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  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
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  25 
  26 package javax.xml.parsers;
  27 
  28 import com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl;
  29 import javax.xml.validation.Schema;
  30 import org.xml.sax.SAXException;
  31 import org.xml.sax.SAXNotRecognizedException;
  32 import org.xml.sax.SAXNotSupportedException;
  33 
  34 /**
  35  * Defines a factory API that enables applications to configure and
  36  * obtain a SAX based parser to parse XML documents.
  37  *
  38  * @author Jeff Suttor
  39  * @author Neeraj Bajaj
  40  *
  41  * @since 1.4
  42  */
  43 public abstract class SAXParserFactory {
  44     private static final String DEFAULT_IMPL =
  45             "com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl";
  46 
  47     /**
  48      * Should Parsers be validating?
  49      */
  50     private boolean validating = false;
  51 
  52     /**
  53      * Should Parsers be namespace aware?
  54      */
  55     private boolean namespaceAware = false;
  56 
  57     /**
  58      * Protected constructor to force use of {@link #newInstance()}.
  59      */
  60     protected SAXParserFactory () {
  61 
  62     }
  63 
  64     /**
  65      * Creates a new NamespaceAware instance of the {@code SAXParserFactory}
  66      * builtin system-default implementation. Parsers produced by the factory
  67      * instance provides support for XML namespaces by default.
  68      *
  69      * @implSpec
  70      * In addition to creating a factory instance using the same process as
  71      * {@link #newDefaultInstance()}, this method must set NamespaceAware to true.
  72      *
  73      * @return a new instance of the {@code SAXParserFactory} builtin
  74      *         system-default implementation.
  75      *
  76      * @since 13
  77      */
  78     public static SAXParserFactory newDefaultNSInstance() {
  79         return makeNSAware(new SAXParserFactoryImpl());
  80     }
  81 
  82     /**
  83      * Creates a new NamespaceAware instance of a {@code SAXParserFactory}.
  84      * Parsers produced by the factory instance provides support for XML
  85      * namespaces by default.
  86      *
  87      * @implSpec
  88      * In addition to creating a factory instance using the same process as
  89      * {@link #newInstance()}, this method must set NamespaceAware to true.
  90      *
  91      * @return a new instance of the {@code SAXParserFactory}
  92      *
  93      * @throws FactoryConfigurationError in case of {@linkplain
  94      *         java.util.ServiceConfigurationError service configuration error}
  95      *         or if the implementation is not available or cannot be instantiated.
  96      *
  97      * @since 13
  98      */
  99     public static SAXParserFactory newNSInstance() {
 100         return makeNSAware(FactoryFinder.find(SAXParserFactory.class, DEFAULT_IMPL));
 101     }
 102 
 103     /**
 104      * Creates a new NamespaceAware instance of a {@code SAXParserFactory} from
 105      * the class name. Parsers produced by the factory instance provides
 106      * support for XML namespaces by default.
 107      *
 108      * @implSpec
 109      * In addition to creating a factory instance using the same process as
 110      * {@link #newInstance(java.lang.String, java.lang.ClassLoader)}, this method
 111      * must set NamespaceAware to true.
 112      *
 113      * @param factoryClassName a fully qualified factory class name that provides
 114      *                         implementation of
 115      *                         {@code javax.xml.parsers.SAXParserFactory}.
 116      *
 117      * @param classLoader the {@code ClassLoader} used to load the factory class.
 118      *                    If it is {@code null}, the current {@code Thread}'s
 119      *                    context classLoader is used to load the factory class.
 120      *
 121      * @return a new instance of the {@code SAXParserFactory}
 122      *
 123      * @throws FactoryConfigurationError if {@code factoryClassName} is {@code null}, or
 124      *                                   the factory class cannot be loaded, instantiated.
