1 /*
2 * Copyright (c) 2009 The JOMC Project
3 * Copyright (c) 2005 Christian Schulte <cs@jomc.org>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * o Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 *
13 * o Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
16 * distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE JOMC PROJECT AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
20 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE JOMC PROJECT OR
22 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
23 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
24 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
25 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
26 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
27 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
28 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 *
30 * $Id: BootstrapContext.java 1393 2010-01-27 18:34:30Z schulte2005 $
31 *
32 */
33 package org.jomc.model.bootstrap;
34
35 import java.io.BufferedReader;
36 import java.io.File;
37 import java.io.FileInputStream;
38 import java.io.IOException;
39 import java.io.InputStream;
40 import java.io.InputStreamReader;
41 import java.lang.reflect.Constructor;
42 import java.lang.reflect.InvocationTargetException;
43 import java.net.URL;
44 import java.util.Collection;
45 import java.util.Comparator;
46 import java.util.Enumeration;
47 import java.util.Map;
48 import java.util.TreeMap;
49 import javax.xml.bind.JAXBContext;
50 import javax.xml.bind.JAXBException;
51 import javax.xml.bind.Marshaller;
52 import javax.xml.bind.Unmarshaller;
53 import javax.xml.bind.util.JAXBSource;
54 import javax.xml.validation.Validator;
55 import org.xml.sax.SAXException;
56
57 /**
58 * Object management and configuration model bootstrap context interface.
59 *
60 * @author <a href="mailto:cs@jomc.org">Christian Schulte</a>
61 * @version $Id: BootstrapContext.java 1393 2010-01-27 18:34:30Z schulte2005 $
62 * @see #createBootstrapContext(java.lang.ClassLoader)
63 */
64 public abstract class BootstrapContext
65 {
66
67 /** Class name of the {@code BootstrapContext} implementation. */
68 private static volatile String bootstrapContextClassName;
69
70 /** The class loader of the context. */
71 private ClassLoader classLoader;
72
73 /**
74 * Creates a new {@code BootstrapContext} instance taking a class loader.
75 *
76 * @param classLoader The class loader of the context.
77 */
78 public BootstrapContext( final ClassLoader classLoader )
79 {
80 super();
81 this.classLoader = classLoader;
82 }
83
84 /**
85 * Gets the class loader of the context.
86 *
87 * @return The class loader of the context.
88 */
89 public ClassLoader getClassLoader()
90 {
91 if ( this.classLoader == null )
92 {
93 this.classLoader = new ClassLoader( null )
94 {
95
96 @Override
97 public String toString()
98 {
99 return BootstrapContext.class.getName() + ".BootstrapClassLoader@" +
100 System.identityHashCode( this );
101
102 }
103
104 };
105
106 }
107
108 return this.classLoader;
109 }
110
111 /**
112 * Gets the name of the class providing the {@code BootstrapContext} implementation.
113 * <p>The name of the class providing the {@code BootstrapContext} implementation returned by method
114 * {@link #createBootstrapContext(java.lang.ClassLoader)} is controlled by system property
115 * {@code org.jomc.model.bootstrap.BootstrapContext.className}. If that property is not set, the name of the
116 * {@link DefaultBootstrapContext} class is returned.</p>
117 *
118 * @return The name of the class providing the {@code BootstrapContext} implementation.
119 *
120 * @see #setBootstrapContextClassName(java.lang.String)
121 */
122 public static String getBootstrapContextClassName()
123 {
124 if ( bootstrapContextClassName == null )
125 {
126 bootstrapContextClassName = System.getProperty( "org.jomc.model.bootstrap.BootstrapContext.className",
127 DefaultBootstrapContext.class.getName() );
128
129 }
130
131 return bootstrapContextClassName;
132 }
133
134 /**
135 * Sets the name of the class providing the {@code BootstrapContext} implementation.
136 *
137 * @param value The new name of the class providing the {@code BootstrapContext} implementation or {@code null}.
138 *
139 * @see #getBootstrapContextClassName()
140 */
141 public static void setBootstrapContextClassName( final String value )
142 {
143 bootstrapContextClassName = value;
144 }
145
146 /**
147 * Searches the context for a class with a given name.
148 *
149 * @param name The name of the class to return.
150 *
151 * @return A Class object of the class with name {@code name} or {@code null} if no such class is found.
152 *
153 * @throws NullPointerException if {@code name} is {@code null}.
154 * @throws BootstrapException if searching fails.
155 */
156 public Class findClass( final String name ) throws BootstrapException
157 {
158 if ( name == null )
159 {
160 throw new NullPointerException( "name" );
161 }
162
163 try
164 {
165 return Class.forName( name, true, this.getClassLoader() );
166 }
167 catch ( final ClassNotFoundException e )
168 {
169 return null;
170 }
171 }
172
173 /**
174 * Searches the context for a resource with a given name.
175 *
176 * @param name The name of the resource to return.
177 *
178 * @return An URL object for reading the resource or {@code null} if no such resource is found.
179 *
180 * @throws NullPointerException if {@code name} is {@code null}.
181 * @throws BootstrapException if searching fails.
