org.jdom.input
Class SAXBuilder

java.lang.Object
  org.jdom.input.SAXBuilder

public class SAXBuilder
extends java.lang.Object

Builds a JDOM document from files, streams, readers, URLs, or a SAX InputSource instance using a SAX parser. The builder uses a third-party SAX parser (chosen by JAXP by default, or you can choose manually) to handle the parsing duties and simply listens to the SAX events to construct a document. Details which SAX does not provide, such as whitespace outside the root element, are not represented in the JDOM document. Information about SAX can be found at http://www.saxproject.org.

Known issues: Relative paths for a DocType or EntityRef may be converted by the SAX parser into absolute paths.

Version:

$Revision: 1.1 $, $Date: 2012/04/08 22:48:00 $

Author:

Jason Hunter, Brett McLaughlin, Dan Schaffer, Philip Nelson, Alex Rosen

Constructor Summary

SAXBuilder()
Creates a new SAXBuilder which will attempt to first locate a parser via JAXP, then will try to use a set of default SAX Drivers.

SAXBuilder(boolean validate)
Creates a new SAXBuilder which will attempt to first locate a parser via JAXP, then will try to use a set of default SAX Drivers.

SAXBuilder(java.lang.String saxDriverClass)
Creates a new SAXBuilder using the specified SAX parser.

SAXBuilder(java.lang.String saxDriverClass, boolean validate)
Creates a new SAXBuilder using the specified SAX parser.

Method Summary

Document	build(java.io.File file) This builds a document from the supplied filename.
Document	build(org.xml.sax.InputSource in) This builds a document from the supplied input source.
Document	build(java.io.InputStream in) This builds a document from the supplied input stream.
Document	build(java.io.InputStream in, java.lang.String systemId) This builds a document from the supplied input stream.
Document	build(java.io.Reader characterStream) This builds a document from the supplied Reader.
Document	build(java.io.Reader characterStream, java.lang.String systemId) This builds a document from the supplied Reader.
Document	build(java.lang.String systemId) This builds a document from the supplied URI.
Document	build(java.net.URL url) This builds a document from the supplied URL.
protected void	configureContentHandler(SAXHandler contentHandler) This configures the SAXHandler that will be used to build the Document.
protected void	configureParser(org.xml.sax.XMLReader parser, SAXHandler contentHandler) This configures the XMLReader to be used for reading the XML document.
protected SAXHandler	createContentHandler() This creates the SAXHandler that will be used to build the Document.
protected org.xml.sax.XMLReader	createParser() This creates the XMLReader to be used for reading the XML document.
java.lang.String	getDriverClass() Returns the driver class assigned in the constructor, or null if none.
org.xml.sax.DTDHandler	getDTDHandler() Returns the DTDHandler assigned, or null if none.
org.xml.sax.EntityResolver	getEntityResolver() Returns the EntityResolver assigned, or null if none.
org.xml.sax.ErrorHandler	getErrorHandler() Returns the ErrorHandler assigned, or null if none.
boolean	getExpandEntities() Returns whether or not entities are being expanded into normal text content.
JDOMFactory	getFactory() Returns the current JDOMFactory in use.
boolean	getIgnoringBoundaryWhitespace() Returns whether or not the parser will elminate element content containing only whitespace.
boolean	getIgnoringElementContentWhitespace() Returns whether element content whitespace is to be ignored during the build.
boolean	getReuseParser() Returns whether the contained SAX parser instance is reused across multiple parses.
boolean	getValidation() Returns whether validation is to be performed during the build.
org.xml.sax.XMLFilter	getXMLFilter() Returns the XMLFilter used during parsing, or null if none.
void	setDTDHandler(org.xml.sax.DTDHandler dtdHandler) This sets custom DTDHandler for the Builder.
void	setEntityResolver(org.xml.sax.EntityResolver entityResolver) This sets custom EntityResolver for the Builder.
void	setErrorHandler(org.xml.sax.ErrorHandler errorHandler) This sets custom ErrorHandler for the Builder.
void	setExpandEntities(boolean expand) This sets whether or not to expand entities for the builder.
void	setFactory(JDOMFactory factory) This sets a custom JDOMFactory for the builder.
void	setFastReconfigure(boolean fastReconfigure) Specifies whether this builder will do fast reconfiguration of the underlying SAX parser when reuseParser is true.
void	setFeature(java.lang.String name, boolean value) This sets a feature on the SAX parser.
void	setIgnoringBoundaryWhitespace(boolean ignoringBoundaryWhite) Specifies whether or not the parser should elminate boundary whitespace, a term that indicates whitespace-only text between element tags.
void	setIgnoringElementContentWhitespace(boolean ignoringWhite) Specifies whether or not the parser should elminate whitespace in element content (sometimes known as "ignorable whitespace") when building the document.
void	setProperty(java.lang.String name, java.lang.Object value) This sets a property on the SAX parser.
void	setReuseParser(boolean reuseParser) Specifies whether this builder shall reuse the same SAX parser when performing subsequent parses or allocate a new parser for each parse.
void	setValidation(boolean validate) This sets validation for the builder.
void	setXMLFilter(org.xml.sax.XMLFilter xmlFilter) This sets a custom XMLFilter for the builder.

