1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
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   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  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).
  16  *
  17  * You should have received a copy of the GNU General Public License version
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  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
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  23  * questions.
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  25 
  26 package javax.xml.bind;
  27 
  28 import org.w3c.dom.Node;
  29 
  30 import java.util.Collections;
  31 import java.util.Map;
  32 import java.util.Properties;
  33 import java.io.IOException;
  34 import java.io.InputStream;
  35 
  36 /**
  37  * The {@code JAXBContext} class provides the client's entry point to the
  38  * JAXB API. It provides an abstraction for managing the XML/Java binding
  39  * information necessary to implement the JAXB binding framework operations:
  40  * unmarshal, marshal and validate.
  41  *
  42  * <p>A client application normally obtains new instances of this class using
  43  * one of these two styles for newInstance methods, although there are other
  44  * specialized forms of the method available:
  45  *
  46  * <ul>
  47  * <li>{@link #newInstance(String, ClassLoader) JAXBContext.newInstance( "com.acme.foo:com.acme.bar" )} <br>
  48  * The JAXBContext instance is initialized from a list of colon
  49  * separated Java package names. Each java package contains
  50  * JAXB mapped classes, schema-derived classes and/or user annotated
  51  * classes. Additionally, the java package may contain JAXB package annotations
  52  * that must be processed. (see JLS, Section 7.4.1 "Named Packages").
  53  * </li>
  54  * <li>{@link #newInstance(Class...) JAXBContext.newInstance( com.acme.foo.Foo.class )} <br>
  55  * The JAXBContext instance is initialized with class(es)
  56  * passed as parameter(s) and classes that are statically reachable from
  57  * these class(es). See {@link #newInstance(Class...)} for details.
  58  * </li>
  59  * </ul>
  60  *
  61  * <p><i>
  62  * The following JAXB 1.0 requirement is only required for schema to
  63  * java interface/implementation binding. It does not apply to JAXB annotated
  64  * classes. JAXB Providers must generate a {@code jaxb.properties} file in
  65  * each package containing schema derived classes.  The property file must
  66  * contain a property named {@code javax.xml.bind.context.factory} whose
  67  * value is the name of the class that implements the {@code createContext}
  68  * APIs.</i>
  69  *
  70  * <p><i>
  71  * The class supplied by the provider does not have to be assignable to
  72  * {@code javax.xml.bind.JAXBContext}, it simply has to provide a class that
  73  * implements the {@code createContext} APIs.</i>
  74  *
  75  * <p><i>
  76  * In addition, the provider must call the
  77  * {@link DatatypeConverter#setDatatypeConverter(DatatypeConverterInterface)
  78  * DatatypeConverter.setDatatypeConverter} api prior to any client
  79  * invocations of the marshal and unmarshal methods.  This is necessary to
  80  * configure the datatype converter that will be used during these operations.</i>
  81  *
  82  * <a name="Unmarshalling"></a>
  83  * <h3>Unmarshalling</h3>
  84  * <p>
  85  * The {@link Unmarshaller} class provides the client application the ability
  86  * to convert XML data into a tree of Java content objects.
  87  * The unmarshal method allows for
  88  * any global XML element declared in the schema to be unmarshalled as
  89  * the root of an instance document.
  90  * Additionally, the unmarshal method allows for an unrecognized root element that
  91  * has  an xsi:type attribute's value that references a type definition declared in
  92  * the schema  to be unmarshalled as the root of an instance document.
