001    /* XMLInputFactory.java --
002       Copyright (C) 2005,2006,2009  Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    package javax.xml.stream;
039    
040    import java.io.BufferedReader;
041    import java.io.File;
042    import java.io.FileInputStream;
043    import java.io.InputStream;
044    import java.io.InputStreamReader;
045    import java.io.IOException;
046    import java.io.Reader;
047    import java.util.Properties;
048    import javax.xml.stream.util.XMLEventAllocator;
049    import javax.xml.transform.Source;
050    
051    /**
052     * Factory for creating stream and event readers from various kinds of input
053     * source.
054     * <h3>Parameters</h3>
055     * <table>
056     * <tr>
057     * <th>Name</th>
058     * <th>Description</th>
059     * <th>Type</th>
060     * <th>Default</th>
061     * <th>Required</th>
062     * </tr>
063     * <tr>
064     * <td>javax.xml.stream.isValidating</td>
065     * <td>Controls DTD validation</td>
066     * <td>Boolean</td>
067     * <td>Boolean.FALSE</td>
068     * <td>no</td>
069     * </tr>
070     * <tr>
071     * <td>javax.xml.stream.isNamespaceAware</td>
072     * <td>Controls namespace processing for XML 1.0</td>
073     * <td>Boolean</td>
074     * <td>Boolean.TRUE</td>
075     * <td>true is required, false is optional</td>
076     * </tr>
077     * <tr>
078     * <td>javax.xml.stream.isCoalescing</td>
079     * <td>Controls coalescing (normalization of adjacent character data)</td>
080     * <td>Boolean</td>
081     * <td>Boolean.FALSE</td>
082     * <td>yes</td>
083     * </tr>
084     * <tr>
085     * <td>javax.xml.stream.isReplacingEntityReferences</td>
086     * <td>Controls replacement of entity references with their replacement
087     * text</td>
088     * <td>Boolean</td>
089     * <td>Boolean.TRUE</td>
090     * <td>yes</td>
091     * </tr>
092     * <tr>
093     * <td>javax.xml.stream.isSupportingExternalEntities</td>
094     * <td>Controls whether to resolve external entities</td>
095     * <td>Boolean</td>
096     * <td>not specified</td>
097     * <td>yes</td>
098     * </tr>
099     * <tr>
100     * <td>javax.xml.stream.supportDTD</td>
101     * <td>Controls whether to support DTDs</td>
102     * <td>Boolean</td>
103     * <td>Boolean.TRUE</td>
104     * <td>yes</td>
105     * </tr>
106     * <tr>
107     * <td>javax.xml.stream.reporter</td>
108     * <td></td>
109     * <td>javax.xml.stream.XMLReporter</td>
110     * <td></td>
111     * <td>yes</td>
112     * </tr>
113     * <tr>
114     * <td>javax.xml.stream.resolver</td>
115     * <td></td>
116     * <td>javax.xml.stream.XMLResolver</td>
117     * <td></td>
118     * <td>yes</td>
119     * </tr>
120     * <tr>
121     * <td>javax.xml.stream.allocator</td>
122     * <td></td>
123     * <td>javax.xml.stream.util.XMLEventAllocator</td>
124     * <td></td>
125     * <td>yes</td>
126     * </tr>
127     * </table>
128     */
129    public abstract class XMLInputFactory
130    {
131    
132      /**
133       * Property used to control namespace support.
134       */
135      public static final String IS_NAMESPACE_AWARE =
136        "javax.xml.stream.isNamespaceAware";
137    
138      /**
139       * Property used to control DTD validation.
140       */
141      public static final String IS_VALIDATING = "javax.xml.stream.isValidating";
142    
143      /**
144       * Property used to control whether to coalesce adjacent text events.
145       */
146      public static final String IS_COALESCING = "javax.xml.stream.isCoalescing";
147    
148      /**
149       * Property used to control whether to replace entity references with
150       * their replacement text.
151       */
152      public static final String IS_REPLACING_ENTITY_REFERENCES =
153        "javax.xml.stream.isReplacingEntityReferences";
154    
155      /**
156       * Property used to control whether to resolve external entities.
