java/11 : java.xml/javax/xml/parsers/SAXParserFactory.java

SAXParserFactory
https://openjdk.java.net/
GPLv2 + Classpath Exception
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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.
Author: Jeff Suttor, Neeraj Bajaj
Since: 1.4/**
 * Defines a factory API that enables applications to configure and
 * obtain a SAX based parser to parse XML documents.
 *
 * @author Jeff Suttor
 * @author Neeraj Bajaj
 *
 * @since 1.4
 */
public abstract class SAXParserFactory {

    Should Parsers be validating?
/**
     * Should Parsers be validating?
     */
    private boolean validating = false;

    Should Parsers be namespace aware?
/**
     * Should Parsers be namespace aware?
     */
    private boolean namespaceAware = false;

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

    }

    Creates a new instance of the SAXParserFactory builtin system-default implementation. 
Returns: A new instance of the SAXParserFactory builtin system-default implementation.
Since: 9/**
     * 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 SAXParserFactory. This static method creates a new factory instance This method uses the following ordered lookup procedure to determine the SAXParserFactory implementation class to load: 
 Use the javax.xml.parsers.SAXParserFactory 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 SAXParserFactory it can use the factory to configure and obtain parser 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 loading SAXParsers, try: 
java -Djaxp.debug=1 YourProgram ....

Throws: FactoryConfigurationError – in case of service configuration error or if the implementation is not available or cannot be instantiated.
Returns: A new instance of a SAXParserFactory./**
     * 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 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. Once an application has obtained a reference to a SAXParserFactory it can use the factory to configure and obtain parser 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.parsers.SAXParserFactory.
classLoader – ClassLoader used to load the factory class. If null current Thread's context classLoader is used to load the factory class.
Throws: FactoryConfigurationError – if factoryClassName is null, or the factory class cannot be loaded, instantiated.
See Also: newInstance()
Returns: New instance of a SAXParserFactory
Since: 1.6/**
     * 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.
Throws: ParserConfigurationException – if a parser cannot
  be created which satisfies the requested configuration.
SAXException – for SAX errors.
Returns: A new instance of a SAXParser./**
     * 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 false. 
Params: awareness – true if the parser produced by this code will
                 provide support for XML namespaces; false otherwise./**
     * 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 false. 
Note that "the validation" here means
a validating
parser 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.)
 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 setValidating(boolean) method false, then use the setSchema(Schema) method to associate a schema to a parser. 
Params: validating – true if the parser produced by this code will
                  validate documents as they are parsed; false otherwise./**
     * 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.
Returns: true if the factory is configured to produce
        parsers which are namespace aware; false otherwise./**
     * 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.
Returns: true if the factory is configured to produce parsers which validate
        the XML content during parse; false otherwise./**
     * 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
http://www.saxproject.org/
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. 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 ErrorHandler.fatalError(SAXParseException exception). See SAXParser parse methods for handler specification. 
   When the feature is false, the implementation will processing XML according to the XML specifications without regard to possible implementation limits. 