 125      *
 126      * @since 13
 127      */
 128     public static SAXParserFactory newNSInstance(String factoryClassName,
 129             ClassLoader classLoader) {
 130             return makeNSAware(FactoryFinder.newInstance(
 131                     SAXParserFactory.class, factoryClassName, classLoader, false));
 132     }
 133 
 134     /**
 135      * Creates a new instance of the {@code SAXParserFactory} builtin
 136      * system-default implementation.
 137      *
 138      * @return A new instance of the {@code SAXParserFactory} builtin
 139      *         system-default implementation.
 140      *
 141      * @since 9
 142      */
 143     public static SAXParserFactory newDefaultInstance() {
 144         return new SAXParserFactoryImpl();
 145     }
 146 
 147     /**
 148      * Obtain a new instance of a {@code SAXParserFactory}. This
 149      * static method creates a new factory instance
 150      * This method uses the following ordered lookup procedure to determine
 151      * the {@code SAXParserFactory} implementation class to
 152      * load:
 153      * <ul>
 154      * <li>
 155      * Use the {@code javax.xml.parsers.SAXParserFactory} system
 156      * property.
 157      * </li>
 158      * <li>
 159      * <p>
 160      * Use the configuration file "jaxp.properties". The file is in standard
 161      * {@link java.util.Properties} format and typically located in the
 162      * {@code conf} directory of the Java installation. It contains the fully qualified
 163      * name of the implementation class with the key being the system property
 164      * defined above.
 165      * <p>
 166      * The jaxp.properties file is read only once by the JAXP implementation
 167      * and its values are then cached for future use.  If the file does not exist
 168      * when the first attempt is made to read from it, no further attempts are
 169      * made to check for its existence.  It is not possible to change the value
 170      * of any property in jaxp.properties after it has been read for the first time.
 171      * </li>
 172      * <li>
 173      * <p>
 174      * Use the service-provider loading facility, defined by the
 175      * {@link java.util.ServiceLoader} class, to attempt to locate and load an
 176      * implementation of the service using the {@linkplain
 177      * java.util.ServiceLoader#load(java.lang.Class) default loading mechanism}:
 178      * the service-provider loading facility will use the {@linkplain
 179      * java.lang.Thread#getContextClassLoader() current thread's context class loader}
 180      * to attempt to load the service. If the context class
 181      * loader is null, the {@linkplain
 182      * ClassLoader#getSystemClassLoader() system class loader} will be used.
 183      * </li>
 184      * <li>
 185      * <p>
 186      * Otherwise, the {@linkplain #newDefaultInstance() system-default}
 187      * implementation is returned.
 188      * </li>
 189      * </ul>
 190      *
 191      * <p>
 192      * Once an application has obtained a reference to a
 193      * {@code SAXParserFactory} it can use the factory to
 194      * configure and obtain parser instances.
 195      *
 196      *
 197      *
 198      * <h4>Tip for Trouble-shooting</h4>
 199      * <p>
 200      * Setting the {@code jaxp.debug} system property will cause
 201      * this method to print a lot of debug messages
 202      * to {@code System.err} about what it is doing and where it is looking at.
 203      *
 204      * <p>
 205      * If you have problems loading {@link SAXParser}s, try:
 206      * <pre>
 207      * java -Djaxp.debug=1 YourProgram ....
 208      * </pre>
 209      *
 210      *
 211      * @return A new instance of a SAXParserFactory.
 212      *
 213      * @throws FactoryConfigurationError in case of {@linkplain
 214      * java.util.ServiceConfigurationError service configuration error} or if
 215      * the implementation is not available or cannot be instantiated.
 216      */
 217 
 218     public static SAXParserFactory newInstance() {
 219         return FactoryFinder.find(
 220                 /* The default property name according to the JAXP spec */
 221                 SAXParserFactory.class,
 222                 /* The fallback implementation class name */
 223                 DEFAULT_IMPL);
 224     }
 225 
 226     /**
 227      * Obtain a new instance of a {@code SAXParserFactory} from class name.
 228      * This function is useful when there are multiple providers in the classpath.
 229      * It gives more control to the application as it can specify which provider
 230      * should be loaded.
