java构造器如何创建实例？

public class Main {

    public Main() {

    }

    public static void main(String[] args) throws IllegalAccessException, InvocationTargetException, InstantiationException {

        Class c = Main.class;

        Constructor[] ctors = c.getConstructors();

        Constructor ctor = null;

        for (int i = 0; i < ctors.length; i++) {

            ctor = ctors[i];

            if (ctor.getGenericParameterTypes().length == 0)     // 需要找到默认构造函数创建实例

                break;

        }

        System.out.println(ctor.newInstance().getClass().getCanonicalName());

    }

}