navigator.java

XML的解析、编译、查询等技术的JAVA源代码。

     *
     *  @see #isDocument
     *  @see #isElement
     *
     *  @param contextNode the context node
     *
     *  @return the parent of the context node, or null if this is a document node.
     *
     *  @throws UnsupportedAxisException if the parent axis is not
     *          supported by the model
     */
    Object getParentNode(Object contextNode)
        throws UnsupportedAxisException;
    
    /** Retrieve the namespace URI of the given element node.
     *
     *  @param element the context element node
     *
     *  @return the namespace URI of the element node
     */
    String getElementNamespaceUri(Object element);    

    /** Retrieve the local name of the given element node.
     *
     *  @param element the context element node
     *
     *  @return the local name of the element node
     */
    String getElementName(Object element);    

    /** Retrieve the qualified name of the given element node.
     *
     *  @param element the context element node
     *
     *  @return the qualified name of the element node
     */
    String getElementQName(Object element);

    /** Retrieve the namespace URI of the given attribute node.
     *
     *  @param attr the context attribute node
     *
     *  @return the namespace URI of the attribute node
     */
    String getAttributeNamespaceUri(Object attr);    

    /** Retrieve the local name of the given attribute node.
     *
     *  @param attr the context attribute node
     *
     *  @return the local name of the attribute node
     */
    String getAttributeName(Object attr);

    /** Retrieve the qualified name of the given attribute node.
     *
     *  @param attr the context attribute node
     *
     *  @return the qualified name of the attribute node
     */
    String getAttributeQName(Object attr);

    /** Retrieve the target of a processing-instruction.
     *
     *  @param pi the context processing-instruction node
     *
     *  @return the target of the processing-instruction node
     */
    String getProcessingInstructionTarget(Object pi);

    /** Retrieve the data of a processing-instruction.
     *
     *  @param pi the context processing-instruction node
     *
     *  @return the data of the processing-instruction node
     */
    String getProcessingInstructionData(Object pi);

    // ----------------------------------------------------------------------
    //     isXXX testers
    // ----------------------------------------------------------------------

    /** Returns whether the given object is a document node. A document node
     *  is the node that is selected by the XPath expression <code>/</code>.
     *
     *  @param object the object to test
     *
     *  @return <code>true</code> if the object is a document node,
     *          else <code>false</code>
     */
    boolean isDocument(Object object);

    /** Returns whether the given object is an element node.
     *
     *  @param object the object to test
     *
     *  @return <code>true</code> if the object is an element node,
     *          else <code>false</code>
     */
    boolean isElement(Object object);

    /** Returns whether the given object is an attribute node. 
     *
     *  @param object the object to test
     *
     *  @return <code>true</code> if the object is an attribute node,
     *          else <code>false</code>
     */
    boolean isAttribute(Object object);

    /** Returns whether the given object is a namespace node. 
     *
     *  @param object the object to test
     *
     *  @return <code>true</code> if the object is a namespace node,
     *          else <code>false</code>
     */
    boolean isNamespace(Object object);

    /** Returns whether the given object is a comment node. 
     *
     *  @param object the object to test
     *
     *  @return <code>true</code> if the object is a comment node,
     *          else <code>false</code>
     */
    boolean isComment(Object object);

    /** Returns whether the given object is a text node. 
     *
     *  @param object the object to test
     *
     *  @return <code>true</code> if the object is a text node,
     *          else <code>false</code>
     */
    boolean isText(Object object);

    /** Returns whether the given object is a processing-instruction node.
     *
     *  @param object the object to test
     *
     *  @return <code>true</code> if the object is a processing-instruction node,
     *          else <code>false</code>
     */
    boolean isProcessingInstruction(Object object);

    // ----------------------------------------------------------------------
    //     String-Value extractors
    // ----------------------------------------------------------------------

    /** Retrieve the string-value of a comment node.
     * This may be the empty string if the comment is empty,
     * but must not be null.
     *
     *  @param comment the comment node
     *
     *  @return the string-value of the node
     */
    String getCommentStringValue(Object comment);

    /** Retrieve the string-value of an element node.
     * This may be the empty string if the element is empty,
     * but must not be null.
     *
     *  @param element the comment node.
     *
     *  @return the string-value of the node.
     */
    String getElementStringValue(Object element);

    /** Retrieve the string-value of an attribute node. 
     *  This should be the XML 1.0 normalized attribute value.
     *  This may be the empty string but must not be null. 
     *
     *  @param attr the attribute node
     *
     *  @return the string-value of the node
     */
    String getAttributeStringValue(Object attr);

    /** Retrieve the string-value of a namespace node.
     * This is generally the namespace URI.
     * This may be the empty string but must not be null.
     *
     *  @param ns the namespace node
     *
     *  @return the string-value of the node
     */
    String getNamespaceStringValue(Object ns);

    /** Retrieve the string-value of a text node.
     * This must not be null and should not be the empty string.
     * The XPath data model does not allow empty text nodes.
     *
     *  @param text the text node
     *
     *  @return the string-value of the node
     */
    String getTextStringValue(Object text);

    // ----------------------------------------------------------------------
    //     General utilities
    // ----------------------------------------------------------------------

    /** Retrieve the namespace prefix of a namespace node.
     *
     *  @param ns the namespace node
     *
     *  @return the prefix associated with the node
     */
    String getNamespacePrefix(Object ns);

    
    /** Translate a namespace prefix to a namespace URI, <strong>possibly</strong>
     *  considering a particular element node.
     *
     *  <p>
     *  Strictly speaking, prefix-to-URI translation should occur
     *  irrespective of any element in the document.  This method
     *  is provided to allow a non-conforming ease-of-use enhancement.
     *  </p>
     *
     *  @see NamespaceContext
     *
     *  @param prefix the prefix to translate
     *  @param element the element to consider during translation
     *
     *  @return the namespace URI associated with the prefix
     */
    String translateNamespacePrefixToUri(String prefix,
                                         Object element);

    /** Returns a parsed form of the given XPath string, which will be suitable
     *  for queries on documents that use the same navigator as this one.
     *
     *  @see XPath
     *
     *  @param xpath the XPath expression
     *
     *  @return a new XPath expression object
     *
     *  @throws SAXPathException if the string is not a syntactically 
     *      correct XPath expression
     */
    XPath parseXPath(String xpath) throws SAXPathException;

    /**
     *  Returns the element whose ID is given by elementId.
     *  If no such element exists, returns null.
     *  Attributes with the name "ID" are not of type ID unless so defined.
     *  Implementations that do not know whether attributes are of type ID or
     *  not are expected to return null.
     *
     *  @param contextNode   a node from the document in which to look for the
     *                       id
     *  @param elementId   id to look for
     *
     *  @return   element whose ID is given by elementId, or null if no such
     *            element exists in the document or if the implementation
     *            does not know about attribute types
     */
    Object getElementById(Object contextNode,
                          String elementId);

    /** Returns a number that identifies the type of node that the given
     *  object represents in this navigator.
     * 
     * @param node ????
     * @return ????
     *
     *  @see org.jaxen.pattern.Pattern
     */
    short getNodeType(Object node);
}