javax.xml.transform

Class TransformerFactory

java.lang.Object

javax.xml.transform.TransformerFactory

Direct Known Subclasses:

SAXTransformerFactory

public abstract class TransformerFactory
extends Object

A TransformerFactory instance can be used to create Transformer and Templates objects.

The system property that determines which Factory implementation to create is named "javax.xml.transform.TransformerFactory". This property names a concrete subclass of the TransformerFactory abstract class. If the property is not defined, a platform default is be used.

Since:

1.5

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	TransformerFactory() Default constructor is protected on purpose.

Method Summary

Methods

Modifier and Type	Method and Description
abstract Source	getAssociatedStylesheet(Source source, String media, String title, String charset) Get the stylesheet specification(s) associated with the XML Source document via the xml-stylesheet processing instruction that match the given criteria.
abstract Object	getAttribute(String name) Allows the user to retrieve specific attributes on the underlying implementation.
abstract ErrorListener	getErrorListener() Get the error event handler for the TransformerFactory.
abstract boolean	getFeature(String name) Look up the value of a feature.
abstract URIResolver	getURIResolver() Get the object that is used by default during the transformation to resolve URIs used in document(), xsl:import, or xsl:include.
static TransformerFactory	newInstance() Obtain a new instance of a TransformerFactory.
static TransformerFactory	newInstance(String factoryClassName, ClassLoader classLoader) Obtain a new instance of a TransformerFactory from factory class name.
abstract Templates	newTemplates(Source source) Process the Source into a Templates object, which is a a compiled representation of the source.
abstract Transformer	newTransformer() Create a new Transformer that performs a copy of the Source to the Result.
abstract Transformer	newTransformer(Source source) Process the Source into a Transformer Object.
abstract void	setAttribute(String name, Object value) Allows the user to set specific attributes on the underlying implementation.
abstract void	setErrorListener(ErrorListener listener) Set the error event listener for the TransformerFactory, which is used for the processing of transformation instructions, and not for the transformation itself.
abstract void	setFeature(String name, boolean value) Set a feature for this TransformerFactory and Transformers or Templates created by this factory.
abstract void	setURIResolver(URIResolver resolver) Set an object that is used by default during the transformation to resolve URIs used in document(), xsl:import, or xsl:include.

Methods inherited from class java.lang.Object

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

Constructor Detail

TransformerFactory

protected TransformerFactory()

Default constructor is protected on purpose.

Method Detail

newInstance

public static TransformerFactory newInstance()
                                      throws TransformerFactoryConfigurationError

Obtain a new instance of a TransformerFactory. This static method creates a new factory instance This method uses the following ordered lookup procedure to determine the TransformerFactory implementation class to load:

• Use the javax.xml.transform.TransformerFactory system property.
• Use the properties file "lib/jaxp.properties" in the JRE directory. This configuration file is in standard java.util.Properties format and contains the fully qualified name of the implementation class with the key being the system property defined above. The jaxp.properties file is read only once by the JAXP implementation and it's values are then cached for future use. If the file does not exist when the first attempt is made to read from it, no further attempts are made to check for its existence. It is not possible to change the value of any property in jaxp.properties after it has been read for the first time.
• Use the Services API (as detailed in the JAR specification), if available, to determine the classname. The Services API will look for a classname in the file META-INF/services/javax.xml.transform.TransformerFactory in jars available to the runtime.
• Platform default TransformerFactory instance.

Once an application has obtained a reference to a TransformerFactory it can use the factory to configure and obtain transformer instances.

Returns:

new TransformerFactory instance, never null.

Throws:

TransformerFactoryConfigurationError - Thrown if the implementation is not available or cannot be instantiated.

newInstance

public static TransformerFactory newInstance(String factoryClassName,
                             ClassLoader classLoader)
                                      throws TransformerFactoryConfigurationError

Obtain a new instance of a TransformerFactory from factory class name. This function is useful when there are multiple providers in the classpath. It gives more control to the application as it can specify which provider should be loaded.