182 */
183 public URL findResource( final String name ) throws BootstrapException
184 {
185 if ( name == null )
186 {
187 throw new NullPointerException( "name" );
188 }
189
190 return this.getClassLoader().getResource( name );
191 }
192
193 /**
194 * Searches the context for resources with a given name.
195 *
196 * @param name The name of the resources to return.
197 *
198 * @return An enumeration of URL objects for reading the resources. If no resources are found, the enumeration will
199 * be empty.
200 *
201 * @throws NullPointerException if {@code name} is {@code null}.
202 * @throws BootstrapException if searching fails.
203 */
204 public Enumeration<URL> findResources( final String name ) throws BootstrapException
205 {
206 if ( name == null )
207 {
208 throw new NullPointerException( "name" );
209 }
210
211 try
212 {
213 return this.getClassLoader().getResources( name );
214 }
215 catch ( final IOException e )
216 {
217 throw new BootstrapException( e );
218 }
219 }
220
221 /**
222 * Searches the context for schemas.
223 * <p>This method loads {@code SchemaProvider} classes setup via
224 * {@code META-INF/services/org.jomc.model.bootstrap.SchemaProvider} resources and returns a list of provided
225 * schemas.</p>
226 *
227 * @return The schemas found in the context.
228 *
229 * @throws BootstrapException if searching schemas fails.
230 *
231 * @see SchemaProvider#findSchemas(org.jomc.model.bootstrap.BootstrapContext)
232 */
233 public Schemas findSchemas() throws BootstrapException
234 {
235 try
236 {
237 final Schemas schemas = new Schemas();
238
239 final Collection<Class<SchemaProvider>> providers = this.loadProviders( SchemaProvider.class );
240 for ( Class<SchemaProvider> provider : providers )
241 {
242 final SchemaProvider schemaProvider = provider.newInstance();
243 final Schemas provided = schemaProvider.findSchemas( this );
244 if ( provided != null )
245 {
246 schemas.getSchema().addAll( provided.getSchema() );
247 }
248 }
249
250 final javax.xml.validation.Schema bootstrapSchema = this.createSchema();
251 final Validator validator = bootstrapSchema.newValidator();
252 validator.validate( new JAXBSource( this.createContext(), new ObjectFactory().createSchemas( schemas ) ) );
253
254 return schemas;
255 }
256 catch ( final InstantiationException e )
257 {
258 throw new BootstrapException( e );
259 }
260 catch ( final IllegalAccessException e )
261 {
262 throw new BootstrapException( e );
263 }
264 catch ( final JAXBException e )
265 {
266 throw new BootstrapException( e );
267 }
268 catch ( final SAXException e )
269 {
270 throw new BootstrapException( e );
271 }
272 catch ( final IOException e )
273 {
274 throw new BootstrapException( e );
275 }
276 }
277
278 /**
279 * Searches the context for services.
280 * <p>This method loads {@code ServiceProvider} classes setup via
281 * {@code META-INF/services/org.jomc.model.bootstrap.ServiceProvider} resources and returns a list of provided
282 * services.</p>
283 *
284 * @return The services found in the context.
285 *
286 * @throws BootstrapException if searching services fails.
287 *
288 * @see ServiceProvider#findServices(org.jomc.model.bootstrap.BootstrapContext)
289 */
290 public Services findServices() throws BootstrapException
291 {
292 try
293 {
294 final Services services = new Services();
295
296 final Collection<Class<ServiceProvider>> providers = this.loadProviders( ServiceProvider.class );
297 for ( Class<ServiceProvider> provider : providers )
298 {
299 final ServiceProvider serviceProvider = provider.newInstance();
300 final Services provided = serviceProvider.findServices( this );
301 if ( provided != null )
302 {
303 services.getService().addAll( provided.getService() );
304 }
305 }
306
307 final javax.xml.validation.Schema bootstrapSchema = this.createSchema();
308 final Validator validator = bootstrapSchema.newValidator();
309 validator.validate( new JAXBSource( this.createContext(), new ObjectFactory().createServices( services ) ) );
310
311 return services;
312 }
313 catch ( final InstantiationException e )
314 {
315 throw new BootstrapException( e );
316 }
317 catch ( final IllegalAccessException e )
318 {
319 throw new BootstrapException( e );
320 }
321 catch ( final JAXBException e )
322 {
323 throw new BootstrapException( e );
324 }
325 catch ( final SAXException e )
326 {
327 throw new BootstrapException( e );
328 }
329 catch ( final IOException e )
330 {
331 throw new BootstrapException( e );
332 }
333 }
334
335 /**
336 * Creates a new object management and configuration model {@code BootstrapContext} instance.
337 *
338 * @param classLoader The class loader to create a new object management and configuration model bootstrap context
339 * instance with or {@code null} to create a new bootstrap context using the platform's bootstrap class loader.
340 *
341 * @return A new {@code BootstrapContext} instance.
342 *
343 * @throws BootstrapException if creating a new object management and configuration model bootstrap context instance
344 * fails.