Methods inherited from class java.lang.Object

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

Constructor Detail

SAXBuilder

public SAXBuilder()

Creates a new SAXBuilder which will attempt to first locate a parser via JAXP, then will try to use a set of default SAX Drivers. The underlying parser will not validate.

SAXBuilder

public SAXBuilder(boolean validate)

Creates a new SAXBuilder which will attempt to first locate a parser via JAXP, then will try to use a set of default SAX Drivers. The underlying parser will validate or not according to the given parameter.

Parameters:

validate - boolean indicating if validation should occur.

SAXBuilder

public SAXBuilder(java.lang.String saxDriverClass)

Creates a new SAXBuilder using the specified SAX parser. The underlying parser will not validate.

Parameters:

saxDriverClass - String name of SAX Driver to use for parsing.

SAXBuilder

public SAXBuilder(java.lang.String saxDriverClass,
                  boolean validate)

Creates a new SAXBuilder using the specified SAX parser. The underlying parser will validate or not according to the given parameter.

Parameters:

saxDriverClass - String name of SAX Driver to use for parsing.

validate - boolean indicating if validation should occur.

Method Detail

getDriverClass

public java.lang.String getDriverClass()

Returns the driver class assigned in the constructor, or null if none.

Returns:

the driver class assigned in the constructor

getFactory

public JDOMFactory getFactory()

Returns the current JDOMFactory in use.

Returns:

the factory in use

setFactory

public void setFactory(JDOMFactory factory)

This sets a custom JDOMFactory for the builder. Use this to build the tree with your own subclasses of the JDOM classes.

Parameters:

factory - JDOMFactory to use

getValidation

public boolean getValidation()

Returns whether validation is to be performed during the build.

Returns:

whether validation is to be performed during the build

setValidation

public void setValidation(boolean validate)

This sets validation for the builder.

Parameters:

validate - boolean indicating whether validation should occur.

getErrorHandler

public org.xml.sax.ErrorHandler getErrorHandler()

Returns the ErrorHandler assigned, or null if none.

Returns:

the ErrorHandler assigned, or null if none

setErrorHandler

public void setErrorHandler(org.xml.sax.ErrorHandler errorHandler)

This sets custom ErrorHandler for the Builder.

Parameters:

errorHandler - ErrorHandler

getEntityResolver

public org.xml.sax.EntityResolver getEntityResolver()

Returns the EntityResolver assigned, or null if none.

Returns:

the EntityResolver assigned

setEntityResolver

public void setEntityResolver(org.xml.sax.EntityResolver entityResolver)

This sets custom EntityResolver for the Builder.

Parameters:

entityResolver - EntityResolver

getDTDHandler

public org.xml.sax.DTDHandler getDTDHandler()

Returns the DTDHandler assigned, or null if none.

Returns:

the DTDHandler assigned

setDTDHandler

public void setDTDHandler(org.xml.sax.DTDHandler dtdHandler)

This sets custom DTDHandler for the Builder.

Parameters:

dtdHandler - DTDHandler

getXMLFilter

public org.xml.sax.XMLFilter getXMLFilter()

Returns the XMLFilter used during parsing, or null if none.

Returns:

the XMLFilter used during parsing

setXMLFilter

public void setXMLFilter(org.xml.sax.XMLFilter xmlFilter)

This sets a custom XMLFilter for the builder.

Parameters:

xmlFilter - the filter to use

getIgnoringElementContentWhitespace

public boolean getIgnoringElementContentWhitespace()

Returns whether element content whitespace is to be ignored during the build.

Returns:

whether element content whitespace is to be ignored during the build

setIgnoringElementContentWhitespace

public void setIgnoringElementContentWhitespace(boolean ignoringWhite)

Specifies whether or not the parser should elminate whitespace in element content (sometimes known as "ignorable whitespace") when building the document. Only whitespace which is contained within element content that has an element only content model will be eliminated (see XML Rec 3.2.1). For this setting to take effect requires that validation be turned on. The default value of this setting is false.