Once an application has obtained a reference to a TransformerFactory it can use the factory to configure and obtain transformer instances.

Tip for Trouble-shooting

Setting the jaxp.debug system property will cause this method to print a lot of debug messages to System.err about what it is doing and where it is looking at.

If you have problems try:

 java -Djaxp.debug=1 YourProgram ....
 

Parameters:

factoryClassName - fully qualified factory class name that provides implementation of javax.xml.transform.TransformerFactory.

classLoader - ClassLoader used to load the factory class. If null current Thread's context classLoader is used to load the factory class.

Returns:

new TransformerFactory instance, never null.

Throws:

TransformerFactoryConfigurationError - if factoryClassName is null, or the factory class cannot be loaded, instantiated.

Since:

1.6

See Also:

newInstance()

newTransformer

public abstract Transformer newTransformer(Source source)
                                    throws TransformerConfigurationException

Process the Source into a Transformer Object. The Source is an XSLT document that conforms to XSL Transformations (XSLT) Version 1.0. Care must be taken not to use this Transformer in multiple Threads running concurrently. Different TransformerFactories can be used concurrently by different Threads.

Parameters:

source - Source of XSLT document used to create Transformer. Examples of XML Sources include DOMSource, SAXSource, and StreamSource.

Returns:

A Transformer object that may be used to perform a transformation in a single Thread, never null.

Throws:

TransformerConfigurationException - Thrown if there are errors when parsing the Source or it is not possible to create a Transformer instance.

See Also:

XSL Transformations (XSLT) Version 1.0

newTransformer

public abstract Transformer newTransformer()
                                    throws TransformerConfigurationException

Create a new Transformer that performs a copy of the Source to the Result. i.e. the "identity transform".

Returns:

A Transformer object that may be used to perform a transformation in a single thread, never null.

Throws:

TransformerConfigurationException - When it is not possible to create a Transformer instance.

newTemplates

public abstract Templates newTemplates(Source source)
                                throws TransformerConfigurationException

Process the Source into a Templates object, which is a a compiled representation of the source. This Templates object may then be used concurrently across multiple threads. Creating a Templates object allows the TransformerFactory to do detailed performance optimization of transformation instructions, without penalizing runtime transformation.

Parameters:

source - An object that holds a URL, input stream, etc.

Returns:

A Templates object capable of being used for transformation purposes, never null.

Throws:

TransformerConfigurationException - When parsing to construct the Templates object fails.

getAssociatedStylesheet

public abstract Source getAssociatedStylesheet(Source source,
                             String media,
                             String title,
                             String charset)
                                        throws TransformerConfigurationException

Get the stylesheet specification(s) associated with the XML Source document via the xml-stylesheet processing instruction that match the given criteria. Note that it is possible to return several stylesheets, in which case they are applied as if they were a list of imports or cascades in a single stylesheet.

Parameters:

source - The XML source document.

media - The media attribute to be matched. May be null, in which case the prefered templates will be used (i.e. alternate = no).

title - The value of the title attribute to match. May be null.

charset - The value of the charset attribute to match. May be null.

Returns:

A Source Object suitable for passing to the TransformerFactory.

Throws:

TransformerConfigurationException - An Exception is thrown if an error occurings during parsing of the source.

See Also:

Associating Style Sheets with XML documents Version 1.0

setURIResolver

public abstract void setURIResolver(URIResolver resolver)

Set an object that is used by default during the transformation to resolve URIs used in document(), xsl:import, or xsl:include.

Parameters:

resolver - An object that implements the URIResolver interface, or null.

getURIResolver

public abstract URIResolver getURIResolver()

Get the object that is used by default during the transformation to resolve URIs used in document(), xsl:import, or xsl:include.

Returns:

The URIResolver that was set with setURIResolver.

setFeature

public abstract void setFeature(String name,
              boolean value)
                         throws TransformerConfigurationException

Set a feature for this TransformerFactory and Transformers or Templates created by this factory.

