Class NamespaceReducer

  • All Implemented Interfaces:
    javax.xml.transform.Result, Receiver, NamespaceResolver

    public class NamespaceReducer
    extends ProxyReceiver
    implements NamespaceResolver
    NamespaceReducer is a ProxyReceiver responsible for removing duplicate namespace declarations. It also ensures that an xmlns="" undeclaration is output when necessary. Used on its own, the NamespaceReducer simply eliminates unwanted namespace declarations. It can also be subclassed, in which case the subclass can use the services of the NamespaceReducer to resolve QNames.

    The NamespaceReducer also validates namespace-sensitive content.

    • Constructor Detail

      • NamespaceReducer

        public NamespaceReducer()
    • Method Detail

      • startElement

        public void startElement​(int nameCode,
                                 int typeCode,
                                 int locationId,
                                 int properties)
                          throws XPathException
        startElement. This call removes redundant namespace declarations, and possibly adds an xmlns="" undeclaration.
        Specified by:
        startElement in interface Receiver
        Overrides:
        startElement in class ProxyReceiver
        Parameters:
        nameCode - integer code identifying the name of the element within the name pool.
        typeCode - integer code identifying the element's type within the name pool.
        locationId - an integer which can be interpreted using a LocationProvider to return information such as line number and system ID. If no location information is available, the value zero is supplied.
        properties - properties of the element node
        Throws:
        XPathException
      • namespace

        public void namespace​(int namespaceCode,
                              int properties)
                       throws XPathException
        Description copied from class: ProxyReceiver
        Notify a namespace. Namespaces are notified after the startElement event, and before any children for the element. The namespaces that are reported are only required to include those that are different from the parent element; however, duplicates may be reported. A namespace must not conflict with any namespaces already used for element or attribute names.
        Specified by:
        namespace in interface Receiver
        Overrides:
        namespace in class ProxyReceiver
        Parameters:
        namespaceCode - an integer: the top half is a prefix code, the bottom half a URI code. These may be translated into an actual prefix and URI using the name pool. A prefix code of zero represents the empty prefix (that is, the default namespace). A URI code of zero represents a URI of "", that is, a namespace undeclaration.
        properties - The most important property is REJECT_DUPLICATES. If this property is set, the namespace declaration will be rejected if it conflicts with a previous declaration of the same prefix. If the property is not set, the namespace declaration will be ignored if it conflicts with a previous declaration. This reflects the fact that when copying a tree, namespaces for child elements are emitted before the namespaces of their parent element. Unfortunately this conflicts with the XSLT rule for complex content construction, where the recovery action in the event of conflicts is to take the namespace that comes last. XSLT therefore doesn't recover from this error: it sets the REJECT_DUPLICATES flag, and this is treated as a hard error.
        Throws:
        XPathException
      • getURICode

        protected short getURICode​(short prefixCode)
        Get the URI code corresponding to a given prefix code, by searching the in-scope namespaces. This is a service provided to subclasses.
        Parameters:
        prefixCode - the 16-bit prefix code required
        Returns:
        the 16-bit URI code, or -1 if the prefix is not found
      • getURIForPrefix

        public java.lang.String getURIForPrefix​(java.lang.String prefix,
                                                boolean useDefault)
        Get the namespace URI corresponding to a given prefix. Return null if the prefix is not in scope.
        Specified by:
        getURIForPrefix in interface NamespaceResolver
        Parameters:
        prefix - the namespace prefix
        useDefault - true if the default namespace is to be used when the prefix is ""
        Returns:
        the uri for the namespace, or null if the prefix is not in scope
      • iteratePrefixes

        public java.util.Iterator iteratePrefixes()
        Get an iterator over all the prefixes declared in this namespace context. This will include the default namespace (prefix="") and the XML namespace where appropriate
        Specified by:
        iteratePrefixes in interface NamespaceResolver