JAXB Version, Namespace, and Schema Attributes

All JAXB binding declarations files must begin with:

• JAXB version number

• Namespace declarations

• Schema name and node

The version, namespace, and schema declarations in bindings.xjb are as follows:

<jxb:bindings version="1.0"
              xmlns:jxb="http://java.sun.com/xml/ns/jaxb"
              xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <jxb:bindings schemaLocation="po.xsd" node="/xs:schema">
        ...
        binding-declarations        ...
  </jxb:bindings>
<!-- schemaLocation="po.xsd" node="/xs:schema" -->
</jxb:bindings>

JAXB Version Number

An XML file with a root element of <jaxb:bindings> is considered an external binding file. The root element must specify the JAXB version attribute with which its binding declarations must comply; specifically the root <jxb:bindings> element must contain either a <jxb:version> declaration or a version attribute. By contrast, when making binding declarations inline, the JAXB version number is made as attribute of the <xsd:schema> declaration:

<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
            xmlns:jxb="http://java.sun.com/xml/ns/jaxb"
            jxb:version="1.0">

Namespace Declarations

As shown in JAXB Version, Namespace, and Schema Attributes, the namespace declarations in the external binding declarations file include both the JAXB namespace and the XMLSchema namespace. Note that the prefixes used in this example could in fact be anything you want; the important thing is to consistently use whatever prefixes you define here in subsequent declarations in the file.

Schema Name and Schema Node

The fourth line of the code in JAXB Version, Namespace, and Schema Attributes specifies the name of the schema to which this binding declarations file will apply, and the schema node at which the customizations will first take effect. Subsequent binding declarations in this file will reference specific nodes within the schema, but this first declaration should encompass the schema as a whole; for example, in bindings.xjb:

<jxb:bindings schemaLocation="po.xsd" node="/xs:schema">