001    /* XMLInputFactory.java -- 
002       Copyright (C) 2005,2006  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       */
210      public static XMLInputFactory newInstance(String factoryId,
211                                                ClassLoader classLoader)
212        throws FactoryConfigurationError
213      {
214        ClassLoader loader = classLoader;
215        if (loader == null)
216          {
217            loader = Thread.currentThread().getContextClassLoader();
218          }
219        if (loader == null)
220          {
221            loader = XMLInputFactory.class.getClassLoader();
222          }
223        String className = null;
224        int count = 0;
225        do
226          {
227            className = getFactoryClassName(loader, count++);
228            if (className != null)
229              {
230                try
231                  {
232                    Class<?> t = (loader != null) ? loader.loadClass(className) :
233                      Class.forName(className);
234                    return (XMLInputFactory) t.newInstance();
235                  }
236                catch (ClassNotFoundException e)
237                  {
238                    className = null;
239                  }
240                catch (Exception e)
241                  {
242                    throw new FactoryConfigurationError(e,
243                         "error instantiating class " + className);
244                  }
245              }
246          }
247        while (className == null && count < 3);
248        return new gnu.xml.stream.XMLInputFactoryImpl();
249      }
250    
251      private static String getFactoryClassName(ClassLoader loader, int attempt)
252      {
253        final String propertyName = "javax.xml.stream.XMLInputFactory";
254        switch (attempt)
255          {
256            case 0:
257              return System.getProperty(propertyName);
258            case 1:
259              try
260                {
261                  File file = new File(System.getProperty("java.home"));
262                  file = new File(file, "lib");
263                  file = new File(file, "stax.properties");
264                  InputStream in = new FileInputStream(file);
265                  Properties props = new Properties();
266                  props.load(in);
267                  in.close();
268                  return props.getProperty(propertyName);
269                }
270              catch (IOException e)
271                {
272                  return null;
273                }
274            case 2:
275              try
276                {
277                  String serviceKey = "/META-INF/services/" + propertyName;
278                  InputStream in = (loader != null) ?
279                     loader.getResourceAsStream(serviceKey) :
280                    XMLInputFactory.class.getResourceAsStream(serviceKey);
281                  if (in != null)
282                    {
283                      BufferedReader r =
284                         new BufferedReader(new InputStreamReader(in));
285                      String ret = r.readLine();
286                      r.close();
287                      return ret;
288                    }
289                }
290              catch (IOException e)
291                {
292                }
293              return null;
294            default:
295              return null;
296          }
297      }
298    
299      /**
300       * Creates a new stream reader.
301       */
302      public abstract XMLStreamReader createXMLStreamReader(Reader reader)
303        throws XMLStreamException;
304    
305      /**
306       * Creates a new stream reader.
307       */
308      public abstract XMLStreamReader createXMLStreamReader(Source source)
309        throws XMLStreamException;
310    
311      /**
312       * Creates a new stream reader.
313       */
314      public abstract XMLStreamReader createXMLStreamReader(InputStream stream)
315        throws XMLStreamException;
316    
317      /**
318       * Creates a new stream reader.
319       */
320      public abstract XMLStreamReader createXMLStreamReader(InputStream stream,
321                                                            String encoding)
322        throws XMLStreamException;
323    
324      /**
325       * Creates a new stream reader.
326       */
327      public abstract XMLStreamReader createXMLStreamReader(String systemId,
328                                                            InputStream stream)
329        throws XMLStreamException;
330    
331      /**
332       * Creates a new stream reader.
333       */
334      public abstract XMLStreamReader createXMLStreamReader(String systemId,
335                                                            Reader reader)
336        throws XMLStreamException;
337    
338      /**
339       * Creates a new event reader.
340       */
341      public abstract XMLEventReader createXMLEventReader(Reader reader)
342        throws XMLStreamException;
343    
344      /**
345       * Creates a new event reader.
346       */
347      public abstract XMLEventReader createXMLEventReader(String systemId,
348                                                          Reader reader)
349        throws XMLStreamException;
350      
351      /**
352       * Creates a new event reader.
353       */
354      public abstract XMLEventReader createXMLEventReader(XMLStreamReader reader)
355        throws XMLStreamException;
356    
357      /**
358       * Creates a new event reader.
359       */
360      public abstract XMLEventReader createXMLEventReader(Source source)
361        throws XMLStreamException;
362    
363      /**
364       * Creates a new event reader.
365       */
366      public abstract XMLEventReader createXMLEventReader(InputStream stream)
367        throws XMLStreamException;
368    
369      /**
370       * Creates a new event reader.
371       */
372      public abstract XMLEventReader createXMLEventReader(InputStream stream,
373                                                          String encoding)
374        throws XMLStreamException;
375    
376      /**
377       * Creates a new event reader.
378       */
379      public abstract XMLEventReader createXMLEventReader(String systemId,
380                                                          InputStream stream)
381        throws XMLStreamException;
382    
383      /**
384       * Create a new filtered reader.
385       */
386      public abstract XMLStreamReader createFilteredReader(XMLStreamReader reader,
387                                                           StreamFilter filter)
388        throws XMLStreamException;
389    
390      /**
391       * Create a new filtered reader.
392       */
393      public abstract XMLEventReader createFilteredReader(XMLEventReader reader,
394                                                          EventFilter filter)
395        throws XMLStreamException;
396    
397      /**
398       * Returns the entity resolver.
399       */
400      public abstract XMLResolver getXMLResolver();
401    
402      /**
403       * Sets the entity resolver.
404       */
405      public abstract void setXMLResolver(XMLResolver resolver);
406    
407      /**
408       * Returns the error reporter.
409       */
410      public abstract XMLReporter getXMLReporter();
411    
412      /**
413       * Sets the error reporter.
414       */
415      public abstract void setXMLReporter(XMLReporter reporter);
416    
417      /**
418       * Sets the implementation-specific property of the given name.
419       * @exception IllegalArgumentException if the property is not supported
420       */
421      public abstract void setProperty(String name, Object value)
422        throws IllegalArgumentException;
423    
424      /**
425       * Returns the implementation-specific property of the given name.
426       * @exception IllegalArgumentException if the property is not supported
427       */
428      public abstract Object getProperty(String name)
429        throws IllegalArgumentException;
430    
431      /**
432       * Indicates whether the specified property is supported.
433       */
434      public abstract boolean isPropertySupported(String name);
435    
436      /**
437       * Sets the event allocator.
438       */
439      public abstract void setEventAllocator(XMLEventAllocator allocator);
440    
441      /**
442       * Returns the event allocator.
443       */
444      public abstract XMLEventAllocator getEventAllocator();
445    
446    }
447