Re: the new for loop for Collections does not perform the same as the Iterator for Tomcat-sessions

From:
Lew <lew@lewscanon.com>
Newsgroups:
comp.lang.java.programmer
Date:
Wed, 05 Sep 2007 09:26:55 -0400
Message-ID:
<4oadnQNU4JoCM0PbnZ2dnUVZ_tninZ2d@comcast.com>
phi wrote:

Hello

We tried the following code using JDK1.6 and tomcat 5.5 (and tomcat 6.0
as well) to enter a "note"-Object into a session.
The list-Variable is an ArrayList and therefore a Java Collection.

The new for-Loop does NOT do the job: the object "note" is always null
in the sesson.

    for(Note note : list){
        if(note.getNoteId() == noteId.intValue()){
            session.setAttribute("note ", note);
            break;
        }
    }

We converted to the old java style loop (using the iterator) and see:
it works!

    Iterator iter = list.iterator();
    while(iter.hasNext()){
        Note n = (Note) iter.next();
        if(n.getNoteId() == noteId.intValue()){
            session.setAttribute("note", n);
            break;
        }
    }

Any idea what is the differnce between the for(T t: c)-loop and the
Iterator-methods?


None.

The difference must be in the part of the code that you do not show us. Since
the syntax you say works has only raw types in it, I suspect your trouble
relates to generics abuse.

It is best to provide complete examples that illustrate your problem. (Google
for "SSCCE".)

--
Lew

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