Class NamespaceMapper


public final class NamespaceMapper extends NamespacePrefixMapper
  • Constructor Details

  • Method Details

    • getPreferredPrefix

      public String getPreferredPrefix(String namespaceUri, String suggestion, boolean requirePrefix)
      Description copied from class: NamespacePrefixMapper
      Returns a preferred prefix for the given namespace URI. This method is intended to be overrided by a derived class.

      As noted in the return value portion of the javadoc, there are several cases where the preference cannot be honored. Specifically, as of JAXB RI 2.0 and onward:

      1. If the prefix returned is already in use as one of the in-scope namespace bindings. This is partly necessary for correctness (so that we don't unexpectedly change the meaning of QNames bound to String), partly to simplify the marshaller.
      2. If the prefix returned is "" yet the current JAXBContext includes classes that use the empty namespace URI. This allows the JAXB RI to reserve the "" prefix for the empty namespace URI, which is the only possible prefix for the URI. This restriction is also to simplify the marshaller.
      Specified by:
      getPreferredPrefix in class NamespacePrefixMapper
      Parameters:
      namespaceUri - The namespace URI for which the prefix needs to be found. Never be null. "" is used to denote the default namespace.
      suggestion - When the content tree has a suggestion for the prefix to the given namespaceUri, that suggestion is passed as a parameter. Typicall this value comes from the QName.getPrefix to show the preference of the content tree. This parameter may be null, and this parameter may represent an already occupied prefix.
      requirePrefix - If this method is expected to return non-empty prefix. When this flag is true, it means that the given namespace URI cannot be set as the default namespace.
      Returns:
      null if there's no prefered prefix for the namespace URI. In this case, the system will generate a prefix for you. Otherwise the system will try to use the returned prefix, but generally there's no guarantee if the prefix will be actually used or not. return "" to map this namespace URI to the default namespace. Again, there's no guarantee that this preference will be honored. If this method returns "" when requirePrefix=true, the return value will be ignored and the system will generate one.
    • setContextualNamespace

      public void setContextualNamespace(String[] contextualNamespaceDecls)
    • getContextualNamespaceDecls

      public String[] getContextualNamespaceDecls()
      Description copied from class: NamespacePrefixMapper
      Returns a list of (prefix,namespace URI) pairs that represents namespace bindings available on ancestor elements (that need not be repeated by the JAXB RI.)

      Sometimes JAXB is used to marshal an XML document, which will be used as a subtree of a bigger document. When this happens, it's nice for a JAXB marshaller to be able to use in-scope namespace bindings of the larger document and avoid declaring redundant namespace URIs.

      This is automatically done when you are marshalling to XMLStreamWriter, XMLEventWriter, DOMResult, or Node, because those output format allows us to inspect what's currently available as in-scope namespace binding. However, with other output format, such as OutputStream, the JAXB RI cannot do this automatically. That's when this method comes into play.

      Namespace bindings returned by this method will be used by the JAXB RI, but will not be re-declared. They are assumed to be available when you insert this subtree into a bigger document.

      It is NOT OK to return the same binding, or give the receiver a conflicting binding information. It's a responsibility of the caller to make sure that this doesn't happen even if the ancestor elements look like:

      
         <foo:abc xmlns:foo="abc">
           <foo:abc xmlns:foo="def">
             <foo:abc xmlns:foo="abc">
               ... JAXB marshalling into here.
             </foo:abc>
           </foo:abc>
         </foo:abc>
       
      Overrides:
      getContextualNamespaceDecls in class NamespacePrefixMapper
      Returns:
      always return a non-null (but possibly empty) array. The array stores data like (prefix1,nsUri1,prefix2,nsUri2,...) Use an empty string to represent the empty namespace URI and the default prefix. Null is not allowed as a value in the array.