001 /* SchemaFactory.java --
002 Copyright (C) 2004, 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.validation;
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.net.URL;
047 import java.util.Properties;
048 import javax.xml.XMLConstants;
049 import javax.xml.transform.Source;
050 import javax.xml.transform.stream.StreamSource;
051 import org.w3c.dom.ls.LSResourceResolver;
052 import org.xml.sax.ErrorHandler;
053 import org.xml.sax.SAXException;
054 import org.xml.sax.SAXNotRecognizedException;
055 import org.xml.sax.SAXNotSupportedException;
056
057 /**
058 * Factory for obtaining schemata.
059 *
060 * @author Chris Burdess (dog@gnu.org)
061 * @since 1.5
062 */
063 public abstract class SchemaFactory
064 {
065 protected SchemaFactory()
066 {
067 }
068
069 /**
070 * Returns an implementation of <code>SchemaFactory</code> that supports
071 * the specified schema language.
072 * @param schemaLanguage the URI of a schema language (see
073 * <code>XMLConstants</code>)
074 */
075 public static final SchemaFactory newInstance(String schemaLanguage)
076 {
077 ClassLoader loader = Thread.currentThread().getContextClassLoader();
078 if (loader == null)
079 {
080 loader = SchemaFactory.class.getClassLoader();
081 }
082 final String factoryClassName = "javax.xml.validation.SchemaFactory";
083 String className = null;
084 int count = 0;
085 do
086 {
087 className = getFactoryClassName(loader, schemaLanguage, count++);
088 if (className != null)
089 {
090 try
091 {
092 Class<?> t = (loader != null) ? loader.loadClass(className) :
093 Class.forName(className);
094 return (SchemaFactory) t.newInstance();
095 }
096 catch (Exception e)
097 {
098 // Ignore any errors and continue algorithm.
099 // This method doesn't have a means of propagating
100 // class instantiation errors.
101 className = null;
102 }
103 }
104 }
105 while (className == null && count < 2);
106 try
107 {
108 String serviceKey = "/META-INF/services/" + factoryClassName;
109 InputStream in = (loader != null) ?
110 loader.getResourceAsStream(serviceKey) :
111 SchemaFactory.class.getResourceAsStream(serviceKey);
112 if (in != null)
113 {
114 BufferedReader r =
115 new BufferedReader(new InputStreamReader(in));
116 try
117 {
118 for (String line = r.readLine(); line != null;
119 line = r.readLine())
120 {
121 Class<?> t = (loader != null) ? loader.loadClass(className) :
122 Class.forName(className);
123 SchemaFactory ret = (SchemaFactory) t.newInstance();
124 if (ret.isSchemaLanguageSupported(schemaLanguage))
125 return ret;
126 }
127 }
128 catch (Exception e)
129 {
130 // Fall through. See above.
131 }
132 finally
133 {
134 r.close();
135 }
136 }
137 }
138 catch (IOException e)
139 {
140 }
141 // Default schema factories for Classpath
142 if (XMLConstants.W3C_XML_SCHEMA_NS_URI.equals(schemaLanguage))
143 return new gnu.xml.validation.xmlschema.XMLSchemaSchemaFactory();
144 if (XMLConstants.RELAXNG_NS_URI.equals(schemaLanguage))
145 return new gnu.xml.validation.relaxng.RELAXNGSchemaFactory();
146 throw new IllegalArgumentException(schemaLanguage);
147 }
148
149 private static String getFactoryClassName(ClassLoader loader,
150 String schemaLanguage, int attempt)
151 {
152 final String factoryClassName = "javax.xml.validation.SchemaFactory";
153 final String propertyName = factoryClassName + ":" + schemaLanguage;
154 switch (attempt)
155 {
156 case 0:
157 return System.getProperty(propertyName);
158 case 1:
159 try
160 {
161 File file = new File(System.getProperty("java.home"));
162 file = new File(file, "lib");
163 file = new File(file, "jaxp.properties");
164 InputStream in = new FileInputStream(file);
165 Properties props = new Properties();
166 props.load(in);
167 in.close();
168 return props.getProperty(propertyName);
169 }
170 catch (IOException e)
171 {
172 return null;
173 }
174 default:
175 return null;
176 }
177 }
178
179 /**
180 * Indicates whether the specified schema language is supported.
181 * @param schemaLanguage the URI of a schema language (see
182 * <code>XMLConstants</code>)
183 */
184 public abstract boolean isSchemaLanguageSupported(String schemaLanguage);
185
186 public boolean getFeature(String name)
187 throws SAXNotRecognizedException, SAXNotSupportedException
188 {
189 throw new SAXNotRecognizedException(name);
190 }
191
192 public void setFeature(String name, boolean value)
193 throws SAXNotRecognizedException, SAXNotSupportedException
194 {
195 throw new SAXNotRecognizedException(name);
196 }
197
198 public Object getProperty(String name)
199 throws SAXNotRecognizedException, SAXNotSupportedException
200 {
201 throw new SAXNotRecognizedException(name);
202 }
203
204 public void setProperty(String name, Object value)
205 throws SAXNotRecognizedException, SAXNotSupportedException
206 {
207 throw new SAXNotRecognizedException(name);
208 }
209
210 public abstract ErrorHandler getErrorHandler();
211
212 public abstract void setErrorHandler(ErrorHandler errorHandler);
213
214 public abstract LSResourceResolver getResourceResolver();
215
216 public abstract void setResourceResolver(LSResourceResolver resourceResolver);
217
218 /**
219 * Returns a schema based on the specified source resource.
220 * @param schema the source resource
221 */
222 public Schema newSchema(Source schema)
223 throws SAXException
224 {
225 return newSchema(new Source[] { schema });
226 }
227
228 /**
229 * Returns a schema based on the specified source file.
230 * @param schema the source resource
231 */
232 public Schema newSchema(File schema)
233 throws SAXException
234 {
235 return newSchema(new StreamSource(schema));
236 }
237
238 /**
239 * Returns a schema based on the specified URL.
240 * @param schema the source resource
241 */
242 public Schema newSchema(URL schema)
243 throws SAXException
244 {
245 return newSchema(new StreamSource(schema.toString()));
246 }
247
248 /**
249 * Parses the specified sources, and combine them into a single schema.
250 * The exact procedure and semantics of this depends on the schema
251 * language.
252 * @param schemata the schema resources to load
253 */
254 public abstract Schema newSchema(Source[] schemata)
255 throws SAXException;
256
257 /**
258 * Creates a special schema.
259 * The exact semantics of this depends on the schema language.
260 */
261 public abstract Schema newSchema()
262 throws SAXException;
263
264 }