通过反射创建构造函数为private修饰的对象

CarFactory instance = CarFactory.getInstance();
Class<?> aClass = Class.forName("com.jsdc.tianqi.danli.CarFactory");//这个CarFacotry是一个单例，构造方法private
Constructor<?> declaredConstructor = aClass.getDeclaredConstructor();
declaredConstructor.setAccessible(true);//这里很重要，设置为true 
Object o = declaredConstructor.newInstance();