "basketball";
	public String str3 ="itcast";
	
	@Override
	public String toString() {
		return "ReflectPoint [str1=" + str1 + ", str2=" + str2 + ", str3="
				+ str3 + "]";
	}

	
	public static void main(String[] args) throws Exception {
		ReflectPoint rp1 = new ReflectPoint();
		changeStringValue(rp1);
		
	}


	private static void changeStringValue(Object obj) throws IllegalArgumentException, IllegalAccessException {
		//obj.getClass()：获得字节码
		//.getFields()：获得所有字段
		//此时fields中只有四个字节码对象，（x是私有属性）
		Field[] fields = obj.getClass().getFields();
		for(Field field:fields){
			//获取字段类型（属性类型）比较类型用== 
			if(field.getType() == String.class){
				String oldVal = (String) field.get(obj);
				String newValue = oldVal.replace("b", "a");
				field.set(obj, newValue);
			}
		}
		
	}
	
	
	
	
	
	
	
	
	
	
	
	
	
	

}