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package javax.xml.transform;

import com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl;

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. 
Author:
Jeff Suttor, Neeraj Bajaj
Since:
1.5/**
 * <p>A TransformerFactory instance can be used to create
 * {@link javax.xml.transform.Transformer} and
 * {@link javax.xml.transform.Templates} objects.
 *
 * <p>The system property that determines which Factory implementation
 * to create is named {@code "javax.xml.transform.TransformerFactory"}.
 * This property names a concrete subclass of the
 * {@code TransformerFactory} abstract class. If the property is not
 * defined, a platform default is be used.
 *
 * @author Jeff Suttor
 * @author Neeraj Bajaj
 *
 * @since 1.5
 */
public abstract class TransformerFactory {

    
Default constructor is protected on purpose.
/**
     * Default constructor is protected on purpose.
     */
    protected TransformerFactory() { }



    
Creates a new instance of the TransformerFactory builtin system-default implementation. 
Returns:
A new instance of the TransformerFactory builtin system-default implementation.
Since:
9/**
     * Creates a new instance of the {@code TransformerFactory} builtin
     * system-default implementation.
     *
     * @return A new instance of the {@code TransformerFactory} builtin
     *         system-default implementation.
     *
     * @since 9
     */
    public static TransformerFactory newDefaultInstance() {
        return new TransformerFactoryImpl();
    }

    
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 configuration file "jaxp.properties". The file is in standard Properties format and typically located in the conf directory of the Java installation. It 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 its 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 service-provider loading facility, defined by the ServiceLoader class, to attempt to locate and load an implementation of the service using the default loading mechanism: the service-provider loading facility will use the current thread's context class loader to attempt to load the service. If the context class loader is null, the system class loader will be used. 

 Otherwise, the system-default implementation is returned. 

 Once an application has obtained a reference to a TransformerFactory it can use the factory to configure and obtain transformer instances. 
Throws:
TransformerFactoryConfigurationError – Thrown in case of service configuration error or if the implementation is not available or cannot be instantiated.
Returns:
new TransformerFactory instance, never null./**
     * Obtain a new instance of a {@code TransformerFactory}.
     * This static method creates a new factory instance.
     * <p>
     * This method uses the following ordered lookup procedure to determine
     * the {@code TransformerFactory} implementation class to load:
     * <ul>
     * <li>
     * Use the {@code javax.xml.transform.TransformerFactory} system
     * property.
     * </li>
     * <li>
     * <p>
     * Use the configuration file "jaxp.properties". The file is in standard
     * {@link java.util.Properties} format and typically located in the
     * {@code conf} directory of the Java installation. It contains the fully qualified
     * name of the implementation class with the key being the system property
     * defined above.
     * <p>
     * The jaxp.properties file is read only once by the JAXP implementation
     * and its 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.
     * </li>
     * <li>
     * <p>
     * Use the service-provider loading facility, defined by the
     *   {@link java.util.ServiceLoader} class, to attempt to locate and load an
     *   implementation of the service using the {@linkplain
     *   java.util.ServiceLoader#load(java.lang.Class) default loading mechanism}:
     *   the service-provider loading facility will use the {@linkplain
     *   java.lang.Thread#getContextClassLoader() current thread's context class loader}
     *   to attempt to load the service. If the context class
     *   loader is null, the {@linkplain
     *   ClassLoader#getSystemClassLoader() system class loader} will be used.
     * </li>
     * <li>
     * <p>
     *   Otherwise, the {@linkplain #newDefaultInstance() system-default}
     *   implementation is returned.
     * </li>
     * </ul>
     *
     * <p>
     * Once an application has obtained a reference to a
     * {@code TransformerFactory} it can use the factory to configure
     * and obtain transformer instances.
     *
     * @return new TransformerFactory instance, never null.
     *
     * @throws TransformerFactoryConfigurationError Thrown in case of {@linkplain
     * java.util.ServiceConfigurationError service configuration error} or if
     * the implementation is not available or cannot be instantiated.
     */
    public static TransformerFactory newInstance()
        throws TransformerFactoryConfigurationError {

        return FactoryFinder.find(
            /* The default property name according to the JAXP spec */
            TransformerFactory.class,
            /* The fallback implementation class name, XSLTC */
            "com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl");
    }

    
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 ....

