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package javax.xml.parsers;

import com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl;

import javax.xml.validation.Schema;

import org.xml.sax.SAXException;

import org.xml.sax.SAXNotRecognizedException;

import org.xml.sax.SAXNotSupportedException;

/**

 * Defines a factory API that enables applications to configure and

 * obtain a SAX based parser to parse XML documents.

 *

 *

 * @since 1.4

 */

public abstract class SAXParserFactory {

    /**

     * Should Parsers be validating?

     */

    private boolean validating = false;

    /**

     * Should Parsers be namespace aware?

     */

    private boolean namespaceAware = false;

    /**

     * Protected constructor to force use of {@link #newInstance()}.

     */

    protected SAXParserFactory () {

    }

    /**

     * Creates a new instance of the {@code SAXParserFactory} builtin

     * system-default implementation.

     *

     * @return A new instance of the {@code SAXParserFactory} builtin

     *         system-default implementation.

     *

     * @since 9

     */

    public static SAXParserFactory newDefaultInstance() {

        return new SAXParserFactoryImpl();

    }

    /**

     * Obtain a new instance of a {@code SAXParserFactory}. This

     * static method creates a new factory instance

     * This method uses the following ordered lookup procedure to determine

     * the {@code SAXParserFactory} implementation class to

     * load:

     * <ul>

     * <li>

     * Use the {@code javax.xml.parsers.SAXParserFactory} 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 SAXParserFactory} it can use the factory to

     * configure and obtain parser 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 loading {@link SAXParser}s, try:

     * <pre>

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

     * </pre>

     *

     *

     * @return A new instance of a SAXParserFactory.

     *

     * @throws FactoryConfigurationError in case of {@linkplain

     * java.util.ServiceConfigurationError service configuration error} or if

     * the implementation is not available or cannot be instantiated.

     */

    public static SAXParserFactory newInstance() {

        return FactoryFinder.find(

                /* The default property name according to the JAXP spec */

                SAXParserFactory.class,

                /* The fallback implementation class name */

                "com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl");

    }

    /**

     * Obtain a new instance of a {@code SAXParserFactory} from 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 SAXParserFactory}

     * it can use the factory to configure and obtain parser 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.parsers.SAXParserFactory}.

     *

     * @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 instance of a {@code SAXParserFactory}

     *

     * @throws FactoryConfigurationError if {@code factoryClassName} is {@code null}, or

     *                                   the factory class cannot be loaded, instantiated.

     *

     * @see #newInstance()

     *

     * @since 1.6

     */

    public static SAXParserFactory newInstance(String factoryClassName, ClassLoader classLoader){

            //do not fallback if given classloader can't find the class, throw exception

            return FactoryFinder.newInstance(SAXParserFactory.class,

                    factoryClassName, classLoader, false);

    }

    /**

     * Creates a new instance of a SAXParser using the currently

     * configured factory parameters.

     *

     * @return A new instance of a SAXParser.

     *

     * @throws ParserConfigurationException if a parser cannot

     *   be created which satisfies the requested configuration.

     * @throws SAXException for SAX errors.

     */

    public abstract SAXParser newSAXParser()

        throws ParserConfigurationException, SAXException;

    /**

     * Specifies that the parser produced by this code will

     * provide support for XML namespaces. By default the value of this is set

     * to {@code false}.

     *

     * @param awareness true if the parser produced by this code will

     *                  provide support for XML namespaces; false otherwise.

     */

    public void setNamespaceAware(boolean awareness) {

        this.namespaceAware = awareness;

    }

    /**

     * Specifies that the parser produced by this code will

     * validate documents as they are parsed. By default the value of this is

     * set to {@code false}.

     *

     * <p>

     * Note that "the validation" here means

     * <a href="http://www.w3.org/TR/REC-xml#proc-types">a validating

     * parser</a> as defined in the XML recommendation.

     * In other words, it essentially just controls the DTD validation.

     * (except the legacy two properties defined in JAXP 1.2.)

     *

     * <p>

     * To use modern schema languages such as W3C XML Schema or

     * RELAX NG instead of DTD, you can configure your parser to be

     * a non-validating parser by leaving the {@link #setValidating(boolean)}

     * method {@code false}, then use the {@link #setSchema(Schema)}

     * method to associate a schema to a parser.

     *

     * @param validating true if the parser produced by this code will

     *                   validate documents as they are parsed; false otherwise.

     */

    public void setValidating(boolean validating) {

        this.validating = validating;

    }

    /**

     * Indicates whether or not the factory is configured to produce

     * parsers which are namespace aware.

     *

     * @return true if the factory is configured to produce

     *         parsers which are namespace aware; false otherwise.

     */

    public boolean isNamespaceAware() {

        return namespaceAware;

    }

    /**

     * Indicates whether or not the factory is configured to produce

     * parsers which validate the XML content during parse.

     *

     * @return true if the factory is configured to produce parsers which validate

     *         the XML content during parse; false otherwise.

     */

    public boolean isValidating() {

        return validating;

    }

    /**

     * Sets the particular feature in the underlying implementation of

     * org.xml.sax.XMLReader.

     * A list of the core features and properties can be found at

     * <a href="http://www.saxproject.org/">http://www.saxproject.org/</a>

     *

     * <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.

     *     Examples include entity expansion limits and XML Schema constructs that would consume large amounts of resources.

     *     If XML processing is limited for security reasons, it will be reported via a call to the registered

     *     {@link org.xml.sax.ErrorHandler#fatalError(SAXParseException exception)}.

     *     See {@link SAXParser} {@code parse} methods for handler specification.

