Java語句塊執行順序

運行以下程序：

HelloA.java

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

HelloB.java

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();
	}

}

輸出結果：

static A
static B
I'm A class
HelloA
I'm B class
HelloB

-think why ？