Parameters:

ignoringWhite - Whether to ignore ignorable whitespace

getIgnoringBoundaryWhitespace

public boolean getIgnoringBoundaryWhitespace()

Returns whether or not the parser will elminate element content containing only whitespace.

Returns:

boolean - whether only whitespace content will be ignored during build.

See Also:

setIgnoringBoundaryWhitespace(boolean)

setIgnoringBoundaryWhitespace

public void setIgnoringBoundaryWhitespace(boolean ignoringBoundaryWhite)

Specifies whether or not the parser should elminate boundary whitespace, a term that indicates whitespace-only text between element tags. This feature is a lot like setIgnoringElementContentWhitespace(boolean) but this feature is more aggressive and doesn't require validation be turned on. The setIgnoringElementContentWhitespace(boolean) call impacts the SAX parse process while this method impacts the JDOM build process, so it can be beneficial to turn both on for efficiency. For implementation efficiency, this method actually removes all whitespace-only text() nodes. That can, in some cases (like beteween an element tag and a comment), include whitespace that isn't just boundary whitespace. The default is false.

Parameters:

ignoringBoundaryWhite - Whether to ignore whitespace-only text noes

getReuseParser

public boolean getReuseParser()

Returns whether the contained SAX parser instance is reused across multiple parses. The default is true.

Returns:

whether the contained SAX parser instance is reused across multiple parses

setReuseParser

public void setReuseParser(boolean reuseParser)

Specifies whether this builder shall reuse the same SAX parser when performing subsequent parses or allocate a new parser for each parse. The default value of this setting is true (parser reuse).

Note: As SAX parser instances are not thread safe, the parser reuse feature should not be used with SAXBuilder instances shared among threads.

Parameters:

reuseParser - Whether to reuse the SAX parser.

setFastReconfigure

public void setFastReconfigure(boolean fastReconfigure)

Specifies whether this builder will do fast reconfiguration of the underlying SAX parser when reuseParser is true. This improves performance in cases where SAXBuilders are reused and lots of small documents are frequently parsed. This avoids attempting to set features on the SAX parser each time build() is called which result in SaxNotRecognizedExceptions. This should ONLY be set for builders where this specific case is an issue. The default value of this setting is false (no fast reconfiguration). If reuseParser is false, calling this has no effect.

Parameters:

fastReconfigure - Whether to do a fast reconfiguration of the parser

setFeature

public void setFeature(java.lang.String name,
                       boolean value)

This sets a feature on the SAX parser. See the SAX documentation for . more information.

NOTE: SAXBuilder requires that some particular features of the SAX parser be set up in certain ways for it to work properly. The list of such features may change in the future. Therefore, the use of this method may cause parsing to break, and even if it doesn't break anything today it might break parsing in a future JDOM version, because what JDOM parsers require may change over time. Use with caution.

Parameters:

name - The feature name, which is a fully-qualified URI.

value - The requested state of the feature (true or false).

setProperty

public void setProperty(java.lang.String name,
                        java.lang.Object value)

This sets a property on the SAX parser. See the SAX documentation for more information.

NOTE: SAXBuilder requires that some particular properties of the SAX parser be set up in certain ways for it to work properly. The list of such properties may change in the future. Therefore, the use of this method may cause parsing to break, and even if it doesn't break anything today it might break parsing in a future JDOM version, because what JDOM parsers require may change over time. Use with caution.

Parameters:

name - The property name, which is a fully-qualified URI.

value - The requested value for the property.

build

public Document build(org.xml.sax.InputSource in)
               throws JDOMException,
                      java.io.IOException

This builds a document from the supplied input source.

Parameters:

in - InputSource to read from

Returns:

Document resultant Document object

Throws:

JDOMException - when errors occur in parsing

java.io.IOException - when an I/O error prevents a document from being fully parsed

createContentHandler

protected SAXHandler createContentHandler()

This creates the SAXHandler that will be used to build the Document.

Returns:

SAXHandler - resultant SAXHandler object.

configureContentHandler

protected void configureContentHandler(SAXHandler contentHandler)

This configures the SAXHandler that will be used to build the Document.

The default implementation simply passes through some configuration settings that were set on the SAXBuilder: setExpandEntities() and setIgnoringElementContentWhitespace().

Parameters:

contentHandler - The SAXHandler to configure

createParser

protected org.xml.sax.XMLReader createParser()
                                      throws JDOMException

This creates the XMLReader to be used for reading the XML document.