Params:
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.
Throws:
TransformerFactoryConfigurationError –  if factoryClassName is null, or the factory class cannot be loaded, instantiated.
See Also:
newInstance()
Returns:
new TransformerFactory instance, never null.
Since:
1.6/**
     * Obtain a new instance of a {@code 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.
     *
     * <p>Once an application has obtained a reference to a
     * {@code TransformerFactory} it can use the factory to configure
     * and obtain transformer instances.
     *
     * <h2>Tip for Trouble-shooting</h2>
     * <p>Setting the {@code jaxp.debug} system property will cause
     * this method to print a lot of debug messages
     * to {@code System.err} about what it is doing and where it is looking at.
     *
     * <p> If you have problems try:
     * <pre>
     * java -Djaxp.debug=1 YourProgram ....
     * </pre>
     *
     * @param factoryClassName fully qualified factory class name that provides implementation of {@code javax.xml.transform.TransformerFactory}.
     *
     * @param classLoader {@code ClassLoader} used to load the factory class. If {@code null}
     *                     current {@code Thread}'s context classLoader is used to load the factory class.
     *
     * @return new TransformerFactory instance, never null.
     *
     * @throws TransformerFactoryConfigurationError
     *                    if {@code factoryClassName} is {@code null}, or
     *                   the factory class cannot be loaded, instantiated.
     *
     * @see #newInstance()
     *
     * @since 1.6
     */
    public static TransformerFactory newInstance(String factoryClassName, ClassLoader classLoader)
        throws TransformerFactoryConfigurationError{

        //do not fallback if given classloader can't find the class, throw exception
        return  FactoryFinder.newInstance(TransformerFactory.class,
                    factoryClassName, classLoader, false);
    }
    
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. 
Params:
source – Source  of XSLT document used to create Transformer. Examples of XML Sources include DOMSource, SAXSource, and StreamSource.
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
Returns:
A Transformer object that may be used to perform a transformation in a single Thread, never null./**
     * Process the {@code Source} into a {@code Transformer}
     * {@code Object}.  The {@code Source} is an XSLT document that
     * conforms to <a href="http://www.w3.org/TR/xslt">
     * XSL Transformations (XSLT) Version 1.0</a>.  Care must
     * be taken not to use this {@code Transformer} in multiple
     * {@code Thread}s running concurrently.
     * Different {@code TransformerFactories} can be used concurrently by
     * different {@code Thread}s.
     *
     * @param source {@code Source } of XSLT document used to create
     *   {@code Transformer}.
     *   Examples of XML {@code Source}s include
     *   {@link javax.xml.transform.dom.DOMSource DOMSource},
     *   {@link javax.xml.transform.sax.SAXSource SAXSource}, and
     *   {@link javax.xml.transform.stream.StreamSource StreamSource}.
     *
     * @return A {@code Transformer} object that may be used to perform
     *   a transformation in a single {@code Thread}, never
     *   {@code null}.
     *
     * @throws TransformerConfigurationException Thrown if there are errors when
     *    parsing the {@code Source} or it is not possible to create a
     *   {@code Transformer} instance.
     *
     * @see <a href="http://www.w3.org/TR/xslt">
     *   XSL Transformations (XSLT) Version 1.0</a>
     */
    public abstract Transformer newTransformer(Source source)
        throws TransformerConfigurationException;

