package net.sf.saxon.tree;
import net.sf.saxon.Configuration;
import net.sf.saxon.om.*;
import net.sf.saxon.pattern.AnyNodeTest;
import net.sf.saxon.pattern.NameTest;
import net.sf.saxon.pattern.NodeTest;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.type.Type;
import net.sf.saxon.value.UntypedAtomicValue;
import net.sf.saxon.value.Value;
import javax.xml.transform.SourceLocator;
/**
* A node in the XML parse tree representing an XML element, character content, or attribute.<P>
* This is the top-level class in the implementation class hierarchy; it essentially contains
* all those methods that can be defined using other primitive methods, without direct access
* to data.
*
* @author Michael H. Kay
*/
public abstract class NodeImpl implements NodeInfo, FingerprintedNode, SourceLocator {
protected ParentNodeImpl parent;
protected int index;
/**
* Chararacteristic letters to identify each type of node, indexed using the node type
* values. These are used as the initial letter of the result of generate-id()
*/
public static final char[] NODE_LETTER =
{'x', 'e', 'a', 't', 'x', 'x', 'x', 'p', 'c', 'r', 'x', 'x', 'x', 'n'};
/**
* Get the value of the item as a CharSequence. This is in some cases more efficient than
* the version of the method that returns a String.
*/
public CharSequence getStringValueCS() {
return getStringValue();
}
/**
* Get the type annotation of this node, if any
*/
public int getTypeAnnotation() {
return StandardNames.XS_UNTYPED;
}
/**
* Get the column number of the node.
* The default implementation returns -1, meaning unknown
*/
public int getColumnNumber() {
return -1;
}
/**
* Get the public identifier of the document entity containing this node.
* The default implementation returns null, meaning unknown
*/
public String getPublicId() {
return null;
}
/**
* Get the document number of the document containing this node. For a free-standing
* orphan node, just return the hashcode.
*/
public int getDocumentNumber() {
return getRoot().getDocumentNumber();
}
/**
* Get the typed value of this node.
* If there is no type annotation, we return the string value, as an instance
* of xs:untypedAtomic
*/
public SequenceIterator getTypedValue() throws XPathException {
return SingletonIterator.makeIterator(new UntypedAtomicValue(getStringValue()));
}
/**
* Get the typed value. The result of this method will always be consistent with the method
* {@link net.sf.saxon.om.Item#getTypedValue()}. However, this method is often more convenient and may be
* more efficient, especially in the common case where the value is expected to be a singleton.
*
* @return the typed value. If requireSingleton is set to true, the result will always be an
* AtomicValue. In other cases it may be a Value representing a sequence whose items are atomic
* values.
* @since 8.5
*/
public Value atomize() throws XPathException {
return new UntypedAtomicValue(getStringValue());
}
/**
* Set the system ID of this node. This method is provided so that a NodeInfo
* implements the javax.xml.transform.Source interface, allowing a node to be
* used directly as the Source of a transformation
*/
public void setSystemId(String uri) {
// overridden in DocumentImpl and ElementImpl
getParent().setSystemId(uri);
}
/**
* Determine whether this is the same node as another node
*
* @return true if this Node object and the supplied Node object represent the
* same node in the tree.
*/
public boolean isSameNodeInfo(NodeInfo other) {
// default implementation: differs for attribute and namespace nodes
return this == other;
}
/**
* The equals() method compares nodes for identity. It is defined to give the same result
* as isSameNodeInfo().
* @param other the node to be compared with this node
* @return true if this NodeInfo object and the supplied NodeInfo object represent
* the same node in the tree.
* @since 8.7 Previously, the effect of the equals() method was not defined. Callers
* should therefore be aware that third party implementations of the NodeInfo interface may
* not implement the correct semantics. It is safer to use isSameNodeInfo() for this reason.
* The equals() method has been defined because it is useful in contexts such as a Java Set or HashMap.
*/
public boolean equals(Object other) {
return other instanceof NodeInfo && isSameNodeInfo((NodeInfo)other);
}
/**
* The hashCode() method obeys the contract for hashCode(): that is, if two objects are equal
* (represent the same node) then they must have the same hashCode()
* @since 8.7 Previously, the effect of the equals() and hashCode() methods was not defined. Callers
* should therefore be aware that third party implementations of the NodeInfo interface may
* not implement the correct semantics.
