如何使用java中的反射创建新实例

I have a quick question. How do I create a new instance with passing the parameters to the constructor? Since the GraphicObject can be any of the classes that extend it, I need to know somehow which class it is and here I have to use the class that extends it, so I'm trying reflection, but so far only null exception on this.I have a quick question. How do I create a new