| java.lang.Object
 org.apache.xml.utils.DOMHelper
All known Subclasses: org.apache.xml.utils.DOM2Helper,
| DOMHelper | | public class DOMHelper (Code) | | |
| Field Summary | |
| protected Document | m_DOMFactory
The factory object used for creating nodes
in the result tree. | | final protected static NSInfo | m_NSInfoNullNoAncestorXMLNS
Object to put into the m_NSInfos table that tells that a node has been
processed, and has no xmlns namespace decls. | | final protected static NSInfo | m_NSInfoNullWithXMLNS
Object to put into the m_NSInfos table that tells that a node has been
processed, and has xmlns namespace decls. | | final protected static NSInfo | m_NSInfoNullWithoutXMLNS
Object to put into the m_NSInfos table that tells that a node has been
processed, and has no xmlns namespace decls. | | final protected static NSInfo | m_NSInfoUnProcNoAncestorXMLNS
Object to put into the m_NSInfos table that tells that a node has not been
processed, and has no xmlns namespace decls, and has no ancestor decls. | | final protected static NSInfo | m_NSInfoUnProcWithXMLNS
Object to put into the m_NSInfos table that tells that a node has not been
processed, but has xmlns namespace decls. | | final protected static NSInfo | m_NSInfoUnProcWithoutXMLNS
Object to put into the m_NSInfos table that tells that a node has not been
processed, but has no xmlns namespace decls. | | Hashtable | m_NSInfos
An experiment for the moment. | | protected Vector | m_candidateNoAncestorXMLNS
Vector of node (odd indexes) and NSInfos (even indexes) that tell if
the given node is a candidate for ancestor namespace processing. |
| Method Summary | |
| public static Document | createDocument(boolean isSecureProcessing)
DOM Level 1 did not have a standard mechanism for creating a new
Document object. | | public static Document | createDocument()
DOM Level 1 did not have a standard mechanism for creating a new
Document object. | | public Document | getDOMFactory()
Retrieve the factory object required to create DOM nodes
in the result tree. | | public Element | getElementByID(String id, Document doc)
Given an ID, return the element. | | public String | getExpandedAttributeName(Attr attr)
Returns the attribute name with the namespace prefix (if any) replaced
by the Namespace URI it was bound to. | | public String | getExpandedElementName(Element elem)
Returns the element name with the namespace prefix (if any) replaced
by the Namespace URI it was bound to. | | public short | getLevel(Node n)
Get the depth level of this node in the tree (equals 1 for
a parentless node).
Parameters:
n - Node to be examined. | | public String | getLocalNameOfNode(Node n)
Returns the local name of the given node. | | public String | getNamespaceForPrefix(String prefix, Element namespaceContext)
Given an XML Namespace prefix and a context in which the prefix
is to be evaluated, return the Namespace Name this prefix was
bound to. | | public String | getNamespaceOfNode(Node n)
Returns the namespace of the given node. | | public static String | getNodeData(Node node)
Get the textual contents of the node. | | public static void | getNodeData(Node node, FastStringBuffer buf)
Retrieve the text content of a DOM subtree, appending it into a
user-supplied FastStringBuffer object. | | public static Node | getParentOfNode(Node node)
Obtain the XPath-model parent of a DOM node -- ownerElement for Attrs,
parent for other nodes. | | public Node | getRoot(Node node)
Get the first unparented node in the ancestor chain. | | public Node | getRootNode(Node n)
Get the root node of the document tree, regardless of
whether or not the node passed in is a document node.
TODO: This doesn't handle DocumentFragments or "orphaned" subtrees
-- it's currently returning ownerDocument even when the tree is
not actually part of the main Document tree. | | public String | getUniqueID(Node node)
Supports the XPath function GenerateID by returning a unique
identifier string for any given DOM Node.