 231      *
 232      * <p>Once an application has obtained a reference to a {@code SAXParserFactory}
 233      * it can use the factory to configure and obtain parser instances.
 234      *
 235      *
 236      * <h4>Tip for Trouble-shooting</h4>
 237      * <p>Setting the {@code jaxp.debug} system property will cause
 238      * this method to print a lot of debug messages
 239      * to {@code System.err} about what it is doing and where it is looking at.
 240      *
 241      * <p>
 242      * If you have problems, try:
 243      * <pre>
 244      * java -Djaxp.debug=1 YourProgram ....
 245      * </pre>
 246      *
 247      * @param factoryClassName fully qualified factory class name that provides implementation of {@code javax.xml.parsers.SAXParserFactory}.
 248      *
 249      * @param classLoader {@code ClassLoader} used to load the factory class. If {@code null}
 250      *                     current {@code Thread}'s context classLoader is used to load the factory class.
 251      *
 252      * @return New instance of a {@code SAXParserFactory}
 253      *
 254      * @throws FactoryConfigurationError if {@code factoryClassName} is {@code null}, or
 255      *                                   the factory class cannot be loaded, instantiated.
 256      *
 257      * @see #newInstance()
 258      *
 259      * @since 1.6
 260      */
 261     public static SAXParserFactory newInstance(String factoryClassName, ClassLoader classLoader){
 262             //do not fallback if given classloader can't find the class, throw exception
 263             return FactoryFinder.newInstance(SAXParserFactory.class,
 264                     factoryClassName, classLoader, false);
 265     }
 266 
 267     private static SAXParserFactory makeNSAware(SAXParserFactory spf) {
 268         spf.setNamespaceAware(true);
 269         return spf;
 270     }
 271 
 272     /**
 273      * Creates a new instance of a SAXParser using the currently
 274      * configured factory parameters.
 275      *
 276      * @return A new instance of a SAXParser.
 277      *
 278      * @throws ParserConfigurationException if a parser cannot
 279      *   be created which satisfies the requested configuration.
 280      * @throws SAXException for SAX errors.
 281      */
 282 
 283     public abstract SAXParser newSAXParser()
 284         throws ParserConfigurationException, SAXException;
 285 
 286 
 287     /**
 288      * Specifies that the parser produced by this code will
 289      * provide support for XML namespaces. By default the value of this is set
 290      * to {@code false}.
 291      *
 292      * @param awareness true if the parser produced by this code will
 293      *                  provide support for XML namespaces; false otherwise.
 294      */
 295 
 296     public void setNamespaceAware(boolean awareness) {
 297         this.namespaceAware = awareness;
 298     }
 299 
 300     /**
 301      * Specifies that the parser produced by this code will
 302      * validate documents as they are parsed. By default the value of this is
 303      * set to {@code false}.
 304      *
 305      * <p>
 306      * Note that "the validation" here means
 307      * <a href="http://www.w3.org/TR/REC-xml#proc-types">a validating
 308      * parser</a> as defined in the XML recommendation.
 309      * In other words, it essentially just controls the DTD validation.
 310      * (except the legacy two properties defined in JAXP 1.2.)
 311      *
 312      * <p>
 313      * To use modern schema languages such as W3C XML Schema or
 314      * RELAX NG instead of DTD, you can configure your parser to be
 315      * a non-validating parser by leaving the {@link #setValidating(boolean)}
 316      * method {@code false}, then use the {@link #setSchema(Schema)}
 317      * method to associate a schema to a parser.
 318      *
 319      * @param validating true if the parser produced by this code will
 320      *                   validate documents as they are parsed; false otherwise.
 321      */
 322 
 323     public void setValidating(boolean validating) {
 324         this.validating = validating;
 325     }
 326 
 327     /**
 328      * Indicates whether or not the factory is configured to produce
 329      * parsers which are namespace aware.
 330      *
 331      * @return true if the factory is configured to produce
 332      *         parsers which are namespace aware; false otherwise.
