The content objects created are instances of the classes produced by the binding compiler.

Apart from a binding compiler, a JAXB

implementation must provide runtime APIs for JAXB-related operations such as marshalling. The APIs are provided as a part of the binding framework. The binding framework comprises of a main package, javax.xml.bind. This package contains classes and interfaces for performing operations such as unmarshalling, marshalling, and validation (marshalling and validation will be covered later).

Validating the Source Data: You can validate source data against an associated schema as part of the unmarshalling operation. JAXB providers have a lot of flexibility here. The JAXB specification mandates that all provider implementations report validation errors when the errors are encountered, but the implementation does not have to stop processing the data. It is possible for a JAXB implementation to successfully unmarshal an invalid XML document, and build a Java content tree. However, the result won’t be valid.

The main requirement is that all JAXB implementations must be able to unmarshal valid documents. Additionally, you also have the flexibility of turning the validations witch off if you don’t want to incur the additional validation processing overhead.

III. Marshal the Content Tree:

Marshalling is the opposite of unmarshalling. Marshalling involves transforming the content tree into a XML document.

Features of JAXB 2.0

JAXB is one of the APIs included with the Java EE platform and also a part of Java Web Services Development Pack (JWSDP). In this

article we are discussing the features of JAXB 2.0; However JAXB 2.1 is available for downloading.

JAXB 2.0 includes some new features:

• It supports for all of the XML Schema constructs.

• It includes parameterized types also.

• It allows us to bind Java-to-XML by using the annotations.

• In this version setValidation () method of the UnMarshaller interface has been replaced with the JAXP 1.3 validation.

• The new version of JAXB (JAXB 2.0) requires smaller runtime libraries that require lesser runtime memory.

• JAXB 2.0 generates a value class instead of an interface and its implementation class. For each toplevel element, JAXB 2.0 generates a Factory class method instead of an interface and an implementation class.

• It generates significantly fewer Java classes from a schema.

How JAXB 2.0 works

To understand how to process XML documents in Java with JAXB 2.0, one need to give a closer look at the two main JAXB components:

I The binding compiler (which binds a