  93  * The {@code JAXBContext} object
  94  * allows the merging of global elements and type definitions across a set of schemas (listed
  95  * in the {@code contextPath}). Since each schema in the schema set can belong
  96  * to distinct namespaces, the unification of schemas to an unmarshalling
  97  * context must be namespace independent.  This means that a client
  98  * application is able to unmarshal XML documents that are instances of
  99  * any of the schemas listed in the {@code contextPath}.  For example:
 100  *
 101  * <pre>
 102  *      JAXBContext jc = JAXBContext.newInstance( "com.acme.foo:com.acme.bar" );
 103  *      Unmarshaller u = jc.createUnmarshaller();
 104  *      FooObject fooObj = (FooObject)u.unmarshal( new File( "foo.xml" ) ); // ok
 105  *      BarObject barObj = (BarObject)u.unmarshal( new File( "bar.xml" ) ); // ok
 106  *      BazObject bazObj = (BazObject)u.unmarshal( new File( "baz.xml" ) ); // error, "com.acme.baz" not in contextPath
 107  * </pre>
 108  *
 109  * <p>
 110  * The client application may also generate Java content trees explicitly rather
 111  * than unmarshalling existing XML data.  For all JAXB-annotated value classes,
 112  * an application can create content using constructors.
 113  * For schema-derived interface/implementation classes and for the
 114  * creation of elements that are not bound to a JAXB-annotated
 115  * class, an application needs to have access and knowledge about each of
 116  * the schema derived {@code ObjectFactory} classes that exist in each of
 117  * java packages contained in the {@code contextPath}.  For each schema
 118  * derived java class, there is a static factory method that produces objects
 119  * of that type.  For example,
 120  * assume that after compiling a schema, you have a package {@code com.acme.foo}
 121  * that contains a schema derived interface named {@code PurchaseOrder}.  In
 122  * order to create objects of that type, the client application would use the
 123  * factory method like this:
 124  *
 125  * <pre>
 126  *       com.acme.foo.PurchaseOrder po =
 127  *           com.acme.foo.ObjectFactory.createPurchaseOrder();
 128  * </pre>
 129  *
 130  * <p>
 131  * Once the client application has an instance of the the schema derived object,
 132  * it can use the mutator methods to set content on it.
 133  *
 134  * <p>
 135  * For more information on the generated {@code ObjectFactory} classes, see
 136  * Section 4.2 <i>Java Package</i> of the specification.
 137  *
 138  * <p>
 139  * <i>The provider must generate a class in each
 140  * package that contains all of the necessary object factory methods for that
 141  * package named ObjectFactory as well as the static
 142  * {@code newInstance( javaContentInterface )} method</i>
 143  *
 144  * <h3>Marshalling</h3>
 145  * <p>
 146  * The {@link Marshaller} class provides the client application the ability
 147  * to convert a Java content tree back into XML data.  There is no difference
 148  * between marshalling a content tree that is created manually using the factory
 149  * methods and marshalling a content tree that is the result an {@code unmarshal}
 150  * operation.  Clients can marshal a java content tree back to XML data
 151  * to a {@code java.io.OutputStream} or a {@code java.io.Writer}.  The
 152  * marshalling process can alternatively produce SAX2 event streams to a
 153  * registered {@code ContentHandler} or produce a DOM Node object.
 154  * Client applications have control over the output encoding as well as
 155  * whether or not to marshal the XML data as a complete document or
 156  * as a fragment.
 157  *
 158  * <p>
 159  * Here is a simple example that unmarshals an XML document and then marshals
 160  * it back out:
 161  *
 162  * <pre>
 163  *        JAXBContext jc = JAXBContext.newInstance( "com.acme.foo" );
 164  *
 165  *        // unmarshal from foo.xml
 166  *        Unmarshaller u = jc.createUnmarshaller();
 167  *        FooObject fooObj = (FooObject)u.unmarshal( new File( "foo.xml" ) );
 168  *
 169  *        // marshal to System.out
 170  *        Marshaller m = jc.createMarshaller();
 171  *        m.marshal( fooObj, System.out );
 172  * </pre>
 173  *
 174  *
 175  * <h3>Validation</h3>
 176  * <p>
 177  * Validation has been changed significantly since JAXB 1.0.  The {@link Validator}
 178  * class has been deprecated and made optional.  This means that you are advised
 179  * not to use this class and, in fact, it may not even be available depending on
 180  * your JAXB provider.  JAXB 1.0 client applications that rely on {@code Validator}
 181  * will still work properly when deployed with the JAXB 1.0 runtime system.
