TA的每日心情 | 开心 2021-3-12 23:18 |
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签到天数: 2 天 [LV.1]初来乍到
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通过反射API构造对象,并使用反射调用方式访问对象的public/private方法和字段。
package lavasoft.test;
/**
* 测试的业务类
*
* @author leizhimin 2010-5-6 20:16:10
*/
public
class MyService {
private String msg;
public MyService() {
System.out.println(
"log: 无参构造方法lavasoft.test.MyService.MyService()被调用过了!");
}
public MyService(String msg) {
System.out.println(
"log: 有参构造方法lavasoft.test.MyService.MyService()被调用过了!");
this.msg = msg;
}
public String doSomething(String person, String something) {
System.out.println(
"log: 业务方法lavasoft.test.MyService.doSomething()被调用过了!");
return person +
" is doing " + something +
"! " +
"附加消息:" + msg;
}
public String getMsg() {
System.out.println(
"log: lavasoft.test.MyService.getMsg()被调用过了!");
return msg;
}
public
void setMsg(String msg) {
System.out.println(
"log: lavasoft.test.MyService.setMsg()被调用过了!");
this.msg = msg;
}
private String doPrivate() {
System.out.println(
"log: 私有方法lavasoft.test.MyService.doPrivate()被调用过了!");
return
"私有方法doPrivate()被调用了!";
}
}
package lavasoft.test;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.*;
/**
* Java反射深度测试
*
* @author leizhimin 2010-5-6 20:26:49
*/
public
class TestReflect {
public
static
void main(String[] args)
throws NoSuchMethodException, InvocationTargetException, IllegalAccessException, InstantiationException, NoSuchFieldException {
//通过反射方式创建对象
Class clazz = MyService.
class;
MyService sv = (MyService)clazz.getConstructor().newInstance();
sv.setMsg(
"通过Class方式创建一个对象,并调用对象上的方法!");
//通过反射方式调用对象的public方法
Method m_setMsg = clazz.getMethod(
"setMsg",String.
class);
m_setMsg.invoke(sv,
"通过反射调用了sv对象上的一个方法!");
Method m_do = clazz.getMethod(
"doSomething",String.
class ,String.
class);
String re = (String)m_do.invoke(sv,
"张三" ,
"吃饭");
System.out.println(re);
//通过反射方式调用对象的private方法
Method m_doPrivate = clazz.getDeclaredMethod(
"doPrivate");
m_doPrivate.setAccessible(
true);
m_doPrivate.invoke(sv);
//通过反射方式访问对象private字段
Field f_msg = clazz.getDeclaredField(
"msg");
f_msg.setAccessible(
true);
f_msg.set(sv,
"hahahahahahahaha");
System.out.println(sv.getMsg());
}
}
log: 无参构造方法lavasoft.test.MyService.MyService()被调用过了!
log: lavasoft.test.MyService.setMsg()被调用过了!
log: lavasoft.test.MyService.setMsg()被调用过了!
log: 业务方法lavasoft.test.MyService.doSomething()被调用过了!
张三 is doing 吃饭! 附加消息:通过反射调用了sv对象上的一个方法!
log: 私有方法lavasoft.test.MyService.doPrivate()被调用过了!
log: lavasoft.test.MyService.getMsg()被调用过了!
hahahahahahahaha
Process finished with exit code 0
本文出自 “熔 岩” 博客,请务必保留此出处http://lavasoft.blog.51cto.com/62575/311484
源码下载:http://file.javaxxz.com/2014/10/29/235746250.zip |
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