Warning: The base implementation uses the Node object's hashCode(),
which is NOT guaranteed to be unique. | | public String | getUnparsedEntityURI(String name, Document doc)
The getUnparsedEntityURI function returns the URI of the unparsed
entity with the specified name in the same document as the context
node (see [3.3 Unparsed Entities]). | | public boolean | isIgnorableWhitespace(Text node)
Tell if the node is ignorable whitespace. | | public boolean | isNamespaceNode(Node n)
Test whether the given node is a namespace decl node. | | public static boolean | isNodeAfter(Node node1, Node node2)
Figure out whether node2 should be considered as being later
in the document than node1, in Document Order as defined
by the XPath model. | | public static boolean | isNodeTheSame(Node node1, Node node2)
Use DTMNodeProxy to determine whether two nodes are the same.
Parameters:
node1 - The first DOM node to compare.
Parameters:
node2 - The second DOM node to compare. | | public void | setDOMFactory(Document domFactory)
Store the factory object required to create DOM nodes
in the result tree. | | public boolean | shouldStripSourceNode(Node textNode)
Tells, through the combination of the default-space attribute
on xsl:stylesheet, xsl:strip-space, xsl:preserve-space, and the
xml:space attribute, whether or not extra whitespace should be stripped
from the node. |
| m_DOMFactory | | protected Document m_DOMFactory(Code) | | The factory object used for creating nodes
in the result tree.
|
| m_NSInfoNullNoAncestorXMLNS | | final protected static NSInfo m_NSInfoNullNoAncestorXMLNS(Code) | | Object to put into the m_NSInfos table that tells that a node has been
processed, and has no xmlns namespace decls. and has no ancestor decls.
|
| m_NSInfoNullWithXMLNS | | final protected static NSInfo m_NSInfoNullWithXMLNS(Code) | | Object to put into the m_NSInfos table that tells that a node has been
processed, and has xmlns namespace decls.
|
| m_NSInfoNullWithoutXMLNS | | final protected static NSInfo m_NSInfoNullWithoutXMLNS(Code) | | Object to put into the m_NSInfos table that tells that a node has been
processed, and has no xmlns namespace decls.
|
| m_NSInfoUnProcNoAncestorXMLNS | | final protected static NSInfo m_NSInfoUnProcNoAncestorXMLNS(Code) | | Object to put into the m_NSInfos table that tells that a node has not been
processed, and has no xmlns namespace decls, and has no ancestor decls.
|
| m_NSInfoUnProcWithXMLNS | | final protected static NSInfo m_NSInfoUnProcWithXMLNS(Code) | | Object to put into the m_NSInfos table that tells that a node has not been
processed, but has xmlns namespace decls.
|
| m_NSInfoUnProcWithoutXMLNS | | final protected static NSInfo m_NSInfoUnProcWithoutXMLNS(Code) | | Object to put into the m_NSInfos table that tells that a node has not been
processed, but has no xmlns namespace decls.
|
| m_candidateNoAncestorXMLNS | | protected Vector m_candidateNoAncestorXMLNS(Code) | | Vector of node (odd indexes) and NSInfos (even indexes) that tell if
the given node is a candidate for ancestor namespace processing.
|
| createDocument | | public static Document createDocument(boolean isSecureProcessing)(Code) | | DOM Level 1 did not have a standard mechanism for creating a new
Document object. This function provides a DOM-implementation-independent
abstraction for that for that concept. It's typically used when
outputting a new DOM as the result of an operation.
TODO: This isn't directly compatable with DOM Level 2.
The Level 2 createDocument call also creates the root
element, and thus requires that you know what that element will be
before creating the Document. We should think about whether we want
to change this code, and the callers, so we can use the DOM's own
method. (It's also possible that DOM Level 3 may relax this
sequence, but you may give up some intelligence in the DOM by
doing so; the intent was that knowing the document type and root
element might let the DOM automatically switch to a specialized
subclass for particular kinds of documents.)