 182  *
 183  * In JAXB 2.0, the {@link Unmarshaller} has included convenince methods that expose
 184  * the JAXP 1.3 {@link javax.xml.validation} framework.  Please refer to the
 185  * {@link Unmarshaller#setSchema(javax.xml.validation.Schema)} API for more
 186  * information.
 187  *
 188  *
 189  * <h3>JAXB Runtime Binding Framework Compatibility</h3>
 190  * <p>
 191  * The following JAXB 1.0 restriction only applies to binding schema to
 192  * interfaces/implementation classes.
 193  * Since this binding does not require a common runtime system, a JAXB
 194  * client application must not attempt to mix runtime objects ({@code JAXBContext,
 195  * Marshaller}, etc. ) from different providers.  This does not
 196  * mean that the client application isn't portable, it simply means that a
 197  * client has to use a runtime system provided by the same provider that was
 198  * used to compile the schema.
 199  *
 200  *
 201  * <h3>Discovery of JAXB implementation</h3>
 202  * <p>
 203  * To create an instance of {@link JAXBContext}, one of {@code JAXBContext.newInstance(...)} methods is invoked. After
 204  * JAX-B implementation is discovered, call is delegated to appropriate provider's method {@code createContext(...)}
 205  * passing parameters from the original call.
 206  * <p>
 207  * JAX-B implementation discovery happens each time {@code JAXBContext.newInstance} is invoked. If there is no user
 208  * specific configuration provided, default JAX-B provider must be returned.
 209  * <p>
 210  * Implementation discovery consists of following steps:
 211  *
 212  * <ol>
 213  *
 214  * <li>
 215  * Packages/classes explicitly passed in to the {@link #newInstance} method are processed in the order they are
 216  * specified, until {@code jaxb.properties} file is looked up in its package, by using the associated classloader &mdash;
 217  * this is {@link Class#getClassLoader() the owner class loader} for a {@link Class} argument, and for a package
 218  * the specified {@link ClassLoader}.
 219  *
 220  * <p>
 221  * If such a resource is discovered, it is {@link Properties#load(InputStream) loaded} as a property file, and
 222  * the value of the {@link #JAXB_CONTEXT_FACTORY} key will be assumed to be the provider factory class. If no value
 223  * found, {@code "javax.xml.bind.context.factory"} is used as a key for backwards compatibility reasons. This class is
 224  * then loaded by the associated class loader discussed above.
 225  *
 226  * <p>
 227  * This phase of the look up allows some packages to force the use of a certain JAXB implementation.
 228  * (For example, perhaps the schema compiler has generated some vendor extension in the code.)
 229  *
 230  * <li>
 231  * If the system property {@link #JAXB_CONTEXT_FACTORY} exists, then its value is assumed to be the provider
 232  * factory class. If no such property exists, properties {@code "javax.xml.bind.context.factory"} and
 233  * {@code "javax.xml.bind.JAXBContext"} are checked too (in this order), for backwards compatibility reasons. This phase
 234  * of the look up enables per-JVM override of the JAXB implementation.
 235  *
 236  * <li>
 237  * Provider of {@link javax.xml.bind.JAXBContextFactory} is loaded using the service-provider loading
 238  * facilities, defined by the {@link java.util.ServiceLoader} class, to attempt
 239  * to locate and load an implementation of the service using the {@linkplain
 240  * java.util.ServiceLoader#load(java.lang.Class) default loading mechanism}: the service-provider loading facility
 241  * will use the {@linkplain java.lang.Thread#getContextClassLoader() current thread's context class loader}
 242  * to attempt to load the context factory. If the context class loader is null, the
 243  * {@linkplain ClassLoader#getSystemClassLoader() system class loader} will be used.