 333      */
 334 
 335     public boolean isNamespaceAware() {
 336         return namespaceAware;
 337     }
 338 
 339     /**
 340      * Indicates whether or not the factory is configured to produce
 341      * parsers which validate the XML content during parse.
 342      *
 343      * @return true if the factory is configured to produce parsers which validate
 344      *         the XML content during parse; false otherwise.
 345      */
 346 
 347     public boolean isValidating() {
 348         return validating;
 349     }
 350 
 351     /**
 352      * Sets the particular feature in the underlying implementation of
 353      * org.xml.sax.XMLReader.
 354      * A list of the core features and properties can be found at
 355      * <a href="http://www.saxproject.org/">http://www.saxproject.org/</a>
 356      *
 357      * <p>All implementations are required to support the {@link javax.xml.XMLConstants#FEATURE_SECURE_PROCESSING} feature.
 358      * When the feature is
 359      * <ul>
 360      *   <li>
 361      *     {@code true}: the implementation will limit XML processing to conform to implementation limits.
 362      *     Examples include entity expansion limits and XML Schema constructs that would consume large amounts of resources.
 363      *     If XML processing is limited for security reasons, it will be reported via a call to the registered
 364      *     {@link org.xml.sax.ErrorHandler#fatalError(SAXParseException exception)}.
 365      *     See {@link SAXParser} {@code parse} methods for handler specification.
 366      *   </li>
 367      *   <li>
 368      *     When the feature is {@code false}, the implementation will processing XML according to the XML specifications without
 369      *     regard to possible implementation limits.
 370      *   </li>
 371      * </ul>
 372      *
 373      * @param name The name of the feature to be set.
 374      * @param value The value of the feature to be set.
 375      *
 376      * @throws ParserConfigurationException if a parser cannot
 377      *     be created which satisfies the requested configuration.
 378      * @throws SAXNotRecognizedException When the underlying XMLReader does
 379      *            not recognize the property name.
 380      * @throws SAXNotSupportedException When the underlying XMLReader
 381      *            recognizes the property name but doesn't support the
 382      *            property.
 383      * @throws NullPointerException If the {@code name} parameter is null.
 384      *
 385      * @see org.xml.sax.XMLReader#setFeature
 386      */
 387     public abstract void setFeature(String name, boolean value)
 388         throws ParserConfigurationException, SAXNotRecognizedException,
 389                 SAXNotSupportedException;
 390 
 391     /**
 392      *
 393      * Returns the particular property requested for in the underlying
 394      * implementation of org.xml.sax.XMLReader.
 395      *
 396      * @param name The name of the property to be retrieved.
 397      *
 398      * @return Value of the requested property.
 399      *
 400      * @throws ParserConfigurationException if a parser cannot be created which satisfies the requested configuration.
 401      * @throws SAXNotRecognizedException When the underlying XMLReader does not recognize the property name.
 402      * @throws SAXNotSupportedException When the underlying XMLReader recognizes the property name but doesn't support the property.
 403      *
 404      * @see org.xml.sax.XMLReader#getProperty
 405      */
 406     public abstract boolean getFeature(String name)
 407         throws ParserConfigurationException, SAXNotRecognizedException,
 408                 SAXNotSupportedException;
 409 
 410 
 411     /**
 412      * Gets the {@link Schema} object specified through
 413      * the {@link #setSchema(Schema schema)} method.
 414      *
 415      *
 416      * @throws UnsupportedOperationException When implementation does not
 417      *   override this method
 418      *
 419      * @return
 420      *      the {@link Schema} object that was last set through
 421      *      the {@link #setSchema(Schema)} method, or null
 422      *      if the method was not invoked since a {@link SAXParserFactory}
 423      *      is created.
 424      *
 425      * @since 1.5
 426      */
 427     public Schema getSchema() {
 428         throw new UnsupportedOperationException(
 429             "This parser does not support specification \""
 430             + this.getClass().getPackage().getSpecificationTitle()
 431             + "\" version \""
 432             + this.getClass().getPackage().getSpecificationVersion()
 433             + "\""
 434             );
 435     }
 436 
 437     /**
 438      * Set the {@link Schema} to be used by parsers created
 439      * from this factory.
