内省Introspector 和BeanUtils 工具对反射属性的包装(简单的不是一点点哦)

	public void fun2() throws Exception
	{
		//通过反射和dom4j实例化id=stu1的对象,并输出
		SAXReader reader = new SAXReader();                
		Document   document = reader.read(this.getClass().getResourceAsStream("/beans.xml"));

		String xpath="/beans/bean[@id=\"stu1\"]";
		
		Element element=(Element) document.selectSingleNode(xpath);
		
		Class clazz=Class.forName(element.attributeValue("className"));
		Student student=(Student) clazz.newInstance();
		List<Element> els=element.elements();
		System.out.println(student);
		//根据变量名获取变量类型
		2");
		for (Element e : els) {
			Field f=clazz.getDeclaredField(e.attributeValue("name"));
		
			String sClassString=f.getType().getName();
			
			Method method=clazz.getMethod("set"+captureName(f.getName()),Class.forName(sClassString));
			method.invoke(student, e.attributeValue("value"));
			
		}
		System.out.println(student);
	}

　　使用内省

	public void neixing() throws Exception
	{
		BeanInfo info = Introspector.getBeanInfo(Student.class);
	
		//获取某个属性的描述器
		PropertyDescriptor pDescriptor=new PropertyDescriptor("name", Student.class);
		//获得某个类的所有描述器 
		//		PropertyDescriptor[] pds = info.getPropertyDescriptors();
		
//		BeanUtils.getP
		Method method=pDescriptor.getReadMethod();
		System.out.println(method.getName());
		
		//BeanUtils更方便
//		BeanUtils.getProperty(bean, name, value)
//		BeanUtils.setProperty(bean, name, value)

	}

　　获得描述器后 getReadMethod(),getSetMethod() 就是对 Method method=clazz.getMethod("set"+captureName(f.getName()),Class.forName(sClassString));极大简化

 

BeanUtils

	public void fun3() throws Exception
	{
		SAXReader reader = new SAXReader();                
		Document   document = reader.read(this.getClass().getResourceAsStream("/beans.xml"));
		String xpath="/beans/bean[@id=\"stu1\"]";
		Element element=(Element) document.selectSingleNode(xpath);
		Class clazz=Class.forName(element.attributeValue("className"));
		Student student=(Student) clazz.newInstance();
		List<Element> els=element.elements();
		System.out.println(student);
		for (Element e : els) {
			Field f=clazz.getDeclaredField(e.attributeValue("name"));
			BeanUtils.setProperty(student, f.getName(), e.attributeValue("value"));
		}
		System.out.println(student);
	}

　beanUtils.getProperty

beanUtils.setPropert 

　　简化了getMethod() ,和invoke()连个方法

使反射获得属性描述器并执行赋值/取值更方便