xtom.parser
Class Parser

java.lang.Object
  org.xml.sax.helpers.DefaultHandler
      xtom.parser.Parser

All Implemented Interfaces:

org.xml.sax.ContentHandler, org.xml.sax.DTDHandler, org.xml.sax.EntityResolver, org.xml.sax.ErrorHandler

public final class Parser

extends org.xml.sax.helpers.DefaultHandler

Description: This is a main parser that will be responsible for parsing XML string into an XMLTree.
This class will use Java 1.4 SAX Parser to construct a tree.

Version:

$Revision: 1.2 $

Author:

taras

Field Summary

private static Element	current
private java.lang.Exception	ex
private java.io.InputStream	in
private java.util.logging.Logger	logger
private static java.io.Writer	out
private static Element	previous
private static Element	root
private XMLTree	tree
private java.lang.String	xml

Constructor Summary

private	Parser()
	Parser(java.io.InputStream stream) Default parser.
	Parser(java.lang.String xml) Default parser.

Method Summary

void	addHandler(java.util.logging.Handler h) Adds a handler to the current logger.
void	characters(char[] buf, int offset, int len)
void	endElement(java.lang.String namespaceURI, java.lang.String sName, java.lang.String qName)
java.lang.Exception	getException()
XMLTree	getXMLTree() The tree is saved in memory for as long as Parser lives.
private void	logException(java.lang.Exception e) Logs the exception to the specified Handler
XMLTree	parse() Main Parser method This parser only checks if the xml is well formed, meaning that each tag has a closing tag.
private void	parse(java.io.InputStream in) This is the method that will do actual parsing.
void	setLoggingLevel(java.util.logging.Level l) Sets the level for Logging Default Logging Level is WARNING
private void	setUpLogging() Sets up the Logging for the Parser.
void	startElement(java.lang.String namespaceURI, java.lang.String sName, java.lang.String qName, org.xml.sax.Attributes attrs)

Methods inherited from class org.xml.sax.helpers.DefaultHandler

endDocument, endPrefixMapping, error, fatalError, ignorableWhitespace, notationDecl, processingInstruction, resolveEntity, setDocumentLocator, skippedEntity, startDocument, startPrefixMapping, unparsedEntityDecl, warning

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

logger

private java.util.logging.Logger logger

xml

private java.lang.String xml

tree

private XMLTree tree

in

private java.io.InputStream in

current

private static Element current

previous

private static Element previous

root

private static Element root

out

private static java.io.Writer out

ex

private java.lang.Exception ex

Constructor Detail

Parser

private Parser()

Parser

public Parser(java.lang.String xml)

Default parser. checks to see if the XML passed is not null and is at least 4 characters long, minimal xml . Sets the Default Logging Level and a Default Handler.

Parameters:

xml - xml string that must be parsed.

Throws:

java.lang.IllegalArgumentException - if the String is NULL or is less than 4 characters.

Parser

public Parser(java.io.InputStream stream)

Default parser. Reads the input stream. It only performs one check to see if the InputStream is not NULL. This constructor is provided as a convenience constructor.

Parameters:

stream - The Stream of XML Data.

Throws:

java.lang.IllegalArgumentException - if the InputStream was NULL.

Method Detail

setUpLogging

private void setUpLogging()

Sets up the Logging for the Parser. The J2SE 1.4 Logger is used.
Default Logger Level is OFF. This could be changed by using setLoggingLevel method.
The Default Handler is a ConsoleHandler. This could be changed by using addHandler method.

parse

public XMLTree parse()

Main Parser method
This parser only checks if the xml is well formed, meaning that each tag has a closing tag. It does not verify if the xml is valid.

Throws:

ParserIOException - if there was a problem parsing xml.

java.lang.UnsupportedOperationException - if any other excetion other then IO is thrown. This should not happen.

MissingRootElementException - if a root element was NULL after the parsing occured.

parse

private void parse(java.io.InputStream in)
            throws java.lang.Exception

This is the method that will do actual parsing.

Throws:

java.lang.Exception

getXMLTree

public XMLTree getXMLTree()

The tree is saved in memory for as long as Parser lives. The XML is guarenteed to be the same since the XML argument in the constructor is final.

Returns:

the xml tree, null, if the XML has not been parsed yet.

startElement

public void startElement(java.lang.String namespaceURI,
                         java.lang.String sName,
                         java.lang.String qName,
                         org.xml.sax.Attributes attrs)
                  throws org.xml.sax.SAXException

Parameters:

namespaceURI -

sName -

qName -

attrs -

Throws:

org.xml.sax.SAXException

See Also:

ContentHandler.startElement(java.lang.String, java.lang.String, java.lang.String, org.xml.sax.Attributes)

endElement

public void endElement(java.lang.String namespaceURI,
                       java.lang.String sName,
                       java.lang.String qName)
                throws org.xml.sax.SAXException

Throws:

org.xml.sax.SAXException

See Also:

ContentHandler.endElement(java.lang.String, java.lang.String, java.lang.String)

characters

public void characters(char[] buf,
                       int offset,
                       int len)
                throws org.xml.sax.SAXException

Throws:

org.xml.sax.SAXException

See Also:

ContentHandler.characters(char[], int, int)

getException

public java.lang.Exception getException()

Returns:

Returns the exception generated by the parser.

addHandler

public void addHandler(java.util.logging.Handler h)

Adds a handler to the current logger. Default Hanlder is ConsoleHanlder.

Parameters:

h - The handler.

setLoggingLevel

public void setLoggingLevel(java.util.logging.Level l)

Sets the level for Logging Default Logging Level is WARNING

Parameters:

l -

logException

private void logException(java.lang.Exception e)

Logs the exception to the specified Handler

Parameters:

e - Exception to be logged. If exception is null, it exits