The default behavior is to (1) use the saxDriverClass, if it has been set, (2) try to obtain a parser from JAXP, if it is available, and (3) if all else fails, use a hard-coded default parser (currently the Xerces parser). Subclasses may override this method to determine the parser to use in a different way.

Returns:

XMLReader - resultant XMLReader object.

Throws:

JDOMException

configureParser

protected void configureParser(org.xml.sax.XMLReader parser,
                               SAXHandler contentHandler)
                        throws JDOMException

This configures the XMLReader to be used for reading the XML document.

The default implementation sets various options on the given XMLReader, such as validation, DTD resolution, entity handlers, etc., according to the options that were set (e.g. via setEntityResolver) and set various SAX properties and features that are required for JDOM internals. These features may change in future releases, so change this behavior at your own risk.

Parameters:

parser -

contentHandler -

Throws:

JDOMException

build

public Document build(java.io.InputStream in)
               throws JDOMException,
                      java.io.IOException

This builds a document from the supplied input stream.

Parameters:

in - InputStream to read from

Returns:

Document resultant Document object

Throws:

JDOMException - when errors occur in parsing

java.io.IOException - when an I/O error prevents a document from being fully parsed.

build

public Document build(java.io.File file)
               throws JDOMException,
                      java.io.IOException

This builds a document from the supplied filename.

Parameters:

file - File to read from

Returns:

Document resultant Document object

Throws:

JDOMException - when errors occur in parsing

java.io.IOException - when an I/O error prevents a document from being fully parsed

build

public Document build(java.net.URL url)
               throws JDOMException,
                      java.io.IOException

This builds a document from the supplied URL.

Parameters:

url - URL to read from.

Returns:

Document - resultant Document object.

Throws:

JDOMException - when errors occur in parsing

java.io.IOException - when an I/O error prevents a document from being fully parsed.

build

public Document build(java.io.InputStream in,
                      java.lang.String systemId)
               throws JDOMException,
                      java.io.IOException

This builds a document from the supplied input stream.

Parameters:

in - InputStream to read from.

systemId - base for resolving relative URIs

Returns:

Document resultant Document object

Throws:

JDOMException - when errors occur in parsing

java.io.IOException - when an I/O error prevents a document from being fully parsed

build

public Document build(java.io.Reader characterStream)
               throws JDOMException,
                      java.io.IOException

This builds a document from the supplied Reader. It's the programmer's responsibility to make sure the reader matches the encoding of the file. It's often easier and safer to use an InputStream rather than a Reader, and to let the parser auto-detect the encoding from the XML declaration.

Parameters:

characterStream - Reader to read from

Returns:

Document resultant Document object

Throws:

JDOMException - when errors occur in parsing

java.io.IOException - when an I/O error prevents a document from being fully parsed

build

public Document build(java.io.Reader characterStream,
                      java.lang.String systemId)
               throws JDOMException,
                      java.io.IOException

This builds a document from the supplied Reader. It's the programmer's responsibility to make sure the reader matches the encoding of the file. It's often easier and safer to use an InputStream rather than a Reader, and to let the parser auto-detect the encoding from the XML declaration.

Parameters:

characterStream - Reader to read from.

systemId - base for resolving relative URIs

Returns:

Document resultant Document object

Throws:

JDOMException - when errors occur in parsing

java.io.IOException - when an I/O error prevents a document from being fully parsed

build

public Document build(java.lang.String systemId)
               throws JDOMException,
                      java.io.IOException

This builds a document from the supplied URI.

Parameters:

systemId - URI for the input

Returns:

Document resultant Document object

Throws:

JDOMException - when errors occur in parsing

java.io.IOException - when an I/O error prevents a document from being fully parsed

getExpandEntities

public boolean getExpandEntities()

Returns whether or not entities are being expanded into normal text content.

Returns:

whether entities are being expanded

setExpandEntities

public void setExpandEntities(boolean expand)

This sets whether or not to expand entities for the builder. A true means to expand entities as normal content. A false means to leave entities unexpanded as EntityRef objects. The default is true.

When this setting is false, the internal DTD subset is retained; when this setting is true, the internal DTD subset is not retained.

Note that Xerces (at least up to 1.4.4) has a bug where entities in attribute values will be misreported if this flag is turned off, resulting in entities to appear within element content. When turning entity expansion off either avoid entities in attribute values, or use another parser like Crimson. http://nagoya.apache.org/bugzilla/show_bug.cgi?id=6111

Parameters:

expand - boolean indicating whether entity expansion should occur.