org.dom4j.Node Maven / Gradle / Ivy
/*
* Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
*
* This software is open source.
* See the bottom of this file for the licence.
*/
package org.dom4j;
import java.io.IOException;
import java.io.Writer;
import java.util.List;
/**
* Node defines the polymorphic behavior for all XML nodes in a
* dom4j tree.
*
* A node can be output as its XML format, can be detached from its position in
* a document and can have XPath expressions evaluated on itself.
*
* A node may optionally support the parent relationship and may be read only.
*
* @author James Strachan
* @version $Revision: 1.31 $
*
* @see #supportsParent
* @see #isReadOnly
*/
public interface Node extends Cloneable {
// W3C DOM complient node type codes
/** Matches Element nodes */
short ANY_NODE = 0;
/** Matches Element nodes */
short ELEMENT_NODE = 1;
/** Matches elements nodes */
short ATTRIBUTE_NODE = 2;
/** Matches elements nodes */
short TEXT_NODE = 3;
/** Matches elements nodes */
short CDATA_SECTION_NODE = 4;
/** Matches elements nodes */
short ENTITY_REFERENCE_NODE = 5;
/** Matches elements nodes */
// public static final short ENTITY_NODE = 6;
/** Matches ProcessingInstruction */
short PROCESSING_INSTRUCTION_NODE = 7;
/** Matches Comments nodes */
short COMMENT_NODE = 8;
/** Matches Document nodes */
short DOCUMENT_NODE = 9;
/** Matches DocumentType nodes */
short DOCUMENT_TYPE_NODE = 10;
// public static final short DOCUMENT_FRAGMENT_NODE = 11;
// public static final short NOTATION_NODE = 12;
/** Matchs a Namespace Node - NOTE this differs from DOM */
// XXXX: ????
short NAMESPACE_NODE = 13;
/** Does not match any valid node */
short UNKNOWN_NODE = 14;
/** The maximum number of node types for sizing purposes */
short MAX_NODE_TYPE = 14;
/**
*
* supportsParent returns true if this node supports the
* parent relationship.
*
*
*
* Some XML tree implementations are singly linked and only support downward
* navigation through children relationships. The default case is that both
* parent and children relationships are supported though for memory and
* performance reasons the parent relationship may not be supported.
*
*
* @return true if this node supports the parent relationship or false it is
* not supported
*/
boolean supportsParent();
/**
*
* getParent returns the parent Element if
* this node supports the parent relationship or null if it is the root
* element or does not support the parent relationship.
*
*
*
* This method is an optional feature and may not be supported for all
* Node implementations.
*
*
* @return the parent of this node or null if it is the root of the tree or
* the parent relationship is not supported.
*/
Element getParent();
/**
*
* setParent sets the parent relationship of this node if the
* parent relationship is supported or does nothing if the parent
* relationship is not supported.
*
*
*
* This method should only be called from inside an Element
* implementation method and is not intended for general use.
*
*
* @param parent
* is the new parent of this node.
*/
void setParent(Element parent);
/**
*
* getDocument returns the Document that this
* Node is part of if this node supports the parent
* relationship.
*
*
*
* This method is an optional feature and may not be supported for all
* Node implementations.
*
*
* @return the document of this node or null if this feature is not
* supported or the node is not associated with a
* Document
*/
Document getDocument();
/**
*
* setDocument sets the document of this node if the parent
* relationship is supported or does nothing if the parent relationship is
* not supported.
*
*
*
* This method should only be called from inside a Document
* implementation method and is not intended for general use.
*
*
* @param document
* is the new document of this node.
*/
void setDocument(Document document);
/**
*
* isReadOnly returns true if this node is read only and
* cannot be modified. Any attempt to modify a read-only Node
* will result in an UnsupportedOperationException being
* thrown.
*
*
* @return true if this Node is read only and cannot be
* modified otherwise false.
*/
boolean isReadOnly();
/**
*
* hasContent returns true if this node is a Branch (either
* an Element or a Document) and it contains at least one content node such
* as a child Element or Text node.
*
*
* @return true if this Node is a Branch with a nodeCount()
* of one or more.
*/
boolean hasContent();
/**
*
* getName returns the name of this node. This is the XML
* local name of the element, attribute, entity or processing instruction.
* For CDATA and Text nodes this method will return null.