157       */
158      public static final String IS_SUPPORTING_EXTERNAL_ENTITIES =
159        "javax.xml.stream.isSupportingExternalEntities";
160    
161      /**
162       * Property used to indicate whether to support DTDs.
163       */
164      public static final String SUPPORT_DTD = "javax.xml.stream.supportDTD";
165    
166      /**
167       * Property used to control the error reporter implementation.
168       */
169      public static final String REPORTER = "javax.xml.stream.reporter";
170    
171      /**
172       * Property used to control the entity resolver implementation.
173       */
174      public static final String RESOLVER = "javax.xml.stream.resolver";
175    
176      /**
177       * Property used to control the event allocator implementation.
178       */
179      public static final String ALLOCATOR = "javax.xml.stream.allocator";
180    
181      protected XMLInputFactory()
182      {
183      }
184    
185      /**
186       * Creates a new factory instance.
187       * @see #newInstance(String,ClassLoader)
188       */
189      public static XMLInputFactory newInstance()
190        throws FactoryConfigurationError
191      {
192        return newInstance(null, null);
193      }
194    
195      /**
196       * Creates a new factory instance.
197       * The implementation class to load is the first found in the following
198       * locations:
199       * <ol>
200       * <li>the <code>javax.xml.stream.XMLInputFactory</code> system
201       * property</li>
202       * <li>the above named property value in the
203       * <code><i>$JAVA_HOME</i>/lib/stax.properties</code> file</li>
204       * <li>the class name specified in the
205       * <code>META-INF/services/javax.xml.stream.XMLInputFactory</code>
206       * system resource</li>
207       * <li>the default factory class</li>
208       * </ol>
209       * @param factoryId name of the factory, same as a property name
210       * @param classLoader the class loader to use
211       * @return the factory implementation
212       * @exception FactoryConfigurationError if an instance of this factory
213       * cannot be loaded
214       */
215      public static XMLInputFactory newInstance(String factoryId,
216                                                ClassLoader classLoader)
217        throws FactoryConfigurationError
218      {
219        ClassLoader loader = classLoader;
220        if (loader == null)
221          {
222            loader = Thread.currentThread().getContextClassLoader();
223          }
224        if (loader == null)
225          {
226            loader = XMLInputFactory.class.getClassLoader();
227          }
228        String className = null;
229        int count = 0;
230        do
231          {
232            className = getFactoryClassName(loader, count++);
233            if (className != null)
234              {
235                try
236                  {
237                    Class<?> t = (loader != null) ? loader.loadClass(className) :
238                      Class.forName(className);
239                    return (XMLInputFactory) t.newInstance();
240                  }
241                catch (ClassNotFoundException e)
242                  {
243                    className = null;
244                  }
245                catch (Exception e)
246                  {
247                    throw new FactoryConfigurationError(e,
248                         "error instantiating class " + className);
249                  }
250              }
251          }
252        while (className == null && count < 3);
253        return new gnu.xml.stream.XMLInputFactoryImpl();
254      }
255    
256      private static String getFactoryClassName(ClassLoader loader, int attempt)
257      {
258        final String propertyName = "javax.xml.stream.XMLInputFactory";
259        switch (attempt)
260          {
261            case 0:
262              return System.getProperty(propertyName);
263            case 1:
264              try
265                {
266                  File file = new File(System.getProperty("java.home"));
267                  file = new File(file, "lib");
268                  file = new File(file, "stax.properties");
269                  InputStream in = new FileInputStream(file);
270                  Properties props = new Properties();
271                  props.load(in);
272                  in.close();
273                  return props.getProperty(propertyName);
274                }
275              catch (IOException e)
276                {
277                  return null;
278                }
279            case 2:
280              try
281                {
282                  String serviceKey = "/META-INF/services/" + propertyName;
283                  InputStream in = (loader != null) ?
284                     loader.getResourceAsStream(serviceKey) :
285                    XMLInputFactory.class.getResourceAsStream(serviceKey);
286                  if (in != null)
287                    {
288                      BufferedReader r =
289                         new BufferedReader(new InputStreamReader(in));
290                      String ret = r.readLine();
291                      r.close();
292                      return ret;
293                    }
294                }
295              catch (IOException e)
296                {
297                }
298              return null;
299            default:
300              return null;
301          }
302      }
303    
304      /**
305       * Creates a new stream reader.
