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implementation of the schema derived classes, and they may also expose

the methods from the schema derived classes as part of the domain specific

class. Additionally, as a side effect, if the developer is not careful, this may

result in tightly binding the business logic to the schemas from which the

classes were generated.

c. The developer can use aggregation or composition and design domain 

specific classes that only expose domain oriented methods and delegate to

the schema derived classes. Since the domain specific classes only depend

on the interfaces of the schema derived classes, the interfaces of the

domain specific classes may therefore not be as sensitive to changes in the

original schema.

Note that when no well defined schema or variable in nature (abstract) or in

number (including new schema revisions) is available, JAXB may be cumber 

some to use due to the tight coupling between the schemas and the schema 

derived classes. Also note that the more abstract the schema, the less effective the

binding.

Consider using the XML data binding programming model, such as JAXB,

when you have any of the following conditions:

E

You want to deal directly with plain Java objects and do not care about, nor 

want to handle, document representation.

E

You are consuming or producing documents.

E

You do not need to maintain some aspects of a document, such as comments 

and entity references. The JAXB specification does not require giving access 

to the underlying document representation (infoset). For example, the JAXB 

reference implementation is based on SAX 2.0 and therefore does not maintain 

an underlying document representation. However, other implementations may 

be layered on top of a DOM representation. A developer may fall back on this 

DOM representation to access unexposed infoset elements.

E

You want to process the content tree more than once.

E

You want random access to parts of the document. For example, you may want 

to traverse back and forth within the document.

E

Memory usage may be less of an issue. A JAXB implementation, such as the 

standard implementation, creates a Java representation of the content of a doc 

ument that is much more compact than the equivalent DOM tree. The standard