*
*
* @return the XML name of this node
*/
String getName();
/**
*
* Sets the text data of this node or this method will throw an
* UnsupportedOperationException if it is read-only.
*
*
* @param name
* is the new name of this node
*/
void setName(String name);
/**
*
* Returns the text of this node.
*
*
* @return the text for this node.
*/
String getText();
/**
*
* Sets the text data of this node or this method will throw an
* UnsupportedOperationException if it is read-only.
*
*
* @param text
* is the new textual value of this node
*/
void setText(String text);
/**
* Returns the XPath string-value of this node. The behaviour of this method
* is defined in the XPath
* specification .
*
* @return the text from all the child Text and Element nodes appended
* together.
*/
String getStringValue();
/**
*
* Returns the XPath expression which will return a node set containing the
* given node such as /a/b/@c. No indexing will be used to restrict the
* path if multiple elements with the same name occur on the path.
*
*
* @return the XPath expression which will return a nodeset containing at
* least this node.
*/
String getPath();
/**
* Returns the relative XPath expression which will return a node set
* containing the given node such as a/b/@c. No indexing will be used to
* restrict the path if multiple elements with the same name occur on the
* path.
*
* @param context
* is the parent context from which the relative path should
* start. If the context is null or the context is not an
* ancestor of this node then the path will be absolute and start
* from the document and so begin with the '/' character.
*
* @return the XPath expression relative to the given context which will
* return a nodeset containing at least this node.
*/
String getPath(Element context);
/**
*
* Returns the XPath expression which will return a nodeset of one node
* which is the current node. This method will use the XPath index operator
* to restrict the path if multiple elements with the same name occur on the
* path.
*
*
* @return the XPath expression which will return a nodeset containing just
* this node.
*/
String getUniquePath();
/**
*
* Returns the relative unique XPath expression from the given context which
* will return a nodeset of one node which is the current node. This method
* will use the XPath index operator to restrict the path if multiple
* elements with the same name occur on the path.
*
*
* @param context
* is the parent context from which the path should start. If the
* context is null or the context is not an ancestor of this node
* then the path will start from the document and so begin with
* the '/' character.
*
* @return the XPath expression relative to the given context which will
* return a nodeset containing just this node.
*/
String getUniquePath(Element context);
/**
*
* asXML returns the textual XML representation of this node.
*
*
* @return the XML representation of this node
*/
String asXML();
/**
*
* write writes this node as the default XML notation for
* this node. If you wish to control the XML output (such as for pretty
* printing, changing the indentation policy etc.) then please use {@link
* org.dom4j.io.XMLWriter} or its derivations.
*
*
* @param writer
* is the Writer to output the XML to
*
* @throws IOException
* DOCUMENT ME!
*/
void write(Writer writer) throws IOException;
/**
* Returns the code according to the type of node. This makes processing
* nodes polymorphically much easier as the switch statement can be used
* instead of multiple if (instanceof) statements.
*
* @return a W3C DOM complient code for the node type such as ELEMENT_NODE
* or ATTRIBUTE_NODE
*/
short getNodeType();
/**
* DOCUMENT ME!
*
* @return the name of the type of node such as "Document", "Element",
* "Attribute" or "Text"
*/
String getNodeTypeName();
/**
*
* Removes this node from its parent if there is one. If this node is the
* root element of a document then it is removed from the document as well.
*
*
*
* This method is useful if you want to remove a node from its source
* document and add it to another document. For example
*
* Node node = ...; Element someOtherElement = ...;
* someOtherElement.add( node.detach() );
*
* @return the node that has been removed from its parent node if any and
* its document if any.
*/
Node detach();
/**
*
* selectNodes evaluates an XPath expression and returns the
* result as a List of Node instances or
* String instances depending on the XPath expression.
*
*
* @param xpathExpression
* is the XPath expression to be evaluated
*
* @return the list of Node or String
* instances depending on the XPath expression
*/
List selectNodes(String xpathExpression);
/**
*
* selectObject evaluates an XPath expression and returns the
* result as an {@link Object}. The object returned can either be a {@link
* List} of one or more {@link Node}instances or a scalar object like a
* {@link String}or a {@link Number}instance depending on the XPath
* expression.
*
*
* @param xpathExpression
* is the XPath expression to be evaluated
*
* @return the value of the XPath expression as a {@link List}of {@link
* Node} instances, a {@link String}or a {@link Number}instance
* depending on the XPath expression.