 244  * <br>
 245  * In case of {@link java.util.ServiceConfigurationError service
 246  * configuration error} a {@link javax.xml.bind.JAXBException} will be thrown.
 247  *
 248  * <li>
 249  * Look for resource {@code /META-INF/services/javax.xml.bind.JAXBContext} using provided class loader.
 250  * Methods without class loader parameter use {@code Thread.currentThread().getContextClassLoader()}.
 251  * If such a resource exists, its content is assumed to be the provider factory class.
 252  *
 253  * This configuration method is deprecated.
 254  *
 255  * <li>
 256  * Finally, if all the steps above fail, then the rest of the look up is unspecified. That said,
 257  * the recommended behavior is to simply look for some hard-coded platform default JAXB implementation.
 258  * This phase of the look up is so that Java SE can have its own JAXB implementation as the last resort.
 259  * </ol>
 260  *
 261  * <p>
 262  * Once the provider factory class is discovered, context creation is delegated to one of its
 263  * {@code createContext(...)} methods.
 264  *
 265  * For backward compatibility reasons, there are two ways how to implement provider factory class:
 266  * <ol>
 267  *     <li>the class is implementation of {@link javax.xml.bind.JAXBContextFactory}. It must also implement no-arg
 268  *     constructor. If discovered in other step then 3, new instance using no-arg constructor is created first.
 269  *     After that, appropriate instance method is invoked on this instance.
 270  *     <li>the class is not implementation of interface above and then it is mandated to implement the following
 271  *     static method signatures:
 272  * <pre>
 273  *
 274  * public static JAXBContext createContext(
 275  *                                      String contextPath,
 276  *                                      ClassLoader classLoader,
 277  *                                      Map&lt;String,Object&gt; properties ) throws JAXBException
 278  *
 279  * public static JAXBContext createContext(
 280  *                                      Class[] classes,
 281  *                                      Map&lt;String,Object&gt; properties ) throws JAXBException
 282  * </pre>
 283  *      In this scenario, appropriate static method is used instead of instance method. This approach is incompatible
 284  *      with {@link java.util.ServiceLoader} so it can't be used with step 3.
 285  * </ol>
 286  * <p>
 287  * There is no difference in behavior of given method {@code createContext(...)} regardless of whether it uses approach
 288  * 1 (JAXBContextFactory) or 2 (no interface, static methods).
 289  *
 290  * @apiNote
 291  * Service discovery method using resource {@code /META-INF/services/javax.xml.bind.JAXBContext} (described in step 4)
 292  * is supported only to allow backwards compatibility, it is strongly recommended to migrate to standard
 293  * {@link java.util.ServiceLoader} mechanism (described in step 3). The difference here is the resource name, which
 294  * doesn't match service's type name.
 295  * <p>
 296  * Also using providers implementing interface {@link JAXBContextFactory} is preferred over using ones defining
 297  * static methods, same as {@link JAXBContext#JAXB_CONTEXT_FACTORY} property is preferred over property
 298  * {@code "javax.xml.bind.context.factory"}
 299  *
 300  * @implNote
 301  * Within the last step, if Glassfish AS environment detected, its specific service loader is used to find factory class.
 302  *
 303  * @author <ul><li>Ryan Shoemaker, Sun Microsystems, Inc.</li>
 304  *             <li>Kohsuke Kawaguchi, Sun Microsystems, Inc.</li>
 305  *             <li>Joe Fialli, Sun Microsystems, Inc.</li></ul>
 306  *
 307  * @see Marshaller
 308  * @see Unmarshaller
 309  * @see <a href="http://docs.oracle.com/javase/specs/jls/se7/html/jls-7.html#jls-7.4.1">S 7.4.1 "Named Packages"
 310  *      in Java Language Specification</a>
 311  *
 312  * @since 1.6, JAXB 1.0
 313  */
 314 public abstract class JAXBContext {
 315 
 316     /**
 317      * The name of the property that contains the name of the class capable
 318      * of creating new {@code JAXBContext} objects.
