Red Hat Training

A Red Hat training course is available for Red Hat Fuse

30.2. XML Namespace Mapping


XML Schema type, group, and element definitions are scoped using namespaces. The namespaces prevent possible naming clashes between entities that use the same name. Java packages serve a similar purpose. Therefore, Apache CXF maps the target namespace of a schema document into a package containing the classes necessary to implement the structures defined in the schema document.

Package naming

The name of the generated package is derived from a schema's target namespace using the following algorithm:
  1. The URI scheme, if present, is stripped.
    Apache CXF will only strip the http:, https:, and urn: schemes.
    For example, the namespace http:\\\types\widgetTypes.xsd becomes \\\types\widgetTypes.xsd.
  2. The trailing file type identifier, if present, is stripped.
    For example, \\\types\widgetTypes.xsd becomes \\\types\widgetTypes.
  3. The resulting string is broken into a list of strings using / and : as separators.
    So, \\\types\widgetTypes becomes the list {"", "types", "widgetTypes"}.
  4. If the first string in the list is an internet domain name, it is decomposed as follows:
    1. The leading www. is stripped.
    2. The remaining string is split into its component parts using the . as the separator.
    3. The order of the list is reversed.
    So, {"", "types", "widgetTypes"} becomes {"com", "widegetvendor", "types", "widgetTypes"}
    Internet domain names end in one of the following: .com, .net, .edu, .org, .gov, or in one of the two-letter country codes.
  5. The strings are converted into all lower case.
    So, {"com", "widegetvendor", "types", "widgetTypes"} becomes {"com", "widegetvendor", "types", "widgettypes"}.
  6. The strings are normalized into valid Java package name components as follows:
    1. If the strings contain any special characters, the special characters are converted to an underscore(_).
    2. If any of the strings are a Java keyword, the keyword is prefixed with an underscore(_).
    3. If any of the strings begin with a numeral, the string is prefixed with an underscore(_).
  7. The strings are concatenated using . as a separator.
    So, {"com", "widegetvendor", "types", "widgettypes"} becomes the package name com.widgetvendor.types.widgettypes.
The XML Schema constructs defined in the namespace http:\\\types\widgetTypes.xsd are mapped to the Java package com.widgetvendor.types.widgettypes.

Package contents

A JAXB generated package contains the following:
  • A class implementing each complex type defined in the schema
    For more information on complex type mapping see Chapter 33, Using Complex Types.
  • An enum type for any simple types defined using the enumeration facet
    For more information on how enumerations are mapped see Section 32.3, “Enumerations”.
  • A public ObjectFactory class that contains methods for instantiating objects from the schema
    For more information on the ObjectFactory class see Section 30.3, “The Object Factory”.
  • A file that provides metadata about the classes in the package