关于JAVA中继承相关面试extends

如题，面试题如下：

请输入下面代码的运行结果--------extends-----------

class HelloA {public HelloA(){System.out.println("HelloA");}{System.out.println("I'm A class");}static{System.out.println("static A");}}

public class HelloB extends HelloA{public HelloB(){System.out.println("HelloB");}{System.out.println("I'm B class");}static{System.out.println("static B");}public static void main(String[] args) {new HelloB();}}

运行结果如下：

</pre><pre name="code" class="java">static Astatic BI'm A classHelloAI'm B classHelloB