org.apache.jackrabbit.commons.xml

Class SerializingContentHandler

java.lang.Object

org.xml.sax.helpers.DefaultHandler

org.apache.jackrabbit.commons.xml.DefaultContentHandler

org.apache.jackrabbit.commons.xml.SerializingContentHandler

All Implemented Interfaces:

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

public class SerializingContentHandler
extends DefaultContentHandler

A ContentHandler that serializes SAX events to a given Result instance. The JAXP SAXTransformerFactory facility is used for the serialization.

This class explicitly ensures that all namespace prefixes are also present as xmlns attributes in the serialized XML document. This avoids problems with Xalan's serialization behaviour which was (at least during JDK 1.4) to ignore namespaces if they were not present as xmlns attributes.

NOTE: The code in this class was originally written for Apache Cocoon and is included with some modifications here in Apache Jackrabbit. See the org.apache.cocoon.serialization.AbstractTextSerializer class in the cocoon-pipeline-impl component for the original code.

Since:

Jackrabbit JCR Commons 1.5

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	ENCODING The character encoding used for serialization (UTF-8).

Method Summary

Modifier and Type	Method and Description
void	endDocument() Delegated to DefaultContentHandler.handler.
void	endElement(java.lang.String eltUri, java.lang.String eltLocalName, java.lang.String eltQName) Receive notification of the end of an element.
void	endPrefixMapping(java.lang.String prefix) End the scope of a prefix-URI mapping: remove entry from mapping tables.
static org.xml.sax.helpers.DefaultHandler	getSerializer(java.io.OutputStream output) Creates a serializing content handler that writes to the given stream.
static org.xml.sax.helpers.DefaultHandler	getSerializer(javax.xml.transform.Result result) Creates a serializing content handler that writes to the given result.
static org.xml.sax.helpers.DefaultHandler	getSerializer(java.io.Writer writer) Creates a serializing content handler that writes to the given writer.
void	startDocument() Delegated to DefaultContentHandler.handler.
void	startElement(java.lang.String eltUri, java.lang.String eltLocalName, java.lang.String eltQName, org.xml.sax.Attributes attrs) Ensure all namespace declarations are present as xmlns: attributes and add those needed before calling superclass.
void	startPrefixMapping(java.lang.String prefix, java.lang.String uri) Track mappings to be able to add xmlns: attributes in startElement().

Methods inherited from class org.apache.jackrabbit.commons.xml.DefaultContentHandler

characters, ignorableWhitespace, processingInstruction, setDocumentLocator, skippedEntity

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

error, fatalError, notationDecl, resolveEntity, unparsedEntityDecl, warning

Methods inherited from class java.lang.Object

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

Field Detail

ENCODING

public static final java.lang.String ENCODING

The character encoding used for serialization (UTF-8). The encoding is fixed to make the text/xml content type safer to use.

See Also:

JCR-1621, Constant Field Values

Method Detail

getSerializer

public static org.xml.sax.helpers.DefaultHandler getSerializer(java.io.OutputStream output)
                                                        throws org.xml.sax.SAXException

Creates a serializing content handler that writes to the given stream.

Parameters:

output - serialization target

Returns:

serializing content handler

Throws:

org.xml.sax.SAXException - if the content handler could not be initialized

getSerializer

public static org.xml.sax.helpers.DefaultHandler getSerializer(java.io.Writer writer)
                                                        throws org.xml.sax.SAXException

Creates a serializing content handler that writes to the given writer.

Parameters:

writer - serialization target

Returns:

serializing content handler

Throws:

org.xml.sax.SAXException - if the content handler could not be initialized

getSerializer

public static org.xml.sax.helpers.DefaultHandler getSerializer(javax.xml.transform.Result result)
                                                        throws org.xml.sax.SAXException

Creates a serializing content handler that writes to the given result.

Parameters:

result - serialization target

Returns:

serializing content handler

Throws:

org.xml.sax.SAXException - if the content handler could not be initialized

startDocument

public void startDocument()
                   throws org.xml.sax.SAXException

Description copied from class: DefaultContentHandler

Delegated to DefaultContentHandler.handler.

Specified by:

startDocument in interface org.xml.sax.ContentHandler

Overrides:

startDocument in class DefaultContentHandler

Throws:

org.xml.sax.SAXException - if an error occurs

startPrefixMapping

public void startPrefixMapping(java.lang.String prefix,
                               java.lang.String uri)
                        throws org.xml.sax.SAXException

Track mappings to be able to add xmlns: attributes in startElement().

Specified by:

startPrefixMapping in interface org.xml.sax.ContentHandler

Overrides:

startPrefixMapping in class DefaultContentHandler

Parameters:

prefix - passed through

uri - passed through

Throws:

org.xml.sax.SAXException - if an error occurs

startElement

public void startElement(java.lang.String eltUri,
                         java.lang.String eltLocalName,
                         java.lang.String eltQName,
                         org.xml.sax.Attributes attrs)
                  throws org.xml.sax.SAXException

Ensure all namespace declarations are present as xmlns: attributes and add those needed before calling superclass. This is a workaround for a Xalan bug (at least in version 2.0.1) : org.apache.xalan.serialize.SerializerToXML ignores start/endPrefixMapping().

Specified by:

startElement in interface org.xml.sax.ContentHandler

Overrides:

startElement in class DefaultContentHandler

Parameters:

eltUri - passed through

eltLocalName - passed through

eltQName - passed through

attrs - passed through

Throws:

org.xml.sax.SAXException - if an error occurs

endElement

public void endElement(java.lang.String eltUri,
                       java.lang.String eltLocalName,
                       java.lang.String eltQName)
                throws org.xml.sax.SAXException

Receive notification of the end of an element. Try to restore the element qName.

Specified by:

endElement in interface org.xml.sax.ContentHandler

Overrides:

endElement in class DefaultContentHandler

Parameters:

eltUri - passed through

eltLocalName - passed through

eltQName - passed through

Throws:

org.xml.sax.SAXException - if an error occurs

endPrefixMapping

public void endPrefixMapping(java.lang.String prefix)
                      throws org.xml.sax.SAXException

End the scope of a prefix-URI mapping: remove entry from mapping tables.

Specified by:

endPrefixMapping in interface org.xml.sax.ContentHandler

Overrides:

endPrefixMapping in class DefaultContentHandler

Parameters:

prefix - passed through

Throws:

org.xml.sax.SAXException - if an error occurs

endDocument

public void endDocument()
                 throws org.xml.sax.SAXException

Description copied from class: DefaultContentHandler

Delegated to DefaultContentHandler.handler.

Specified by:

endDocument in interface org.xml.sax.ContentHandler

Overrides:

endDocument in class DefaultContentHandler

Throws:

org.xml.sax.SAXException - if an error occurs