关于Wrapper Class

public class RunTest{
	public static void main(String[] args) {
		Integer ten=new Integer(10);
		Long nine=new Long(9);
		System.out.println(ten+nine);
		int i=1;
		System.out.println(i+ten);
	}
}

大家觉得这道题会输出什么？会不会Error？

刚开始我看到的答案是：Error，解释如下：

The wrapper classes cannot be used like primitives.



Wrapper classes have similar names to primitives but all start with upper case letters.Thus in this case we have int as a primitive and Integer as a wrapper.

The objective do not specifically mention the wrapper classes but don't be surprised if they come up .



但是当我真正在试验之后发现竟然可以输出：19、11；

想了想，可能此题是jdk1.4时候的吧，自从v5之后自动拆装箱，就可以输出结果了，应该是这样的。




大家也讨论下。