     *   </li>

     *   <li>

     *     When the feature is {@code false}, the implementation will processing XML according to the XML specifications without

     *     regard to possible implementation limits.

     *   </li>

     * </ul>

     *

     * @param name The name of the feature to be set.

     * @param value The value of the feature to be set.

     *

     * @throws ParserConfigurationException if a parser cannot

     *     be created which satisfies the requested configuration.

     * @throws SAXNotRecognizedException When the underlying XMLReader does

     *            not recognize the property name.

     * @throws SAXNotSupportedException When the underlying XMLReader

     *            recognizes the property name but doesn't support the

     *            property.

     * @throws NullPointerException If the {@code name} parameter is null.

     *

     * @see org.xml.sax.XMLReader#setFeature

     */

    public abstract void setFeature(String name, boolean value)

        throws ParserConfigurationException, SAXNotRecognizedException,

                SAXNotSupportedException;

    /**

     *

     * Returns the particular property requested for in the underlying

     * implementation of org.xml.sax.XMLReader.

     *

     * @param name The name of the property to be retrieved.

     *

     * @return Value of the requested property.

     *

     * @throws ParserConfigurationException if a parser cannot be created which satisfies the requested configuration.

     * @throws SAXNotRecognizedException When the underlying XMLReader does not recognize the property name.

     * @throws SAXNotSupportedException When the underlying XMLReader recognizes the property name but doesn't support the property.

     *

     * @see org.xml.sax.XMLReader#getProperty

     */

    public abstract boolean getFeature(String name)

        throws ParserConfigurationException, SAXNotRecognizedException,

                SAXNotSupportedException;

    /**

     * Gets the {@link Schema} object specified through

     * the {@link #setSchema(Schema schema)} method.

     *

     *

     * @throws UnsupportedOperationException When implementation does not

     *   override this method

     *

     * @return

     *      the {@link Schema} object that was last set through

     *      the {@link #setSchema(Schema)} method, or null

     *      if the method was not invoked since a {@link SAXParserFactory}

     *      is created.

     *

     * @since 1.5

     */

    public Schema getSchema() {

        throw new UnsupportedOperationException(

            "This parser does not support specification \""

            + this.getClass().getPackage().getSpecificationTitle()

            + "\" version \""

            + this.getClass().getPackage().getSpecificationVersion()

            + "\""

            );

    }

    /**

     * Set the {@link Schema} to be used by parsers created

     * from this factory.

     *

     * <p>When a {@link Schema} is non-null, a parser will use a validator

     * created from it to validate documents before it passes information

     * down to the application.

     *

     * <p>When warnings/errors/fatal errors are found by the validator, the parser must

     * handle them as if those errors were found by the parser itself.

     * In other words, if the user-specified {@link org.xml.sax.ErrorHandler}

     * is set, it must receive those errors, and if not, they must be

     * treated according to the implementation specific

     * default error handling rules.

     *

     * <p>A validator may modify the SAX event stream (for example by

     * adding default values that were missing in documents), and a parser

     * is responsible to make sure that the application will receive

     * those modified event stream.

     *

     * <p>Initially, {@code null} is set as the {@link Schema}.

     *

     * <p>This processing will take effect even if

     * the {@link #isValidating()} method returns {@code false}.

     *

     * <p>It is an error to use

     * the {@code http://java.sun.com/xml/jaxp/properties/schemaSource}

     * property and/or the {@code http://java.sun.com/xml/jaxp/properties/schemaLanguage}

     * property in conjunction with a non-null {@link Schema} object.

     * Such configuration will cause a {@link SAXException}

     * exception when those properties are set on a {@link SAXParser}.

     *

     * <h3>Note for implementors</h3>

     * <p>

     * A parser must be able to work with any {@link Schema}

     * implementation. However, parsers and schemas are allowed

     * to use implementation-specific custom mechanisms

     * as long as they yield the result described in the specification.

     *

     * @param schema {@code Schema} to use, {@code null} to remove a schema.

     *

     * @throws UnsupportedOperationException When implementation does not

     *   override this method

     *

     * @since 1.5

     */

    public void setSchema(Schema schema) {

        throw new UnsupportedOperationException(

            "This parser does not support specification \""

            + this.getClass().getPackage().getSpecificationTitle()

            + "\" version \""

            + this.getClass().getPackage().getSpecificationVersion()

            + "\""

            );

    }

    /**

     * Set state of XInclude processing.

     *

     * <p>If XInclude markup is found in the document instance, should it be

     * processed as specified in <a href="http://www.w3.org/TR/xinclude/">

     * XML Inclusions (XInclude) Version 1.0</a>.

     *

     * <p>XInclude processing defaults to {@code false}.

     *

     * @param state Set XInclude processing to {@code true} or

     *   {@code false}

     *

     * @throws UnsupportedOperationException When implementation does not

     *   override this method

     *

     * @since 1.5

     */

    public void setXIncludeAware(final boolean state) {

        if (state) {

            throw new UnsupportedOperationException(" setXIncludeAware " +

                "is not supported on this JAXP"  +

                " implementation or earlier: " + this.getClass());

        }

    }

    /**

     * Get state of XInclude processing.

     *

     * @return current state of XInclude processing

     *

     * @throws UnsupportedOperationException When implementation does not

     *   override this method

     *

     * @since 1.5

     */

    public boolean isXIncludeAware() {

        throw new UnsupportedOperationException(

            "This parser does not support specification \""

            + this.getClass().getPackage().getSpecificationTitle()

            + "\" version \""

            + this.getClass().getPackage().getSpecificationVersion()

            + "\""

            );

    }

}