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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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package javax.xml.transform;

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

/**

 * <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.

     */

    protected TransformerFactory() { }

    /**

     * 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 {@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 {@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 {@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 {@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.

     *

     * @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 {@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.

     *

     * @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.

     *

     * @return The URIResolver that was set with setURIResolver.

     */

    public abstract URIResolver getURIResolver();

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

        /**

         * <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.

     *

         * <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 {@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 {@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 {@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.

     *

     * @return The current error handler, which should never be null.

     */

    public abstract ErrorListener getErrorListener();

}