weka.core.xml
Class XMLDocument

java.lang.Object
  weka.core.xml.XMLDocument

All Implemented Interfaces:

RevisionHandler

Direct Known Subclasses:

XMLInstances

public class XMLDocument
extends Object
implements RevisionHandler

This class offers some methods for generating, reading and writing XML documents.
It can only handle UTF-8.

Version:

$Revision: 8034 $

Author:

FracPete (fracpete at waikato dot ac dot nz)

See Also:

PI

Field Summary

static String	ATT_NAME the "name" attribute.
static String	ATT_VERSION the "version" attribute.
static String	DTD_ANY the ANY placeholder.
static String	DTD_AT_LEAST_ONE the at least one marker.
static String	DTD_ATTLIST the AttList definition.
static String	DTD_CDATA the CDATA placeholder.
static String	DTD_DOCTYPE the DocType definition.
static String	DTD_ELEMENT the Element definition.
static String	DTD_IMPLIED the #IMPLIED placeholder.
static String	DTD_OPTIONAL the optional marker.
static String	DTD_PCDATA the #PCDATA placeholder.
static String	DTD_REQUIRED the #REQUIRED placeholder.
static String	DTD_SEPARATOR the option separator.
static String	DTD_ZERO_OR_MORE the zero or more marker.
static String	PI the parsing instructions "<?xml version=\"1.0\" encoding=\"utf-8\"?>" (may not show up in Javadoc due to tags!).
static String	VAL_NO the value "no".
static String	VAL_YES the value "yes".

Constructor Summary

XMLDocument()
initializes the factory with non-validating parser.

XMLDocument(File file)
Creates a new instance of XMLDocument.

XMLDocument(InputStream stream)
Creates a new instance of XMLDocument.

XMLDocument(Reader reader)
Creates a new instance of XMLDocument.

XMLDocument(String xml)
Creates a new instance of XMLDocument.

Method Summary

void	clear() sets up an empty DOM document, with the current DOCTYPE and root node.
Boolean	evalBoolean(String xpath) Evaluates and returns the boolean result of the XPath expression.
Double	evalDouble(String xpath) Evaluates and returns the double result of the XPath expression.
String	evalString(String xpath) Evaluates and returns the boolean result of the XPath expression.
NodeList	findNodes(String xpath) Returns the nodes that the given xpath expression will find in the document.
DocumentBuilder	getBuilder() returns the DocumentBuilder.
static Vector<Element>	getChildTags(Node parent) returns all non tag-children from the given node.
static Vector<Element>	getChildTags(Node parent, String name) returns all non tag-children from the given node.
static String	getContent(Element node) returns the text between the opening and closing tag of a node (performs a trim() on the result).
String	getDocType() returns the current DOCTYPE, can be null.
Document	getDocument() returns the parsed DOM document.
DocumentBuilderFactory	getFactory() returns the DocumentBuilderFactory.
Node	getNode(String xpath) Returns the node represented by the XPath expression.
String	getRevision() Returns the revision string.
String	getRootNode() returns the current root node.
boolean	getValidating() returns whether a validating parser is used.
static void	main(String[] args) for testing only.
Document	newDocument(String docType, String rootNode) creates a new Document with the given information.
void	print() prints the current DOM document to standard out.
Document	read(File file) parses the given file and returns a DOM document.
Document	read(InputStream stream) parses the given stream and returns a DOM document.
Document	read(Reader reader) parses the given reader and returns a DOM document.
Document	read(String xml) parses the given XML string (can be XML or a filename) and returns a DOM Document.
void	setDocType(String docType) sets the DOCTYPE-String to use in the XML output.
void	setDocument(Document newDocument) sets the DOM document to use.
void	setRootNode(String rootNode) sets the root node to use in the XML output.
void	setValidating(boolean validating) sets whether to use a validating parser or not. Note: this does clear the current DOM document!
String	toString() returns the current DOM document as XML-string.
void	write(File file) writes the current DOM document into the given file.
void	write(OutputStream stream) writes the current DOM document into the given stream.
void	write(String file) writes the current DOM document into the given file.
void	write(Writer writer) writes the current DOM document into the given writer.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

PI

public static final String PI

the parsing instructions "<?xml version=\"1.0\" encoding=\"utf-8\"?>" (may not show up in Javadoc due to tags!).

See Also:

Constant Field Values

DTD_DOCTYPE

public static final String DTD_DOCTYPE

the DocType definition.