 319      */
 320     public static final String JAXB_CONTEXT_FACTORY = "javax.xml.bind.JAXBContextFactory";
 321 
 322     protected JAXBContext() {
 323     }
 324 
 325 
 326     /**
 327      * Create a new instance of a {@code JAXBContext} class.
 328      *
 329      * <p>
 330      * This is a convenience method to invoke the
 331      * {@link #newInstance(String,ClassLoader)} method with
 332      * the context class loader of the current thread.
 333      *
 334      * @throws JAXBException if an error was encountered while creating the
 335      *               {@code JAXBContext}. See {@link JAXBContext#newInstance(String, ClassLoader, Map)} for details.
 336      */
 337     public static JAXBContext newInstance( String contextPath )
 338             throws JAXBException {
 339 
 340         //return newInstance( contextPath, JAXBContext.class.getClassLoader() );
 341         return newInstance( contextPath, getContextClassLoader());
 342     }
 343 
 344     /**
 345      * Create a new instance of a {@code JAXBContext} class.
 346      *
 347      * <p>
 348      * The client application must supply a context path which is a list of
 349      * colon (':', \u005Cu003A) separated java package names that contain
 350      * schema-derived classes and/or fully qualified JAXB-annotated classes.
 351      * Schema-derived
 352      * code is registered with the JAXBContext by the
 353      * ObjectFactory.class generated per package.
 354      * Alternatively than being listed in the context path, programmer
 355      * annotated JAXB mapped classes can be listed in a
 356      * {@code jaxb.index} resource file, format described below.
 357      * Note that a java package can contain both schema-derived classes and
 358      * user annotated JAXB classes. Additionally, the java package may
 359      * contain JAXB package annotations  that must be processed. (see JLS,
 360      * Section 7.4.1 "Named Packages").
 361      * </p>
 362      *
 363      * <p>
 364      * Every package listed on the contextPath must meet <b>one or both</b> of the
 365      * following conditions otherwise a {@code JAXBException} will be thrown:
 366      * </p>
 367      * <ol>
 368      *   <li>it must contain ObjectFactory.class</li>
 369      *   <li>it must contain jaxb.index</li>
 370      * </ol>
 371      *
 372      * <p>
 373      * <b>Format for jaxb.index</b>
 374      * <p>
 375      * The file contains a newline-separated list of class names.
 376      * Space and tab characters, as well as blank
 377      * lines, are ignored. The comment character
 378      * is '#' (0x23); on each line all characters following the first comment
 379      * character are ignored. The file must be encoded in UTF-8. Classes that
 380      * are reachable, as defined in {@link #newInstance(Class...)}, from the
 381      * listed classes are also registered with JAXBContext.
 382      * <p>
 383      * Constraints on class name occuring in a {@code jaxb.index} file are:
 384      * <ul>
 385      *   <li>Must not end with ".class".</li>
 386      *   <li>Class names are resolved relative to package containing
 387      *       {@code jaxb.index} file. Only classes occuring directly in package
 388      *       containing {@code jaxb.index} file are allowed.</li>
 389      *   <li>Fully qualified class names are not allowed.
 390      *       A qualified class name,relative to current package,
 391      *       is only allowed to specify a nested or inner class.</li>
 392      * </ul>
 393      *
 394      * <p>
 395      * To maintain compatibility with JAXB 1.0 schema to java
 396      * interface/implementation binding, enabled by schema customization
 397      * {@code <jaxb:globalBindings valueClass="false">},
 398      * the JAXB provider will ensure that each package on the context path
 399      * has a {@code jaxb.properties} file which contains a value for the
 400      * {@code javax.xml.bind.context.factory} property and that all values
 401      * resolve to the same provider.  This requirement does not apply to
 402      * JAXB annotated classes.