Feature names are fully qualified URIs. Implementations may define their own features. An TransformerConfigurationException is thrown if this TransformerFactory or the Transformers or Templates it creates cannot support the feature. It is possible for an TransformerFactory to expose a feature value but be unable to change its state.

All implementations are required to support the XMLConstants.FEATURE_SECURE_PROCESSING feature. When the feature is:

• true: the implementation will limit XML processing to conform to implementation limits and behave in a secure fashion as defined by the implementation. Examples include resolving user defined style sheets and functions. If XML processing is limited for security reasons, it will be reported via a call to the registered ErrorListener.fatalError(TransformerException exception). See setErrorListener(ErrorListener listener).
• false: the implementation will processing XML according to the XML specifications without regard to possible implementation limits.

Parameters:

name - Feature name.

value - Is feature state true or false.

Throws:

TransformerConfigurationException - if this TransformerFactory or the Transformers or Templates it creates cannot support this feature.

NullPointerException - If the name parameter is null.

getFeature

public abstract boolean getFeature(String name)

Look up the value of a feature.

Feature names are fully qualified URIs. Implementations may define their own features. false is returned if this TransformerFactory or the Transformers or Templates it creates cannot support the feature. It is possible for an TransformerFactory to expose a feature value but be unable to change its state.

Parameters:

name - Feature name.

Returns:

The current state of the feature, true or false.

Throws:

NullPointerException - If the name parameter is null.

setAttribute

public abstract void setAttribute(String name,
                Object value)

Allows the user to set specific attributes on the underlying implementation. An attribute in this context is defined to be an option that the implementation provides. An IllegalArgumentException is thrown if the underlying implementation doesn't recognize the attribute.

All implementations that implement JAXP 1.5 or newer are required to support the XMLConstants.ACCESS_EXTERNAL_DTD and XMLConstants.ACCESS_EXTERNAL_STYLESHEET properties.

• Access to external DTDs in the source file is restricted to the protocols specified by the XMLConstants.ACCESS_EXTERNAL_DTD property. If access is denied during transformation due to the restriction of this property, TransformerException will be thrown by Transformer.transform(Source, Result).

  Access to external DTDs in the stylesheet is restricted to the protocols specified by the XMLConstants.ACCESS_EXTERNAL_DTD property. If access is denied during the creation of a new transformer due to the restriction of this property, TransformerConfigurationException will be thrown by the newTransformer(Source) method.

  Access to external reference set by the stylesheet processing instruction, Import and Include element is restricted to the protocols specified by the XMLConstants.ACCESS_EXTERNAL_STYLESHEET property. If access is denied during the creation of a new transformer due to the restriction of this property, TransformerConfigurationException will be thrown by the newTransformer(Source) method.

  Access to external document through XSLT document function is restricted to the protocols specified by the property. If access is denied during the transformation due to the restriction of this property, TransformerException will be thrown by the Transformer.transform(Source, Result) method.

Parameters:

name - The name of the attribute.

value - The value of the attribute.

Throws:

IllegalArgumentException - When implementation does not recognize the attribute.

getAttribute

public abstract Object getAttribute(String name)

Allows the user to retrieve specific attributes on the underlying implementation. An IllegalArgumentException is thrown if the underlying implementation doesn't recognize the attribute.

Parameters:

name - The name of the attribute.

Returns:

value The value of the attribute.

Throws:

IllegalArgumentException - When implementation does not recognize the attribute.

setErrorListener

public abstract void setErrorListener(ErrorListener listener)

Set the error event listener for the TransformerFactory, which is used for the processing of transformation instructions, and not for the transformation itself. An IllegalArgumentException is thrown if the ErrorListener listener is null.

Parameters:

listener - The new error listener.

Throws:

IllegalArgumentException - When listener is null

getErrorListener

public abstract ErrorListener getErrorListener()

Get the error event handler for the TransformerFactory.

Returns:

The current error handler, which should never be null.