setcontent和setcontentobject用的是同一片内存

setcontent 和 setcontentobject用的是同一片内存,也就是在同一个信息里只宜用一个方法,如果用了两个,第二个会重写第一个的内容,收到的会是一个乱码.
Ok I understand now. I didn t remarked that setContent and
setContentObject referred to the same slot.
Thanks a lot,

Emmanuel

Emilio Yamane a écrit :

> My comments after the ">>>":
>
> On 4/21/06, *blanchae at iro.umontreal.ca
> <mailto:blanchae at iro.umontreal.ca>* <blanchae at iro.umontreal.ca
> <mailto:blanchae at iro.umontreal.ca>> wrote:
>
>     A test I just did:
>
>     sendMessageAndObject(ACLMessage.AGREE,"MAP_DATA",new
>     String("ABCDEFGH"), msg.getSender());
>
>     and here is the message that is shown on my console (Corresponding
>     to the
>     following call inside my sendMessageAndObject method :
>     System.out.println(msg.getContent()+"  "+msg.getContentObject()); )
>
>     ¼? ?ABCDEFGH  ABCDEFGH
>
>     Sounds very very strange to me...
>     why "MAP_DATA" is not return by getContent?
>
> 
> >>> Because in your method, you call setContent AND setContentObject.
> According to the model, they both would write to the same slot in ACL
> Message (:content).
> 
> >>> After you set the content with "MAP_DATA", you call
> setContentObject and it "rewrites" the content with your String .
> 
>
>     Where do the symbols come from?
>
> 
> >>> Since you called setContentObject after setContent, your message
> carries a serialized java object (in a byte array). When you call
> getContent, it will try to build a String based on the byte array. As
> the byte array contains also information about the String class (and
> not just the String itself), the strange chars are explained.
>
>     Could it be a jade bug?
>
> 
> >>> I took a look at the source code, and it seems OK.
>
>     Emmanuel
>
> 
> >>> []s Emilio
>
> 

评论

1 楼 houruiming 2011-08-26  

tks for your info which helps me a lot.