See Also:

Constant Field Values

DTD_ELEMENT

public static final String DTD_ELEMENT

the Element definition.

See Also:

Constant Field Values

DTD_ATTLIST

public static final String DTD_ATTLIST

the AttList definition.

See Also:

Constant Field Values

DTD_OPTIONAL

public static final String DTD_OPTIONAL

the optional marker.

See Also:

Constant Field Values

DTD_AT_LEAST_ONE

public static final String DTD_AT_LEAST_ONE

the at least one marker.

See Also:

Constant Field Values

DTD_ZERO_OR_MORE

public static final String DTD_ZERO_OR_MORE

the zero or more marker.

See Also:

Constant Field Values

DTD_SEPARATOR

public static final String DTD_SEPARATOR

the option separator.

See Also:

Constant Field Values

DTD_CDATA

public static final String DTD_CDATA

the CDATA placeholder.

See Also:

Constant Field Values

DTD_ANY

public static final String DTD_ANY

the ANY placeholder.

See Also:

Constant Field Values

DTD_PCDATA

public static final String DTD_PCDATA

the #PCDATA placeholder.

See Also:

Constant Field Values

DTD_IMPLIED

public static final String DTD_IMPLIED

the #IMPLIED placeholder.

See Also:

Constant Field Values

DTD_REQUIRED

public static final String DTD_REQUIRED

the #REQUIRED placeholder.

See Also:

Constant Field Values

ATT_VERSION

public static final String ATT_VERSION

the "version" attribute.

See Also:

Constant Field Values

ATT_NAME

public static final String ATT_NAME

the "name" attribute.

See Also:

Constant Field Values

VAL_YES

public static final String VAL_YES

the value "yes".

See Also:

Constant Field Values

VAL_NO

public static final String VAL_NO

the value "no".

See Also:

Constant Field Values

Constructor Detail

XMLDocument

public XMLDocument()
            throws Exception

initializes the factory with non-validating parser.

Throws:

Exception - if the construction fails

XMLDocument

public XMLDocument(String xml)
            throws Exception

Creates a new instance of XMLDocument.

Parameters:

xml - the xml to parse (if "Throws:

Exception - if the construction of the DocumentBuilder fails

See Also:

setValidating(boolean)

XMLDocument

public XMLDocument(File file)
            throws Exception

Creates a new instance of XMLDocument.

Parameters:

file - the XML file to parse

Throws:

Exception - if the construction of the DocumentBuilder fails

See Also:

setValidating(boolean)

XMLDocument

public XMLDocument(InputStream stream)
            throws Exception

Creates a new instance of XMLDocument.

Parameters:

stream - the XML stream to parse

Throws:

Exception - if the construction of the DocumentBuilder fails

See Also:

setValidating(boolean)

XMLDocument

public XMLDocument(Reader reader)
            throws Exception

Creates a new instance of XMLDocument.

Parameters:

reader - the XML reader to parse

Throws:

Exception - if the construction of the DocumentBuilder fails

See Also:

setValidating(boolean)

Method Detail

getFactory

public DocumentBuilderFactory getFactory()

returns the DocumentBuilderFactory.

Returns:

the DocumentBuilderFactory

getBuilder

public DocumentBuilder getBuilder()

returns the DocumentBuilder.

Returns:

the DocumentBuilder

getValidating

public boolean getValidating()

returns whether a validating parser is used.

Returns:

whether a validating parser is used

setValidating

public void setValidating(boolean validating)
                   throws Exception

sets whether to use a validating parser or not.
Note: this does clear the current DOM document!

Parameters:

validating - whether to use a validating parser

Throws:

Exception - if the instantiating of the DocumentBuilder fails

getDocument

public Document getDocument()

returns the parsed DOM document.

Returns:

the parsed DOM document

setDocument

public void setDocument(Document newDocument)

sets the DOM document to use.

Parameters:

newDocument - the DOM document to use

setDocType

public void setDocType(String docType)

sets the DOCTYPE-String to use in the XML output. Performs NO checking! if it is null the DOCTYPE is omitted.

Parameters:

docType - the DOCTYPE definition to use in XML output

getDocType

public String getDocType()

returns the current DOCTYPE, can be null.

Returns:

the current DOCTYPE definition, can be null

setRootNode

public void setRootNode(String rootNode)

sets the root node to use in the XML output. Performs NO checking with DOCTYPE!