    
Create a new Transformer that performs a copy of the Source to the Result. i.e. the "identity transform".
Throws:
TransformerConfigurationException – When it is not possible to create a Transformer instance.
Returns:
A Transformer object that may be used to perform a transformation
in a single thread, never null./**
     * Create a new {@code Transformer} that performs a copy
     * of the {@code Source} to the {@code Result}.
     * i.e. the "<em>identity transform</em>".
     *
     * @return 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 {@code Transformer} instance.
     */
    public abstract Transformer newTransformer()
        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.
Params:
source – An object that holds a URL, input stream, etc.
Throws:
TransformerConfigurationException – When parsing to
  construct the Templates object fails.
Returns:
A Templates object capable of being used for transformation purposes, never null./**
     * 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.
     *
     * @param source An object that holds a URL, input stream, etc.
     *
     * @return A Templates object capable of being used for transformation
     *   purposes, never {@code null}.
     *
     * @throws TransformerConfigurationException When parsing to
     *   construct the Templates object fails.
     */
    public abstract Templates newTemplates(Source source)
        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.
Params:
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.
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
Returns:
A Source Object suitable for passing to the TransformerFactory./**
     * Get the stylesheet specification(s) associated with the
     * XML {@code Source} document via the
     * <a href="http://www.w3.org/TR/xml-stylesheet/">
     * xml-stylesheet processing instruction</a> 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.
     *
     * @param source The XML source document.
     * @param media The media attribute to be matched.  May be null, in which
     *      case the prefered templates will be used (i.e. alternate = no).
     * @param title The value of the title attribute to match.  May be null.
     * @param charset The value of the charset attribute to match.  May be null.
     *
     * @return A {@code Source} {@code Object} suitable for passing
     *   to the {@code TransformerFactory}.
     *
     * @throws TransformerConfigurationException An {@code Exception}
     *   is thrown if an error occurings during parsing of the
     *   {@code source}.
     *
     * @see <a href="http://www.w3.org/TR/xml-stylesheet/">
     *   Associating Style Sheets with XML documents Version 1.0</a>
     */
    public abstract Source getAssociatedStylesheet(
        Source source,
        String media,
        String title,
        String charset)
        throws TransformerConfigurationException;

    
Set an object that is used by default during the transformation
to resolve URIs used in document(), xsl:import, or xsl:include.
Params:
resolver – An object that implements the URIResolver interface,
or null./**
     * Set an object that is used by default during the transformation
     * to resolve URIs used in document(), xsl:import, or xsl:include.
     *
     * @param resolver An object that implements the URIResolver interface,
     * or null.
     */
    public abstract void setURIResolver(URIResolver resolver);

    
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./**
     * Get the object that is used by default during the transformation
     * to resolve URIs used in document(), xsl:import, or xsl:include.
     *
     * @return The URIResolver that was set with setURIResolver.
     */
    public abstract URIResolver getURIResolver();

    //======= CONFIGURATION METHODS =======

        
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. 

Params:
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./**
         * <p>Set a feature for this {@code TransformerFactory} and {@code Transformer}s
         * or {@code Template}s created by this factory.
         *
         * <p>
         * Feature names are fully qualified {@link java.net.URI}s.
         * Implementations may define their own features.
         * An {@link TransformerConfigurationException} is thrown if this {@code TransformerFactory} or the
         * {@code Transformer}s or {@code Template}s it creates cannot support the feature.
         * It is possible for an {@code TransformerFactory} to expose a feature value but be unable to change its state.
         *
         * <p>All implementations are required to support the {@link javax.xml.XMLConstants#FEATURE_SECURE_PROCESSING} feature.
         * When the feature is:
         * <ul>
         *   <li>
         *     {@code 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
         *     {@link ErrorListener#fatalError(TransformerException exception)}.
         *     See {@link  #setErrorListener(ErrorListener listener)}.
         *   </li>
         *   <li>
         *     {@code false}: the implementation will processing XML according to the XML specifications without
         *     regard to possible implementation limits.
         *   </li>
         * </ul>
         *
         * @param name Feature name.
         * @param value Is feature state {@code true} or {@code false}.
         *
         * @throws TransformerConfigurationException if this {@code TransformerFactory}
         *   or the {@code Transformer}s or {@code Template}s it creates cannot support this feature.
     * @throws NullPointerException If the {@code name} parameter is null.
         */
        public abstract void setFeature(String name, boolean value)
                throws TransformerConfigurationException;

    
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. 
Params:
name – Feature name.
Throws:
NullPointerException – If the name parameter is null.
Returns:
The current state of the feature, true or false./**
     * Look up the value of a feature.
     *
         * <p>
         * Feature names are fully qualified {@link java.net.URI}s.
         * Implementations may define their own features.
         * {@code false} is returned if this {@code TransformerFactory} or the
         * {@code Transformer}s or {@code Template}s it creates cannot support the feature.
         * It is possible for an {@code TransformerFactory} to expose a feature value but be unable to change its state.
         *
         * @param name Feature name.
         *
     * @return The current state of the feature, {@code true} or {@code false}.
     *
     * @throws NullPointerException If the {@code name} parameter is null.
     */
    public abstract boolean getFeature(String name);

    
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. 

