java反射机制最基本实例

package com.nemo.reflect;

import java.lang.reflect.Field;
import java.lang.reflect.Method;

public class User {
    public String name;
    public String passwd;
	
    public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPasswd() {
		return passwd;
	}
	public void setPasswd(String passwd) {
		this.passwd = passwd;
	}
     
   public static void testFields() throws Exception{
	   Class cls = Class.forName("com.nemo.reflect.User");
	   Object ob = cls.newInstance();
	   //获取所有字段
	   Field[] fields = cls.getDeclaredFields();
	   for(Field field:fields){
		   String fieldName = field.getName();
		   //根据方法名和形式参数获取method,new Class[]{}是形参数组
		   Method method = cls.getDeclaredMethod("set"
					+ fieldName.substring(0, 1).toUpperCase()
					+ fieldName.substring(1), new Class[] { String.class });
		   //请求调用method
		   method.invoke(ob, new String[]{"love"});
	   }
	  //获取所有方法
	  Method[] methods = cls.getMethods();
	  for(Method method:methods){
		  //执行get方法
		  if(method.getName().startsWith("get")){
			  System.out.println(method.getName()+"的值是:"+method.invoke(ob, null));
		  }
	  }
	   
   }
   
   public static void main(String[] args) throws Exception {
	   User.testFields();
}
}

执行结果:

getName的值是:love
getPasswd的值是:love
getClass的值是:class com.nemo.reflect.User