*/
public int hashCode() {
FastStringBuffer buff = new FastStringBuffer(20);
generateId(buff);
return buff.toString().hashCode();
}
/**
* Get the nameCode of the node. This is used to locate the name in the NamePool
*/
public int getNameCode() {
// default implementation: return -1 for an unnamed node
return -1;
}
/**
* Get the fingerprint of the node. This is used to compare whether two nodes
* have equivalent names. Return -1 for a node with no name.
*/
public int getFingerprint() {
int nameCode = getNameCode();
if (nameCode == -1) {
return -1;
}
return nameCode & 0xfffff;
}
/**
* Get a character string that uniquely identifies this node within this document
* (The calling code will prepend a document identifier)
*/
public void generateId(FastStringBuffer buffer) {
getDocumentRoot().generateId(buffer);
buffer.append(NODE_LETTER[getNodeKind()]);
buffer.append(Long.toString(getSequenceNumber()));
}
/**
* Get the system ID for the node. Default implementation for child nodes.
*/
public String getSystemId() {
return parent.getSystemId();
}
/**
* Get the base URI for the node. Default implementation for child nodes.
*/
public String getBaseURI() {
return parent.getBaseURI();
}
/**
* Get the node sequence number (in document order). Sequence numbers are monotonic but not
* consecutive. In the current implementation, parent nodes (elements and roots) have a zero
* least-significant word, while namespaces, attributes, text nodes, comments, and PIs have
* the top word the same as their owner and the bottom half reflecting their relative position.
* This is the default implementation for child nodes.
* @return the node sequence number
*/
protected long getSequenceNumber() {
NodeImpl prev = this;
for (int i = 0; ; i++) {
if (prev instanceof ParentNodeImpl) {
return prev.getSequenceNumber() + 0x10000 + i;
// note the 0x10000 is to leave room for namespace and attribute nodes.
}
prev = prev.getPreviousInDocument();
}
}
/**
* Determine the relative position of this node and another node, in document order.
* The other node will always be in the same document.
*
* @param other The other node, whose position is to be compared with this node
* @return -1 if this node precedes the other node, +1 if it follows the other
* node, or 0 if they are the same node. (In this case, isSameNode() will always
* return true, and the two nodes will produce the same result for generateId())
*/
public final int compareOrder(NodeInfo other) {
if (other instanceof NamespaceIterator.NamespaceNodeImpl) {
return 0 - other.compareOrder(this);
}
long a = getSequenceNumber();
long b = ((NodeImpl)other).getSequenceNumber();
if (a < b) {
return -1;
}
if (a > b) {
return +1;
}
return 0;
}
/**
* Get the configuration
*/
public Configuration getConfiguration() {
return getDocumentRoot().getConfiguration();
}
/**
* Get the NamePool
*/
public NamePool getNamePool() {
return getDocumentRoot().getNamePool();
}
/**
* Get the prefix part of the name of this node. This is the name before the ":" if any.
*
* @return the prefix part of the name. For an unnamed node, return an empty string.
*/
public String getPrefix() {
int nameCode = getNameCode();
if (nameCode == -1) {
return "";
}
if (NamePool.getPrefixIndex(nameCode) == 0) {
return "";
}
return getNamePool().getPrefix(nameCode);
}
/**
* Get the URI part of the name of this node. This is the URI corresponding to the
* prefix, or the URI of the default namespace if appropriate.
*
* @return The URI of the namespace of this node. For the default namespace, return an
* empty string. For an unnamed node, return the empty string.
*/
public String getURI() {
int nameCode = getNameCode();
if (nameCode == -1) {
return "";
}
return getNamePool().getURI(nameCode);
}
/**
* Get the display name of this node. For elements and attributes this is [prefix:]localname.
* For unnamed nodes, it is an empty string.
*
* @return The display name of this node.
* For a node with no name, return an empty string.
*/
public String getDisplayName() {
int nameCode = getNameCode();
if (nameCode == -1) {
return "";
}
return getNamePool().getDisplayName(nameCode);
}
/**
* Get the local name of this node.
*
* @return The local name of this node.
* For a node with no name, return "",.
*/
public String getLocalPart() {
int nameCode = getNameCode();
if (nameCode == -1) {
return "";
}
return getNamePool().getLocalName(nameCode);
}
/**
* Get the line number of the node within its source document entity
*/
public int getLineNumber() {
return parent.getLineNumber();
}
/**
* Find the parent node of this node.
*
* @return The Node object describing the containing element or root node.
