Kirsty Beaton

Hello all,

I am creating a simple Web Service. For the time being, I just want to have 3 or 4 Java object instances that will persist, that I can perform queries on. I want to have these instances stored in an XML file which I can read and write to.
Right now my problem is writing the objects to XML.
It seems like the best way to go about doing this is to create a class for each object in Java, then in a driver of some sort create instances of these objects, and write them to XML using JAXB.

I've read some tutorials on JAXB and with the help of Netbeans' generated code for marshalling, I have managed to write one instance to XML. My question is, what is the best way to write a group of instances into one XML file? Do I need to write a class for an object that represents a collection of the objects (for example, I want to store a group of "Book" objects, do I need to write a "BookList" class, and write one instance of "BookList" using JAXB)?

I have also read that for JAXB to work I need to have an XML schema, an "xsd" file. Is this something I write myself?

I am fairly new to XML so any help would be appreciated.
Thank you.

Thank you all for your helpful responses.

Java's starting to come back to me now.

Hi there,
I have been programming in C++ for the last while and am once again using Java. I don't have a lot of experience in Java in the first place so there's a few things that aren't coming back to me right away.

What I am unsure about at the moment is Java's automatic copying of objects.

DocIDFrequencyList is essentially a HashMap.
Is there any difference between the following code snippets?
A:
for ( Map.Entry<String, DocIDFrequencyList> i : other.postingsList.entrySet() ){ postingsList.put( i.getKey(), new DocIDFrequencyList( i.getValue() ) ); }

B:
for ( Map.Entry<String, DocIDFrequencyList> i : other.postingsList.entrySet() ){ postingsList.put( i.getKey(), i.getValue() ); }

Thank you for any help.

Interesting, I had no idea. I will read up on that. Thank you.

I didn't realise it would compile like that (with one "=").

I'll take your word for it.

Campbell Ritchie wrote:

mohamed sanaullah wrote:Change This
if (isFullStack = true){

to this
if (isFullStack == true){ . . .

Surely you mean if (isFullStack) . . . You should never use == true or == false.

Mind if I ask the reasoning behind this? Is it simply a style issue?

All The Pretty Horses by Cormac McCarthy.

I'd avoid the movie though.

In fact, I'd recommend reading anything by Cormac McCarthy.

As someone that is also new to Java, would it be correct to say that lines 2-4 are allocating space for Players? And lines 7-9 are filling that space?

I just started reading the comic book. I've heard the episodes correspond very closely to the book's storyline. I'm waiting to finish reading before I start watching the show, but I'm looking forward to it... the comic has been so addictive. I'd recommend it if you like the show. The illustrations of the zombies are awesome.