java的Constructor和static块

public class demo988{public static void main(String args[]){A a = new B();System.out.println();a = new B();}}class A{static{System.out.print(1);}public A(){System.out.print(2);}}class B extends A{static{System.out.print("a");}public B(){System.out.print("b");}}

优先执行static块且只执行一次！

运行结果：

1a2b
2b