*/
public final NodeInfo getParent() {
return parent;
}
/**
* Get the previous sibling of the node
*
* @return The previous sibling node. Returns null if the current node is the first
* child of its parent.
*/
public NodeInfo getPreviousSibling() {
return parent.getNthChild(index - 1);
}
/**
* Get next sibling node
*
* @return The next sibling node of the required type. Returns null if the current node is the last
* child of its parent.
*/
public NodeInfo getNextSibling() {
return parent.getNthChild(index + 1);
}
/**
* Get first child - default implementation used for leaf nodes
*
* @return null
*/
public NodeInfo getFirstChild() {
return null;
}
/**
* Get last child - default implementation used for leaf nodes
*
* @return null
*/
public NodeInfo getLastChild() {
return null;
}
/**
* Return an enumeration over the nodes reached by the given axis from this node
*
* @param axisNumber The axis to be iterated over
* @return an AxisIterator that scans the nodes reached by the axis in turn.
*/
public AxisIterator iterateAxis(byte axisNumber) {
// Fast path for child axis
if (axisNumber == Axis.CHILD) {
if (this instanceof ParentNodeImpl) {
return ((ParentNodeImpl)this).enumerateChildren(null);
} else {
return EmptyIterator.getInstance();
}
} else {
return iterateAxis(axisNumber, AnyNodeTest.getInstance());
}
}
/**
* Return an enumeration over the nodes reached by the given axis from this node
*
* @param axisNumber The axis to be iterated over
* @param nodeTest A pattern to be matched by the returned nodes
* @return an AxisIterator that scans the nodes reached by the axis in turn.
*/
public AxisIterator iterateAxis(byte axisNumber, NodeTest nodeTest) {
switch (axisNumber) {
case Axis.ANCESTOR:
return new AncestorEnumeration(this, nodeTest, false);
case Axis.ANCESTOR_OR_SELF:
return new AncestorEnumeration(this, nodeTest, true);
case Axis.ATTRIBUTE:
if (getNodeKind() != Type.ELEMENT) {
return EmptyIterator.getInstance();
}
return new AttributeEnumeration(this, nodeTest);
case Axis.CHILD:
if (this instanceof ParentNodeImpl) {
return ((ParentNodeImpl)this).enumerateChildren(nodeTest);
} else {
return EmptyIterator.getInstance();
}
case Axis.DESCENDANT:
if (getNodeKind() == Type.DOCUMENT &&
nodeTest instanceof NameTest &&
nodeTest.getPrimitiveType() == Type.ELEMENT) {
return ((DocumentImpl)this).getAllElements(nodeTest.getFingerprint());
} else if (hasChildNodes()) {
return new DescendantEnumeration(this, nodeTest, false);
} else {
return EmptyIterator.getInstance();
}
case Axis.DESCENDANT_OR_SELF:
return new DescendantEnumeration(this, nodeTest, true);
case Axis.FOLLOWING:
return new FollowingEnumeration(this, nodeTest);
case Axis.FOLLOWING_SIBLING:
return new FollowingSiblingEnumeration(this, nodeTest);
case Axis.NAMESPACE:
if (getNodeKind() != Type.ELEMENT) {
return EmptyIterator.getInstance();
}
return NamespaceIterator.makeIterator(this, nodeTest);
case Axis.PARENT:
NodeInfo parent = getParent();
if (parent == null) {
return EmptyIterator.getInstance();
}
return Navigator.filteredSingleton(parent, nodeTest);
case Axis.PRECEDING:
return new PrecedingEnumeration(this, nodeTest);
case Axis.PRECEDING_SIBLING:
return new PrecedingSiblingEnumeration(this, nodeTest);
case Axis.SELF:
return Navigator.filteredSingleton(this, nodeTest);
case Axis.PRECEDING_OR_ANCESTOR:
return new PrecedingOrAncestorEnumeration(this, nodeTest);
default:
throw new IllegalArgumentException("Unknown axis number " + axisNumber);
}
}
/**
* Find the value of a given attribute of this node. <BR>
* This method is defined on all nodes to meet XSL requirements, but for nodes
* other than elements it will always return null.
* @param uri the namespace uri of an attribute
* @param localName the local name of an attribute
* @return the value of the attribute, if it exists, otherwise null
*/
// public String getAttributeValue( String uri, String localName ) {
// return null;
// }
/**
* Find the value of a given attribute of this node. <BR>
* This method is defined on all nodes to meet XSL requirements, but for nodes
* other than elements it will always return null.
