org.progeeks.util.xml
Class XmlReader

java.lang.Object
  org.progeeks.util.xml.XmlReader

Direct Known Subclasses:

ObjectXmlReader, SimpleXmlReader, XmlSignatureReader

public class XmlReader
extends java.lang.Object

Provides base support for reading XML files into objects as defined by subclass implementations. This class acts as an adatper between the SAX HandlerBase class and slightly more subclass friendly version. This class is designed to work with JAXP 1.0, ie: SAX1... I don't want to break compatability yet so using a newer version of JAXP will work, but will generate deprecation warnings.

This base class implementation also provides a simple kind of tag handler support that allows subclasses to simple register the appropriate handler objects for reading certain tag types.

Since:

1.0

Version:

$Revision: 1.18 $

Author:

Paul Speed

Nested Class Summary

protected class

XmlReader.XmlHandler HandlerBase implementation that interacts with the outer class.

Constructor Summary

XmlReader()

Method Summary

protected void	addTagText(java.lang.String name, java.lang.String newText, java.lang.StringBuffer accumulatedText, java.lang.Object object) Called when new text is parsed within a tag body.
protected XmlException	createXmlException(java.lang.String message) Creates a properly "located" XmlException using the getLocation() method.
protected XmlException	createXmlException(java.lang.String message, java.lang.Throwable cause) Creates a properly "located" XmlException using the getLocation() method.
protected void	endTag(java.lang.String name, java.lang.String text, java.lang.Object object) Called when the end of a tag is reached.
static java.util.Map	getAttributesAsMap(org.xml.sax.Attributes atts) Converts the specified Attributes object to a Map.
protected java.lang.Object	getCurrentObject() Returns the last object that was created during a startTag() method.
protected org.xml.sax.Locator	getDocumentLocator() Returns a locator object that can be used to determine information about the current file position.
protected boolean	getIgnoreTagCase() Returns the tag name case sensitivity policy for looking up tag handlers.
protected java.lang.String	getLocation() Returns the current location as a formatted string.
protected java.lang.Object	getPreviousObject() Returns the object that was created two calls startTag() ago.
protected java.lang.Object	getRootObject() Returns the root object on the stack.
protected int	getStackSize() Returns the current tag object stack size.
protected TagReader	getTagReader(java.lang.String tagName)
java.lang.Object	readObject(java.io.Reader in) Implemented by subclasses to provide read support.
protected void	readXml(org.w3c.dom.Document document) Called by subclasses to read XML in from the supplied document.
protected void	readXml(org.w3c.dom.Document document, javax.xml.transform.Transformer transformer) Called by subclasses to read XML in from the supplied document after applying the given transformation.
protected void	readXml(java.io.Reader in) Called by the subclass implementation to load data from the specified reader.
protected void	registerHandler(java.lang.String tagName, TagReader tagReader) Registers the specified handler object to handle tags of the specified tag name.
protected void	replaceCurrentObject(java.lang.Object object) Replaces the last object that was create during a startTag().
protected void	reset() Resets the internal data structures before reading another object.
protected org.xml.sax.InputSource	resolveEntity(java.lang.String publicId, java.lang.String systemId)
protected void	setDefaultHandler(TagReader defaultHandler) Sets a default handler that will be used when a better handler cannot be found.
protected void	setIgnoreTagCase(boolean bool) Sets the tag name case sensitivity policy for looking up tag handlers.
protected java.lang.Object	startTag(java.lang.String name, org.xml.sax.Attributes atts) Called at the beginning of a new tag.

Methods inherited from class java.lang.Object

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

Constructor Detail

XmlReader

public XmlReader()

Method Detail

readObject

public java.lang.Object readObject(java.io.Reader in)
                            throws java.io.IOException

Implemented by subclasses to provide read support. This is an optional operation since some xml reader implementations will only read from a single reader. Eventually we may want to break this out into a ReusableXmlReader interface or something.