Parameters:

rootNode - the root node to use in the XML output

getRootNode

public String getRootNode()

returns the current root node.

Returns:

the current root node

clear

public void clear()

sets up an empty DOM document, with the current DOCTYPE and root node.

See Also:

setRootNode(String), setDocType(String)

newDocument

public Document newDocument(String docType,
                            String rootNode)

creates a new Document with the given information.

Parameters:

docType - the DOCTYPE definition (no checking happens!), can be null

rootNode - the name of the root node (must correspond to the one given in docType)

Returns:

returns the just created DOM document for convenience

read

public Document read(String xml)
              throws Exception

parses the given XML string (can be XML or a filename) and returns a DOM Document.

Parameters:

xml - the xml to parse (if "Returns:

the parsed DOM document

Throws:

Exception - if something goes wrong with the parsing

read

public Document read(File file)
              throws Exception

parses the given file and returns a DOM document.

Parameters:

file - the XML file to parse

Returns:

the parsed DOM document

Throws:

Exception - if something goes wrong with the parsing

read

public Document read(InputStream stream)
              throws Exception

parses the given stream and returns a DOM document.

Parameters:

stream - the XML stream to parse

Returns:

the parsed DOM document

Throws:

Exception - if something goes wrong with the parsing

read

public Document read(Reader reader)
              throws Exception

parses the given reader and returns a DOM document.

Parameters:

reader - the XML reader to parse

Returns:

the parsed DOM document

Throws:

Exception - if something goes wrong with the parsing

write

public void write(String file)
           throws Exception

writes the current DOM document into the given file.

Parameters:

file - the filename to write to

Throws:

Exception - if something goes wrong with the parsing

write

public void write(File file)
           throws Exception

writes the current DOM document into the given file.

Parameters:

file - the filename to write to

Throws:

Exception - if something goes wrong with the parsing

write

public void write(OutputStream stream)
           throws Exception

writes the current DOM document into the given stream.

Parameters:

stream - the filename to write to

Throws:

Exception - if something goes wrong with the parsing

write

public void write(Writer writer)
           throws Exception

writes the current DOM document into the given writer.

Parameters:

writer - the filename to write to

Throws:

Exception - if something goes wrong with the parsing

getChildTags

public static Vector<Element> getChildTags(Node parent)

returns all non tag-children from the given node.

Parameters:

parent - the node to get the children from

Returns:

a vector containing all the non-text children

getChildTags

public static Vector<Element> getChildTags(Node parent,
                                           String name)

returns all non tag-children from the given node.

Parameters:

parent - the node to get the children from

name - the name of the tags to return, "" for all

Returns:

a vector containing all the non-text children

findNodes

public NodeList findNodes(String xpath)

Returns the nodes that the given xpath expression will find in the document. Can return null if an error occurred.

Parameters:

xpath - the XPath expression to run on the document

Returns:

the nodelist

getNode

public Node getNode(String xpath)

Returns the node represented by the XPath expression. Can return null if an error occurred.

Parameters:

xpath - the XPath expression to run on the document

Returns:

the node

evalBoolean

public Boolean evalBoolean(String xpath)

Evaluates and returns the boolean result of the XPath expression.

Parameters:

xpath - the expression to evaluate

Returns:

the result of the evaluation, null in case of an error

evalDouble

public Double evalDouble(String xpath)

Evaluates and returns the double result of the XPath expression.

Parameters:

xpath - the expression to evaluate

Returns:

the result of the evaluation, null in case of an error

evalString

public String evalString(String xpath)

Evaluates and returns the boolean result of the XPath expression.

Parameters:

xpath - the expression to evaluate

Returns:

the result of the evaluation

getContent

public static String getContent(Element node)

returns the text between the opening and closing tag of a node (performs a trim() on the result).

Parameters:

node - the node to get the text from

Returns:

the content of the given node

print

public void print()

prints the current DOM document to standard out.

toString

public String toString()

returns the current DOM document as XML-string.

Overrides:

toString in class Object

Returns:

the document as XML-string representation

getRevision

public String getRevision()

Returns the revision string.

Specified by:

getRevision in interface RevisionHandler

Returns:

the revision

main

public static void main(String[] args)
                 throws Exception

for testing only. takes the name of an XML file as first arg, reads that file, prints it to stdout and if a second filename is given, writes the parsed document to that again.

Parameters:

args - the commandline arguments

Throws:

Exception - if something goes wrong