* @param name the name of an attribute. This must be an unqualified attribute name,
* i.e. one with no namespace prefix.
* @return the value of the attribute, if it exists, otherwise null
*/
//public String getAttributeValue( String name ) {
// return null;
//}
/**
* Get the value of a given attribute of this node
*
* @param fingerprint The fingerprint of the attribute name
* @return the attribute value if it exists or null if not
*/
public String getAttributeValue(int fingerprint) {
return null;
}
/**
* Get the root node
*
* @return the NodeInfo representing the containing document
*/
public NodeInfo getRoot() {
return getDocumentRoot();
}
/**
* Get the root (document) node
*
* @return the DocumentInfo representing the containing document
*/
public DocumentInfo getDocumentRoot() {
return getParent().getDocumentRoot();
}
/**
* Get the next node in document order
*
* @param anchor the scan stops when it reaches a node that is not a descendant of the specified
* anchor node
* @return the next node in the document, or null if there is no such node
*/
public NodeImpl getNextInDocument(NodeImpl anchor) {
// find the first child node if there is one; otherwise the next sibling node
// if there is one; otherwise the next sibling of the parent, grandparent, etc, up to the anchor element.
// If this yields no result, return null.
NodeImpl next = (NodeImpl)getFirstChild();
if (next != null) {
return next;
}
if (this == anchor) {
return null;
}
next = (NodeImpl)getNextSibling();
if (next != null) {
return next;
}
NodeImpl parent = this;
while (true) {
parent = (NodeImpl)parent.getParent();
if (parent == null) {
return null;
}
if (parent == anchor) {
return null;
}
next = (NodeImpl)parent.getNextSibling();
if (next != null) {
return next;
}
}
}
/**
* Get the previous node in document order
*
* @return the previous node in the document, or null if there is no such node
*/
public NodeImpl getPreviousInDocument() {
// finds the last child of the previous sibling if there is one;
// otherwise the previous sibling element if there is one;
// otherwise the parent, up to the anchor element.
// If this reaches the document root, return null.
NodeImpl prev = (NodeImpl)getPreviousSibling();
if (prev != null) {
return prev.getLastDescendantOrSelf();
}
return (NodeImpl)getParent();
}
private NodeImpl getLastDescendantOrSelf() {
NodeImpl last = (NodeImpl)getLastChild();
if (last == null) {
return this;
}
return last.getLastDescendantOrSelf();
}
/**
* Get all namespace undeclarations and undeclarations defined on this element.
*
* @param buffer If this is non-null, and the result array fits in this buffer, then the result
* may overwrite the contents of this array, to avoid the cost of allocating a new array on the heap.
* @return An array of integers representing the namespace declarations and undeclarations present on
* this element. For a node other than an element, return null. Otherwise, the returned array is a
* sequence of namespace codes, whose meaning may be interpreted by reference to the name pool. The
* top half word of each namespace code represents the prefix, the bottom half represents the URI.
* If the bottom half is zero, then this is a namespace undeclaration rather than a declaration.
* The XML namespace is never included in the list. If the supplied array is larger than required,
* then the first unused entry will be set to -1.
* <p/>
* <p>For a node other than an element, the method returns null.</p>
*/
public int[] getDeclaredNamespaces(int[] buffer) {
return null;
}
/**
* Copy nodes. Copying type annotations is not yet supported for this tree
* structure, so we simply map the new interface onto the old
*/
// public final void copy(Receiver out, int whichNamespaces, boolean copyAnnotations, int locationId)
// throws XPathException {
// copy(out, whichNamespaces);
// }
//
// public abstract void copy(Receiver out, int whichNamespaces) throws XPathException;
// implement DOM Node methods
/**
* Determine whether the node has any children.
*
* @return <code>true</code> if the node has any children,
* <code>false</code> if the node has no children.
*/
public boolean hasChildNodes() {
return getFirstChild() != null;
}
}
//
// The contents of this file are subject to the Mozilla Public License Version 1.0 (the "License");
// you may not use this file except in compliance with the License. You may obtain a copy of the
// License at http://www.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations under the License.
//
// The Original Code is: all this file.
//
// The Initial Developer of the Original Code is Michael H. Kay.
//
// Portions created by (your name) are Copyright (C) (your legal entity). All Rights Reserved.
//
// Contributor(s): none.
//