Compare two XML files: Analysis and Design

Question

Hi, Java/XML/JDOM experts,
I realised that an open source of Java utility to compare two XML is still missing. So I would like to write one for my JDOM excises.
I plan to do it in three steps:
1.Define the problem domain.
2.Design the classes to be developed.
3.Coding
Below is the problem domain. Would you review it and tell me if it is fine?
Best regards,
AG
Compare two XML files
Schema assumption:
The xml files used for the comparison must have the same schema.
Definition:
1. Two elements of simple type are said equal if their name and value are identical.
2. Two elements of complex type are said comparable if their name, attributes are identical.
3. Two elements of complex type are said equal if they are comparable and their children elements are identical.

Answer 1

Hi,
Thanks for reviewing my idea.
The xml files used for the comparison must have the
same schema.Including not having a schema at all? And if they do
have a schema, must they be valid according to the
schema?I will only support schema based xml files. To include a schema is a good practice. So I will valid them agaisnt schema (is this possible with JDOM? I am testing ...)
>
2. Two elements of complex type are said comparableif
their name, attributes are identical.
3. Two elements of complex type are said equal ifthey
are comparable and their children elements are
identical.Do you plan to require child elements to appear in the
same order for the two documents to be equal? (Note
that XML specifically says that the order of
attributes is not significant.)No. The order is not significant as I use the attributes as the keys to find comparable element counterpart.
Here is the sample code already tested. Any comments are welcome!
The next step is to define the "delta xml schema" that will guide me to store the comparasion results. Do you have any suggestions?
Regards.
AG
public static boolean comparable(Element element1, Element element2)
     boolean returnValue=false;
     if (element1.getName()!=element2.getName()) {
          return returnValue;
} else {
          returnValue=true;
                    System.out.println ("place 2");
     List attributeList=element1.getAttributes();
     Iterator attributeIterator=attributeList.iterator();
     Attribute workingAttribute=null;
     while (attributeIterator.hasNext()) {
                         if (!workingAttribute.getValue().equals(
                         element2.getAttribute(workingAttribute.getName(), workingAttribute.getNamespace()).getValue()))
                              returnValue=false;
                              break;
     return returnValue;