306       */
307      public abstract XMLStreamReader createXMLStreamReader(Reader reader)
308        throws XMLStreamException;
309    
310      /**
311       * Creates a new stream reader.
312       */
313      public abstract XMLStreamReader createXMLStreamReader(Source source)
314        throws XMLStreamException;
315    
316      /**
317       * Creates a new stream reader.
318       */
319      public abstract XMLStreamReader createXMLStreamReader(InputStream stream)
320        throws XMLStreamException;
321    
322      /**
323       * Creates a new stream reader.
324       */
325      public abstract XMLStreamReader createXMLStreamReader(InputStream stream,
326                                                            String encoding)
327        throws XMLStreamException;
328    
329      /**
330       * Creates a new stream reader.
331       */
332      public abstract XMLStreamReader createXMLStreamReader(String systemId,
333                                                            InputStream stream)
334        throws XMLStreamException;
335    
336      /**
337       * Creates a new stream reader.
338       */
339      public abstract XMLStreamReader createXMLStreamReader(String systemId,
340                                                            Reader reader)
341        throws XMLStreamException;
342    
343      /**
344       * Creates a new event reader.
345       */
346      public abstract XMLEventReader createXMLEventReader(Reader reader)
347        throws XMLStreamException;
348    
349      /**
350       * Creates a new event reader.
351       */
352      public abstract XMLEventReader createXMLEventReader(String systemId,
353                                                          Reader reader)
354        throws XMLStreamException;
355    
356      /**
357       * Creates a new event reader.
358       */
359      public abstract XMLEventReader createXMLEventReader(XMLStreamReader reader)
360        throws XMLStreamException;
361    
362      /**
363       * Creates a new event reader.
364       */
365      public abstract XMLEventReader createXMLEventReader(Source source)
366        throws XMLStreamException;
367    
368      /**
369       * Creates a new event reader.
370       */
371      public abstract XMLEventReader createXMLEventReader(InputStream stream)
372        throws XMLStreamException;
373    
374      /**
375       * Creates a new event reader.
376       */
377      public abstract XMLEventReader createXMLEventReader(InputStream stream,
378                                                          String encoding)
379        throws XMLStreamException;
380    
381      /**
382       * Creates a new event reader.
383       */
384      public abstract XMLEventReader createXMLEventReader(String systemId,
385                                                          InputStream stream)
386        throws XMLStreamException;
387    
388      /**
389       * Create a new filtered reader.
390       */
391      public abstract XMLStreamReader createFilteredReader(XMLStreamReader reader,
392                                                           StreamFilter filter)
393        throws XMLStreamException;
394    
395      /**
396       * Create a new filtered reader.
397       */
398      public abstract XMLEventReader createFilteredReader(XMLEventReader reader,
399                                                          EventFilter filter)
400        throws XMLStreamException;
401    
402      /**
403       * Returns the entity resolver.
404       */
405      public abstract XMLResolver getXMLResolver();
406    
407      /**
408       * Sets the entity resolver.
409       */
410      public abstract void setXMLResolver(XMLResolver resolver);
411    
412      /**
413       * Returns the error reporter.
414       */
415      public abstract XMLReporter getXMLReporter();
416    
417      /**
418       * Sets the error reporter.
419       */
420      public abstract void setXMLReporter(XMLReporter reporter);
421    
422      /**
423       * Sets the implementation-specific property of the given name.
424       * @exception IllegalArgumentException if the property is not supported
425       */
426      public abstract void setProperty(String name, Object value)
427        throws IllegalArgumentException;
428    
429      /**
430       * Returns the implementation-specific property of the given name.
431       * @exception IllegalArgumentException if the property is not supported
432       */
433      public abstract Object getProperty(String name)
434        throws IllegalArgumentException;
435    
436      /**
437       * Indicates whether the specified property is supported.
438       */
439      public abstract boolean isPropertySupported(String name);
440    
441      /**
442       * Sets the event allocator.
443       */
444      public abstract void setEventAllocator(XMLEventAllocator allocator);
445    
446      /**
447       * Returns the event allocator.
448       */
449      public abstract XMLEventAllocator getEventAllocator();
450    
451    }