Parameters:
isSecureProcessing - state of the secure processing feature. The newly created DOM Document object, with no children, ornull if we can't find a DOM implementation that permits creatingnew empty Documents. |
| createDocument | | public static Document createDocument()(Code) | | DOM Level 1 did not have a standard mechanism for creating a new
Document object. This function provides a DOM-implementation-independent
abstraction for that for that concept. It's typically used when
outputting a new DOM as the result of an operation.
The newly created DOM Document object, with no children, ornull if we can't find a DOM implementation that permits creatingnew empty Documents. |
| getDOMFactory | | public Document getDOMFactory()(Code) | | Retrieve the factory object required to create DOM nodes
in the result tree.
The result tree's DOM Document Node. |
| getElementByID | | public Element getElementByID(String id, Document doc)(Code) | | Given an ID, return the element. This can work only if the document
is interpreted in the context of a DTD or Schema, since otherwise
we don't know which attributes are or aren't IDs.
Note that DOM Level 1 had no ability to retrieve this information.
DOM Level 2 introduced it but does not promise that it will be
supported in all DOMs; those which can't support it will always
return null.
TODO: getElementByID is currently unimplemented. Support DOM Level 2?
Parameters:
id - The unique identifier to be searched for.
Parameters:
doc - The document to search within. CURRENTLY HARDCODED TO NULL, but it should be:The node which has this unique identifier, or null if thereis no such node or this DOM can't reliably recognize it. |
| getExpandedAttributeName | | public String getExpandedAttributeName(Attr attr)(Code) | | Returns the attribute name with the namespace prefix (if any) replaced
by the Namespace URI it was bound to. This is not a standard
representation of a node name, but it allows convenient
single-string comparison of the "universal" names of two nodes.
Parameters:
attr - Attr to be examined String in the form "namespaceURI:localname" if the nodebelongs to a namespace, or simply "localname" if it doesn't.
See Also: DOMHelper.getExpandedElementName |
| getExpandedElementName | | public String getExpandedElementName(Element elem)(Code) | | Returns the element name with the namespace prefix (if any) replaced
by the Namespace URI it was bound to. This is not a standard
representation of a node name, but it allows convenient
single-string comparison of the "universal" names of two nodes.
Parameters:
elem - Element to be examined. String in the form "namespaceURI:localname" if the nodebelongs to a namespace, or simply "localname" if it doesn't.
See Also: DOMHelper.getExpandedAttributeName |
| getLevel | | public short getLevel(Node n)(Code) | | Get the depth level of this node in the tree (equals 1 for
a parentless node).
Parameters:
n - Node to be examined. the number of ancestors, plus one |
| getLocalNameOfNode | | public String getLocalNameOfNode(Node n)(Code) | | Returns the local name of the given node. If the node's name begins
with a namespace prefix, this is the part after the colon; otherwise
it's the full node name.
Parameters:
n - the node to be examined. String containing the Local Name |
| getNamespaceForPrefix | | public String getNamespaceForPrefix(String prefix, Element namespaceContext)(Code) | | Given an XML Namespace prefix and a context in which the prefix
is to be evaluated, return the Namespace Name this prefix was
bound to. Note that DOM Level 3 is expected to provide a version of
this which deals with the DOM's "early binding" behavior.
Default handling:
Parameters:
prefix - String containing namespace prefix to be resolved, without the ':' which separates it from the localname when used in a Node Name. The empty sting signifies the default namespaceat this point in the document.
Parameters:
namespaceContext - Element which provides context for resolution.(We could extend this to work for other nodes by first seeking theirnearest Element ancestor.) a String containing the Namespace URI which this prefixrepresents in the specified context. |
| getNamespaceOfNode | | public String getNamespaceOfNode(Node n)(Code) | | Returns the namespace of the given node. Differs from simply getting
the node's prefix and using getNamespaceForPrefix in that it attempts
to cache some of the data in NSINFO objects, to avoid repeated lookup.
TODO: Should we consider moving that logic into getNamespaceForPrefix?
Parameters:
n - Node to be examined. String containing the Namespace Name (uri) for this node.Note that this is undefined for any nodes other than Elements andAttributes. |
| getNodeData | | public static String getNodeData(Node node)(Code) | | Get the textual contents of the node. See
getNodeData(Node,FastStringBuffer) for discussion of how
whitespace nodes are handled.