*/
Object selectObject(String xpathExpression);
/**
*
* selectNodes evaluates an XPath expression then sorts the
* results using a secondary XPath expression Returns a sorted
* List of Node instances.
*
*
* @param xpathExpression
* is the XPath expression to be evaluated
* @param comparisonXPathExpression
* is the XPath expression used to compare the results by for
* sorting
*
* @return the list of Node instances sorted by the
* comparisonXPathExpression
*/
List selectNodes(String xpathExpression, String comparisonXPathExpression);
/**
*
* selectNodes evaluates an XPath expression then sorts the
* results using a secondary XPath expression Returns a sorted
* List of Node instances.
*
*
* @param xpathExpression
* is the XPath expression to be evaluated
* @param comparisonXPathExpression
* is the XPath expression used to compare the results by for
* sorting
* @param removeDuplicates
* if this parameter is true then duplicate values (using the
* comparisonXPathExpression) are removed from the result List.
*
* @return the list of Node instances sorted by the
* comparisonXPathExpression
*/
List selectNodes(String xpathExpression, String comparisonXPathExpression,
boolean removeDuplicates);
/**
*
* selectSingleNode evaluates an XPath expression and returns
* the result as a single Node instance.
*
*
* @param xpathExpression
* is the XPath expression to be evaluated
*
* @return the Node matching the XPath expression
*/
Node selectSingleNode(String xpathExpression);
/**
*
* valueOf evaluates an XPath expression and returns the
* textual representation of the results the XPath string-value of this
* node. The string-value for a given node type is defined in the XPath specification .
*
*
* @param xpathExpression
* is the XPath expression to be evaluated
*
* @return the string-value representation of the results of the XPath
* expression
*/
String valueOf(String xpathExpression);
/**
*
* numberValueOf evaluates an XPath expression and returns
* the numeric value of the XPath expression if the XPath expression results
* in a number, or null if the result is not a number.
*
*
* @param xpathExpression
* is the XPath expression to be evaluated
*
* @return the numeric result of the XPath expression or null if the result
* is not a number.
*/
Number numberValueOf(String xpathExpression);
/**
*
* matches returns true if evaluating the given XPath
* expression on this node returns a non-empty node set containing this
* node.
*
*
*
* This method does not behave like the <xsl:if> element - if you want
* that behaviour, to evaluate if an XPath expression matches something,
* then you can use the following code to be equivalent...
*
* if ( node.selectSingleNode( "/some/path" ) != nulll )
*
* @param xpathExpression
* is an XPath expression
*
* @return true if this node is returned by the given XPath expression
*/
boolean matches(String xpathExpression);
/**
*
* createXPath creates an XPath object for the given
* xpathExpression. The XPath object allows the variable context to be
* specified.
*
*
* @param xpathExpression
* is the XPath expression to be evaluated
*
* @return an XPath object represeting the given expression
*
* @throws InvalidXPathException
* if the XPath expression is invalid
*/
XPath createXPath(String xpathExpression) throws InvalidXPathException;
/**
*
* asXPathResult returns a version of this node which is
* capable of being an XPath result. The result of an XPath expression
* should always support the parent relationship, whether the original XML
* tree was singly or doubly linked. If the node does not support the parent
* relationship then a new node will be created which is linked to its
* parent and returned.
*
*
* @param parent
* DOCUMENT ME!
*
* @return a Node which supports the parent relationship
*/
Node asXPathResult(Element parent);
/**
*
* accept is the method used in the Visitor Pattern.
*
*
* @param visitor
* is the visitor in the Visitor Pattern
*/
void accept(Visitor visitor);
/**
*
* clone will return a deep clone or if this node is
* read-only then clone will return the same instance.
*
*
* @return a deep clone of myself or myself if I am read only.
*/
Object clone();
}
/*
* Redistribution and use of this software and associated documentation
* ("Software"), with or without modification, are permitted provided that the
* following conditions are met:
*
* 1. Redistributions of source code must retain copyright statements and
* notices. Redistributions must also contain a copy of this document.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. The name "DOM4J" must not be used to endorse or promote products derived
* from this Software without prior written permission of MetaStuff, Ltd. For
* written permission, please contact [email protected].
*
* 4. Products derived from this Software may not be called "DOM4J" nor may
* "DOM4J" appear in their names without prior written permission of MetaStuff,
* Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
*
* 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
*
* THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
*/