Params: name – The name of the feature to be set.
value – The value of the feature to be set.
Throws: ParserConfigurationException – if a parser cannot
    be created which satisfies the requested configuration.
SAXNotRecognizedException – When the underlying XMLReader does
           not recognize the property name.
SAXNotSupportedException – When the underlying XMLReader
           recognizes the property name but doesn't support the
           property.
NullPointerException – If the name parameter is null.
See Also: XMLReader.setFeature/**
     * 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.
Params: name – The name of the property to be retrieved.
Throws: ParserConfigurationException – if a parser cannot be created which satisfies the requested configuration.
SAXNotRecognizedException – When the underlying XMLReader does not recognize the property name.
SAXNotSupportedException – When the underlying XMLReader recognizes the property name but doesn't support the property.
See Also: XMLReader.getProperty
Returns: Value of the requested property./**
     *
     * 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 Schema object specified through the setSchema(Schema schema) method. 
Throws: UnsupportedOperationException – When implementation does not
  override this method
Returns:  the Schema object that was last set through the setSchema(Schema) method, or null if the method was not invoked since a SAXParserFactory is created.
Since: 1.5/**
     * 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 Schema to be used by parsers created from this factory. When a Schema is non-null, a parser will use a validator created from it to validate documents before it passes information down to the application. 
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 ErrorHandler is set, it must receive those errors, and if not, they must be treated according to the implementation specific default error handling rules. 
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.
Initially, null is set as the Schema. 
This processing will take effect even if the isValidating() method returns false. 
It is an error to use the http://java.sun.com/xml/jaxp/properties/schemaSource property and/or the http://java.sun.com/xml/jaxp/properties/schemaLanguage property in conjunction with a non-null Schema object. Such configuration will cause a SAXException exception when those properties are set on a SAXParser. 
Note for implementors
 A parser must be able to work with any 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. 
Params: schema – Schema to use, null to remove a schema.
Throws: UnsupportedOperationException – When implementation does not
  override this method
Since: 1.5/**
     * 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.
If XInclude markup is found in the document instance, should it be
processed as specified in 
XML Inclusions (XInclude) Version 1.0.
XInclude processing defaults to false. 
Params: state – Set XInclude processing to true or false
Throws: UnsupportedOperationException – When implementation does not
  override this method
Since: 1.5/**
     * 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.
Throws: UnsupportedOperationException – When implementation does not
  override this method
Returns: current state of XInclude processing
Since: 1.5/**
     * 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()
            + "\""
            );
    }
}
Returns:	A new instance of the `SAXParserFactory` builtin system-default implementation.
Since:	9
Throws:	FactoryConfigurationError – in case of service configuration error or if the implementation is not available or cannot be instantiated.
Returns:	A new instance of a SAXParserFactory.
Params:	factoryClassName – fully qualified factory class name that provides implementation of `javax.xml.parsers.SAXParserFactory`. classLoader – `ClassLoader` used to load the factory class. If `null` current `Thread`'s context classLoader is used to load the factory class.
Throws:	FactoryConfigurationError – if `factoryClassName` is `null`, or the factory class cannot be loaded, instantiated.
See Also:	newInstance()
Returns:	New instance of a `SAXParserFactory`
Since:	1.6
Throws:	ParserConfigurationException – if a parser cannot be created which satisfies the requested configuration. SAXException – for SAX errors.
Returns:	A new instance of a SAXParser.
Params:	name – The name of the feature to be set. value – The value of the feature to be set.
Throws:	ParserConfigurationException – if a parser cannot be created which satisfies the requested configuration. SAXNotRecognizedException – When the underlying XMLReader does not recognize the property name. SAXNotSupportedException – When the underlying XMLReader recognizes the property name but doesn't support the property. NullPointerException – If the `name` parameter is null.
See Also:	XMLReader.setFeature
Params:	name – The name of the property to be retrieved.
Throws:	ParserConfigurationException – if a parser cannot be created which satisfies the requested configuration. SAXNotRecognizedException – When the underlying XMLReader does not recognize the property name. SAXNotSupportedException – When the underlying XMLReader recognizes the property name but doesn't support the property.
See Also:	XMLReader.getProperty
Returns:	Value of the requested property.
Throws:	UnsupportedOperationException – When implementation does not override this method
Returns:	the `Schema` object that was last set through the `setSchema(Schema)` method, or null if the method was not invoked since a `SAXParserFactory` is created.
Since:	1.5
Params:	schema – `Schema` to use, `null` to remove a schema.
Throws:	UnsupportedOperationException – When implementation does not override this method
Since:	1.5
Params:	state – Set XInclude processing to `true` or `false`
Throws:	UnsupportedOperationException – When implementation does not override this method
Since:	1.5
/

java/ 11/ java.xml/javax/xml/parsers/SAXParserFactory.java

Tip for Trouble-shooting

Tip for Trouble-shooting

Note for implementors