Parameters:
node - DOM Node to be examined String containing a concatenation of all the textual content within that node.
See Also: DOMHelper.getNodeData(Node,FastStringBuffer) |
| getNodeData | | public static void getNodeData(Node node, FastStringBuffer buf)(Code) | | Retrieve the text content of a DOM subtree, appending it into a
user-supplied FastStringBuffer object. Note that attributes are
not considered part of the content of an element.
There are open questions regarding whitespace stripping.
Currently we make no special effort in that regard, since the standard
DOM doesn't yet provide DTD-based information to distinguish
whitespace-in-element-context from genuine #PCDATA. Note that we
should probably also consider xml:space if/when we address this.
DOM Level 3 may solve the problem for us.
Parameters:
node - Node whose subtree is to be walked, gathering thecontents of all Text or CDATASection nodes.
Parameters:
buf - FastStringBuffer into which the contents of the textnodes are to be concatenated. |
| getParentOfNode | | public static Node getParentOfNode(Node node) throws RuntimeException(Code) | | Obtain the XPath-model parent of a DOM node -- ownerElement for Attrs,
parent for other nodes.
Background: The DOM believes that you must be your Parent's
Child, and thus Attrs don't have parents. XPath said that Attrs
do have their owning Element as their parent. This function
bridges the difference, either by using the DOM Level 2 ownerElement
function or by using a "silly and expensive function" in Level 1
DOMs.
(There's some discussion of future DOMs generalizing ownerElement
into ownerNode and making it work on all types of nodes. This
still wouldn't help the users of Level 1 or Level 2 DOMs)
Parameters:
node - Node whose XPath parent we want to obtain the parent of the node, or the ownerElement if it's anAttr node, or null if the node is an orphan.
throws:
RuntimeException - if the Document has no root element.This can't arise if the Document was createdvia the DOM Level 2 factory methods, but is possible if othermechanisms were used to obtain it |
| getRoot | | public Node getRoot(Node node)(Code) | | Get the first unparented node in the ancestor chain.
Parameters:
node - Starting node, to specify which chain to chase the topmost ancestor. |
| getRootNode | | public Node getRootNode(Node n)(Code) | | Get the root node of the document tree, regardless of
whether or not the node passed in is a document node.
TODO: This doesn't handle DocumentFragments or "orphaned" subtrees
-- it's currently returning ownerDocument even when the tree is
not actually part of the main Document tree. We should either
rewrite the description to say that it finds the Document node,
or change the code to walk up the ancestor chain.
Parameters:
n - Node to be examined the Document node. Note that this is not the correct answerif n was (or was a child of) a DocumentFragment or an orphaned node,as can arise if the DOM has been edited rather than being generatedby a parser. |
| getUniqueID | | public String getUniqueID(Node node)(Code) | | Supports the XPath function GenerateID by returning a unique
identifier string for any given DOM Node.
Warning: The base implementation uses the Node object's hashCode(),
which is NOT guaranteed to be unique. If that method hasn't been
overridden in this DOM ipmlementation, most Java implementions will
derive it from the object's address and should be OK... but if
your DOM uses a different definition of hashCode (eg hashing the
contents of the subtree), or if your DOM may have multiple objects
that represent a single Node in the data structure (eg via proxying),
you may need to find another way to assign a unique identifier.
Also, be aware that if nodes are destroyed and recreated, there is
an open issue regarding whether an ID may be reused. Currently
we're assuming that the input document is stable for the duration
of the XPath/XSLT operation, so this shouldn't arise in this context.
(DOM Level 3 is investigating providing a unique node "key", but
that won't help Level 1 and Level 2 implementations.)