Throws:

java.io.IOException

reset

protected void reset()

Resets the internal data structures before reading another object. This should be called by readObject().

setIgnoreTagCase

protected void setIgnoreTagCase(boolean bool)

Sets the tag name case sensitivity policy for looking up tag handlers. True means that case is ignored when looking up handlers.

getIgnoreTagCase

protected boolean getIgnoreTagCase()

Returns the tag name case sensitivity policy for looking up tag handlers.

setDefaultHandler

protected void setDefaultHandler(TagReader defaultHandler)

Sets a default handler that will be used when a better handler cannot be found.

registerHandler

protected void registerHandler(java.lang.String tagName,
                               TagReader tagReader)

Registers the specified handler object to handle tags of the specified tag name.

getTagReader

protected TagReader getTagReader(java.lang.String tagName)

startTag

protected java.lang.Object startTag(java.lang.String name,
                                    org.xml.sax.Attributes atts)
                             throws org.xml.sax.SAXException

Called at the beginning of a new tag. The implementation class can use the supplied data to instantiate an object and return it. After this method, the returned object will be the new value returned by getCurrentObject(). The default implementation of this method searches for the tag handler object associated with the specified tag name and uses that to process the attribute list.

Throws:

org.xml.sax.SAXException

addTagText

protected void addTagText(java.lang.String name,
                          java.lang.String newText,
                          java.lang.StringBuffer accumulatedText,
                          java.lang.Object object)
                   throws org.xml.sax.SAXException

Called when new text is parsed within a tag body.

Throws:

org.xml.sax.SAXException

endTag

protected void endTag(java.lang.String name,
                      java.lang.String text,
                      java.lang.Object object)
               throws org.xml.sax.SAXException

Called when the end of a tag is reached.

Throws:

org.xml.sax.SAXException

getDocumentLocator

protected org.xml.sax.Locator getDocumentLocator()

Returns a locator object that can be used to determine information about the current file position.

getCurrentObject

protected java.lang.Object getCurrentObject()

Returns the last object that was created during a startTag() method.

replaceCurrentObject

protected void replaceCurrentObject(java.lang.Object object)

Replaces the last object that was create during a startTag().

getPreviousObject

protected java.lang.Object getPreviousObject()

Returns the object that was created two calls startTag() ago. This should be the parent of the current object.

getStackSize

protected int getStackSize()

Returns the current tag object stack size.

getRootObject

protected java.lang.Object getRootObject()

Returns the root object on the stack.

getLocation

protected java.lang.String getLocation()

Returns the current location as a formatted string.

createXmlException

protected XmlException createXmlException(java.lang.String message)

Creates a properly "located" XmlException using the getLocation() method.

createXmlException

protected XmlException createXmlException(java.lang.String message,
                                          java.lang.Throwable cause)

Creates a properly "located" XmlException using the getLocation() method.

getAttributesAsMap

public static java.util.Map getAttributesAsMap(org.xml.sax.Attributes atts)

Converts the specified Attributes object to a Map. This is mostly to allow easy insertion into exceptions and log messages since some information is actually lost.

readXml

protected void readXml(java.io.Reader in)
                throws java.io.IOException,
                       XmlException

Called by the subclass implementation to load data from the specified reader.

Throws:

java.io.IOException

XmlException

readXml

protected void readXml(org.w3c.dom.Document document)
                throws XmlException

Called by subclasses to read XML in from the supplied document.

Throws:

XmlException

readXml

protected void readXml(org.w3c.dom.Document document,
                       javax.xml.transform.Transformer transformer)
                throws XmlException

Called by subclasses to read XML in from the supplied document after applying the given transformation.

Throws:

XmlException

resolveEntity

protected org.xml.sax.InputSource resolveEntity(java.lang.String publicId,
                                                java.lang.String systemId)
                                         throws org.xml.sax.SAXException

Throws:

org.xml.sax.SAXException