 440      *
 441      * <p>When a {@link Schema} is non-null, a parser will use a validator
 442      * created from it to validate documents before it passes information
 443      * down to the application.
 444      *
 445      * <p>When warnings/errors/fatal errors are found by the validator, the parser must
 446      * handle them as if those errors were found by the parser itself.
 447      * In other words, if the user-specified {@link org.xml.sax.ErrorHandler}
 448      * is set, it must receive those errors, and if not, they must be
 449      * treated according to the implementation specific
 450      * default error handling rules.
 451      *
 452      * <p>A validator may modify the SAX event stream (for example by
 453      * adding default values that were missing in documents), and a parser
 454      * is responsible to make sure that the application will receive
 455      * those modified event stream.
 456      *
 457      * <p>Initially, {@code null} is set as the {@link Schema}.
 458      *
 459      * <p>This processing will take effect even if
 460      * the {@link #isValidating()} method returns {@code false}.
 461      *
 462      * <p>It is an error to use
 463      * the {@code http://java.sun.com/xml/jaxp/properties/schemaSource}
 464      * property and/or the {@code http://java.sun.com/xml/jaxp/properties/schemaLanguage}
 465      * property in conjunction with a non-null {@link Schema} object.
 466      * Such configuration will cause a {@link SAXException}
 467      * exception when those properties are set on a {@link SAXParser}.
 468      *
 469      * <h4>Note for implementors</h4>
 470      * <p>
 471      * A parser must be able to work with any {@link Schema}
 472      * implementation. However, parsers and schemas are allowed
 473      * to use implementation-specific custom mechanisms
 474      * as long as they yield the result described in the specification.
 475      *
 476      * @param schema {@code Schema} to use, {@code null} to remove a schema.
 477      *
 478      * @throws UnsupportedOperationException When implementation does not
 479      *   override this method
 480      *
 481      * @since 1.5
 482      */
 483     public void setSchema(Schema schema) {
 484         throw new UnsupportedOperationException(
 485             "This parser does not support specification \""
 486             + this.getClass().getPackage().getSpecificationTitle()
 487             + "\" version \""
 488             + this.getClass().getPackage().getSpecificationVersion()
 489             + "\""
 490             );
 491     }
 492 
 493     /**
 494      * Set state of XInclude processing.
 495      *
 496      * <p>If XInclude markup is found in the document instance, should it be
 497      * processed as specified in <a href="http://www.w3.org/TR/xinclude/">
 498      * XML Inclusions (XInclude) Version 1.0</a>.
 499      *
 500      * <p>XInclude processing defaults to {@code false}.
 501      *
 502      * @param state Set XInclude processing to {@code true} or
 503      *   {@code false}
 504      *
 505      * @throws UnsupportedOperationException When implementation does not
 506      *   override this method
 507      *
 508      * @since 1.5
 509      */
 510     public void setXIncludeAware(final boolean state) {
 511         if (state) {
 512             throw new UnsupportedOperationException(" setXIncludeAware " +
 513                 "is not supported on this JAXP"  +
 514                 " implementation or earlier: " + this.getClass());
 515         }
 516     }
 517 
 518     /**
 519      * Get state of XInclude processing.
 520      *
 521      * @return current state of XInclude processing
 522      *
 523      * @throws UnsupportedOperationException When implementation does not
 524      *   override this method
 525      *
 526      * @since 1.5
 527      */
 528     public boolean isXIncludeAware() {
 529         throw new UnsupportedOperationException(
 530             "This parser does not support specification \""
 531             + this.getClass().getPackage().getSpecificationTitle()
 532             + "\" version \""
 533             + this.getClass().getPackage().getSpecificationVersion()
 534             + "\""
 535             );
 536     }
 537 }