Parameters:
node - whose identifier you want to obtain a string which should be different for every Node object. |
| getUnparsedEntityURI | | public String getUnparsedEntityURI(String name, Document doc)(Code) | | The getUnparsedEntityURI function returns the URI of the unparsed
entity with the specified name in the same document as the context
node (see [3.3 Unparsed Entities]). It returns the empty string if
there is no such entity.
XML processors may choose to use the System Identifier (if one
is provided) to resolve the entity, rather than the URI in the
Public Identifier. The details are dependent on the processor, and
we would have to support some form of plug-in resolver to handle
this properly. Currently, we simply return the System Identifier if
present, and hope that it a usable URI or that our caller can
map it to one.
TODO: Resolve Public Identifiers... or consider changing function name.
If we find a relative URI
reference, XML expects it to be resolved in terms of the base URI
of the document. The DOM doesn't do that for us, and it isn't
entirely clear whether that should be done here; currently that's
pushed up to a higher levelof our application. (Note that DOM Level
1 didn't store the document's base URI.)
TODO: Consider resolving Relative URIs.
(The DOM's statement that "An XML processor may choose to
completely expand entities before the structure model is passed
to the DOM" refers only to parsed entities, not unparsed, and hence
doesn't affect this function.)
Parameters:
name - A string containing the Entity Name of the unparsedentity.
Parameters:
doc - Document node for the document to be searched. String containing the URI of the Unparsed Entity, or anempty string if no such entity exists. |
| isIgnorableWhitespace | | public boolean isIgnorableWhitespace(Text node)(Code) | | Tell if the node is ignorable whitespace. Note that this can
be determined only in the context of a DTD or other Schema,
and that DOM Level 2 has nostandardized DOM API which can
return that information.
Parameters:
node - Node to be examined CURRENTLY HARDCODED TO FALSE, but should return true ifand only if the node is of type Text, contains only whitespace,and does not appear as part of the #PCDATA content of an element.(Note that determining this last may require allowing for Entity References.) |
| isNamespaceNode | | public boolean isNamespaceNode(Node n)(Code) | | Test whether the given node is a namespace decl node. In DOM Level 2
this can be done in a namespace-aware manner, but in Level 1 DOMs
it has to be done by testing the node name.
Parameters:
n - Node to be examined. boolean -- true iff the node is an Attr whose name is "xmlns" or has the "xmlns:" prefix. |
| isNodeAfter | | public static boolean isNodeAfter(Node node1, Node node2)(Code) | | Figure out whether node2 should be considered as being later
in the document than node1, in Document Order as defined
by the XPath model. This may not agree with the ordering defined
by other XML applications.
There are some cases where ordering isn't defined, and neither are
the results of this function -- though we'll generally return true.
TODO: Make sure this does the right thing with attribute nodes!!!
Parameters:
node1 - DOM Node to perform position comparison on.
Parameters:
node2 - DOM Node to perform position comparison on . false if node2 comes before node1, otherwise return true.You can think of this as (node1.documentOrderPosition <= node2.documentOrderPosition). |
| isNodeTheSame | | public static boolean isNodeTheSame(Node node1, Node node2)(Code) | | Use DTMNodeProxy to determine whether two nodes are the same.
Parameters:
node1 - The first DOM node to compare.
Parameters:
node2 - The second DOM node to compare. true if the two nodes are the same. |
| setDOMFactory | | public void setDOMFactory(Document domFactory)(Code) | | Store the factory object required to create DOM nodes
in the result tree. In fact, that's just the result tree's
Document node...
Parameters:
domFactory - The DOM Document Node within whose contextthe result tree will be built. |
| shouldStripSourceNode | | public boolean shouldStripSourceNode(Node textNode) throws javax.xml.transform.TransformerException(Code) | | Tells, through the combination of the default-space attribute
on xsl:stylesheet, xsl:strip-space, xsl:preserve-space, and the
xml:space attribute, whether or not extra whitespace should be stripped
from the node. Literal elements from template elements should
not be tested with this function.
Parameters:
textNode - A text node from the source tree. true if the text node should be stripped of extra whitespace.
throws:
javax.xml.transform.TransformerException - |
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