Collision Resolution and Global Customizations 
When generating outside-in Web services or Web service proxies, collisions may arise in the mapping between names in the WSDL and the names of the corresponding Java artifacts. For example, a complex type with two elements el_1 and el1 would, by default, be mapped to a Java class with two properties with the same names (el1). As another example, long names in the WSDL document may result in long names of Java classes.
The Web service tools enable you to resolve potential collisions in a number of different ways:
You can use customization options integrated in the wizard for creating outside-in Web services. These customizations are compliant with the JAXB 2.0 specification, Chapter 7.5 <globalBinding> Declaration.
You can use your own external customization files to change the default behavior of the Web services generation tools to change the names of the classes, packages, types and operations in the generated endpoint. Customization files allow you to:
Reuse the types in more than one outside-in Web service
Change the mapping between WSDL namespaces and the packages in the generated classes.
Customization files are files prepared by you in advance. Before using customization files, make sure that they are correct and comply with The Java API for XML-Based Web Services (JAX-WS) 2.0.
More information about the collision resolution options which the framework provides is available in the procedures below.