使用javassist框架進行動態的更改Class類

@Test
	public  void changeClass() throws Exception {
		
		ClassPool pool = ClassPool.getDefault();
		//獲取一個Student類的CtClass對象
		CtClass ctClass = pool.get("com.javassist.domain.Student");
		
		//為ctClass設置一個父類
		ctClass.setSuperclass(pool.get("com.javassist.domain.Person"));
		//為cTclass對象添加一個屬性name
		ctClass.addField(CtField.make("private String name;", ctClass));
		ctClass.addMethod(CtMethod.make("public void setName(String name){this.name = name;}", ctClass));
		ctClass.addMethod(CtMethod.make("public String getName(){return this.name;}", ctClass));
		
		//獲取ctClass對象對應的Class對象student
		Class student = ctClass.toClass();
		//對student類進行內省，得到對象BeanInfo
		BeanInfo beanInfo = Introspector.getBeanInfo(student, Object.class);
		//獲取beanInfo的方法描述對象
		MethodDescriptor[] descriptors = beanInfo.getMethodDescriptors();
		
		for (int i = 0; i < descriptors.length; i++) {
			System.out.println(descriptors[i].getName());
		}
		System.out.println(descriptors.length);
		
		PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors();
		for (int i = 0; i < propertyDescriptors.length; i++) {
			System.out.println(propertyDescriptors[i].getDisplayName());
		}
	}