345 *
346 * @see #getBootstrapContextClassName()
347 */
348 public static BootstrapContext createBootstrapContext( final ClassLoader classLoader ) throws BootstrapException
349 {
350 if ( DefaultBootstrapContext.class.getName().equals( getBootstrapContextClassName() ) )
351 {
352 return new DefaultBootstrapContext( classLoader );
353 }
354
355 try
356 {
357 final Class clazz = Class.forName( getBootstrapContextClassName(), true, classLoader );
358 final Constructor ctor = clazz.getConstructor( ClassLoader.class );
359 return (BootstrapContext) ctor.newInstance( classLoader );
360 }
361 catch ( final ClassNotFoundException e )
362 {
363 throw new BootstrapException( e );
364 }
365 catch ( final NoSuchMethodException e )
366 {
367 throw new BootstrapException( e );
368 }
369 catch ( final InstantiationException e )
370 {
371 throw new BootstrapException( e );
372 }
373 catch ( final IllegalAccessException e )
374 {
375 throw new BootstrapException( e );
376 }
377 catch ( final InvocationTargetException e )
378 {
379 throw new BootstrapException( e );
380 }
381 catch ( final ClassCastException e )
382 {
383 throw new BootstrapException( e );
384 }
385 }
386
387 /**
388 * Creates a new object management and configuration model bootstrap JAXP schema instance.
389 *
390 * @return A new object management and configuration model bootstrap JAXP schema instance.
391 *
392 * @throws BootstrapException if creating a new object management and configuration model bootstrap JAXP schema
393 * instance fails.
394 */
395 public abstract javax.xml.validation.Schema createSchema() throws BootstrapException;
396
397 /**
398 * Creates a new object management and configuration model bootstrap JAXB context instance.
399 *
400 * @return A new object management and configuration model bootstrap JAXB context instance.
401 *
402 * @throws BootstrapException if creating a new object management and configuration model bootstrap JAXB context
403 * instance fails.
404 */
405 public abstract JAXBContext createContext() throws BootstrapException;
406
407 /**
408 * Creates a new object management and configuration model bootstrap JAXB marshaller instance.
409 *
410 * @return A new object management and configuration model bootstrap JAXB marshaller instance.
411 *
412 * @throws BootstrapException if creating a new object management and configuration model bootstrap JAXB marshaller
413 * instance fails.
414 */
415 public abstract Marshaller createMarshaller() throws BootstrapException;
416
417 /**
418 * Creates a new object management and configuration model bootstrap JAXB unmarshaller instance.
419 *
420 * @return A new object management and configuration model bootstrap JAXB unmarshaller instance.
421 *
422 * @throws BootstrapException if creating a new object management and configuration model bootstrap JAXB
423 * unmarshaller instance fails.
424 */
425 public abstract Unmarshaller createUnmarshaller() throws BootstrapException;
426
427 private <T> Collection<Class<T>> loadProviders( final Class<T> providerClass ) throws BootstrapException
428 {
429 try
430 {
431 final String providerNamePrefix = providerClass.getName() + ".";
432 final Map<String, Class<T>> providers = new TreeMap<String, Class<T>>( new Comparator<String>()
433 {
434
435 public int compare( final String key1, final String key2 )
436 {
437 return key1.compareTo( key2 );
438 }
439
440 } );
441
442 final File platformProviders = new File( new StringBuilder().append( System.getProperty( "java.home" ) ).
443 append( File.separator ).append( "jre" ).append( File.separator ).append( "lib" ).
444 append( File.separator ).append( "jomc.properties" ).toString() );
445
446 if ( platformProviders.exists() )
447 {
448 InputStream in = null;
449 final java.util.Properties p = new java.util.Properties();
450
451 try
452 {
453 in = new FileInputStream( platformProviders );
454 p.load( in );
455 }
456 finally
457 {
458 if ( in != null )
459 {
460 in.close();
461 }
462 }
463
464 for ( Map.Entry e : p.entrySet() )
465 {
466 if ( e.getKey().toString().startsWith( providerNamePrefix ) )
467 {
468 final Class<T> provider = this.findClass( e.getValue().toString() );
469 if ( provider != null )
470 {
471 providers.put( e.getKey().toString(), provider );
472 }
473 }
474 }
475 }
476
477 final Enumeration<URL> serviceProviders =
478 this.findResources( "META-INF/services/" + providerClass.getName() );
479
480 while ( serviceProviders.hasMoreElements() )
481 {
482 final URL url = serviceProviders.nextElement();
483 final BufferedReader reader = new BufferedReader( new InputStreamReader( url.openStream(), "UTF-8" ) );
484
485 String line = null;
486 while ( ( line = reader.readLine() ) != null )
487 {
488 if ( line.contains( "#" ) )
489 {
490 continue;
491 }
492
493 final Class<T> provider = this.findClass( line );
494 if ( provider != null )
495 {
496 providers.put( providerNamePrefix + providers.size(), provider );
497 }
498 }
499
500 reader.close();
501 }
502
503 return providers.values();
504 }
505 catch ( final IOException e )
506 {
507 throw new BootstrapException( e );
508 }
509 }
510
511 }