Params:
name – The name of the attribute.
value – The value of the attribute.
Throws:
IllegalArgumentException – When implementation does not
  recognize the attribute./**
     * 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 {@code IllegalArgumentException} is thrown if the underlying
     * implementation doesn't recognize the attribute.
     * <p>
     * All implementations that implement JAXP 1.5 or newer are required to
     * support the {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_DTD}  and
     * {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_STYLESHEET} properties.
     *
     * <ul>
     *   <li>
     *      <p>
     *      Access to external DTDs in the source file is restricted to the protocols
     *      specified by the {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_DTD} property.
     *      If access is denied during transformation due to the restriction of this property,
     *      {@link javax.xml.transform.TransformerException} will be thrown by
     *      {@link javax.xml.transform.Transformer#transform(Source, Result)}.
     *
     *      <p>
     *      Access to external DTDs in the stylesheet is restricted to the protocols
     *      specified by the {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_DTD} property.
     *      If access is denied during the creation of a new transformer due to the
     *      restriction of this property,
     *      {@link javax.xml.transform.TransformerConfigurationException} will be thrown
     *      by the {@link #newTransformer(Source)} method.
     *
     *      <p>
     *      Access to external reference set by the stylesheet processing instruction,
     *      Import and Include element is restricted to the protocols specified by the
     *      {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_STYLESHEET} property.
     *      If access is denied during the creation of a new transformer due to the
     *      restriction of this property,
     *      {@link javax.xml.transform.TransformerConfigurationException} will be thrown
     *      by the {@link #newTransformer(Source)} method.
     *
     *      <p>
     *      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,
     *      {@link javax.xml.transform.TransformerException} will be thrown by the
     *      {@link javax.xml.transform.Transformer#transform(Source, Result)} method.
     *
     *   </li>
     * </ul>
     *
     * @param name The name of the attribute.
     * @param value The value of the attribute.
     *
     * @throws IllegalArgumentException When implementation does not
     *   recognize the attribute.
     */
    public abstract void setAttribute(String name, Object value);

    
Allows the user to retrieve specific attributes on the underlying implementation. An IllegalArgumentException is thrown if the underlying implementation doesn't recognize the attribute. 
Params:
name – The name of the attribute.
Throws:
IllegalArgumentException – When implementation does not
  recognize the attribute.
Returns:
value The value of the attribute./**
     * Allows the user to retrieve specific attributes on the underlying
     * implementation.
     * An {@code IllegalArgumentException} is thrown if the underlying
     * implementation doesn't recognize the attribute.
     *
     * @param name The name of the attribute.
     *
     * @return value The value of the attribute.
     *
     * @throws IllegalArgumentException When implementation does not
     *   recognize the attribute.
     */
    public abstract Object getAttribute(String name);

    
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. 
Params:
listener – The new error listener.
Throws:
IllegalArgumentException – When listener is null/**
     * Set the error event listener for the TransformerFactory, which
     * is used for the processing of transformation instructions,
     * and not for the transformation itself.
     * An {@code IllegalArgumentException} is thrown if the
     * {@code ErrorListener} listener is {@code null}.
     *
     * @param listener The new error listener.
     *
     * @throws IllegalArgumentException When {@code listener} is
     *   {@code null}
     */
    public abstract void setErrorListener(ErrorListener listener);

    
Get the error event handler for the TransformerFactory.
Returns:
The current error handler, which should never be null./**
     * Get the error event handler for the TransformerFactory.
     *
     * @return The current error handler, which should never be null.
     */
    public abstract ErrorListener getErrorListener();

}