 403      *
 404      * <p>
 405      * If there are any global XML element name collisions across the various
 406      * packages listed on the {@code contextPath}, a {@code JAXBException}
 407      * will be thrown.
 408      *
 409      * <p>
 410      * Mixing generated interface/impl bindings from multiple JAXB Providers
 411      * in the same context path may result in a {@code JAXBException}
 412      * being thrown.
 413      *
 414      * <p>
 415      * The steps involved in discovering the JAXB implementation is discussed in the class javadoc.
 416      *
 417      * @param contextPath list of java package names that contain schema
 418      *                    derived class and/or java to schema (JAXB-annotated)
 419      *                    mapped classes
 420      * @param classLoader
 421      *      This class loader will be used to locate the implementation
 422      *      classes.
 423      *
 424      * @return a new instance of a {@code JAXBContext}
 425      * @throws JAXBException if an error was encountered while creating the
 426      *               {@code JAXBContext}. See {@link JAXBContext#newInstance(String, ClassLoader, Map)} for details.
 427      */
 428     public static JAXBContext newInstance( String contextPath, ClassLoader classLoader ) throws JAXBException {
 429 
 430         return newInstance(contextPath,classLoader,Collections.<String,Object>emptyMap());
 431     }
 432 
 433     /**
 434      * Create a new instance of a {@code JAXBContext} class.
 435      *
 436      * <p>
 437      * This is mostly the same as {@link JAXBContext#newInstance(String, ClassLoader)},
 438      * but this version allows you to pass in provider-specific properties to configure
 439      * the instantiation of {@link JAXBContext}.
 440      *
 441      * <p>
 442      * The interpretation of properties is up to implementations. Implementations must
 443      * throw {@code JAXBException} if it finds properties that it doesn't understand.
 444      *
 445      * @param contextPath list of java package names that contain schema derived classes
 446      * @param classLoader
 447      *      This class loader will be used to locate the implementation classes.
 448      * @param properties
 449      *      provider-specific properties. Can be null, which means the same thing as passing
 450      *      in an empty map.
 451      *
 452      * @return a new instance of a {@code JAXBContext}
 453      * @throws JAXBException if an error was encountered while creating the
 454      *                       {@code JAXBContext} such as
 455      * <ol>
 456      *   <li>failure to locate either ObjectFactory.class or jaxb.index in the packages</li>
 457      *   <li>an ambiguity among global elements contained in the contextPath</li>
 458      *   <li>failure to locate a value for the context factory provider property</li>
 459      *   <li>mixing schema derived packages from different providers on the same contextPath</li>
 460      * </ol>
 461      * @since 1.6, JAXB 2.0
 462      */
 463     public static JAXBContext newInstance( String contextPath,
 464                                            ClassLoader classLoader,
 465                                            Map<String,?>  properties  ) throws JAXBException {
 466 
 467         return ContextFinder.find(
 468                         /* The default property name according to the JAXB spec */
 469                 JAXB_CONTEXT_FACTORY,
 470 
 471                         /* the context path supplied by the client app */
 472                 contextPath,
 473 
 474                         /* class loader to be used */
 475                 classLoader,
 476                 properties );
 477     }
 478 
 479 // TODO: resurrect this once we introduce external annotations
 480 //    /**
 481 //     * Create a new instance of a {@code JAXBContext} class.
 482 //     *
 483 //     * <p>
 484 //     * The client application must supply a list of classes that the new
 485 //     * context object needs to recognize.
 486 //     *
 487 //     * Not only the new context will recognize all the classes specified,
 488 //     * but it will also recognize any classes that are directly/indirectly
 489 //     * referenced statically from the specified classes.
 490 //     *
 491 //     * For example, in the following Java code, if you do
 492 //     * {@code newInstance(Foo.class)}, the newly created {@link JAXBContext}
 493 //     * will recognize both {@code Foo} and {@code Bar}, but not {@code Zot}:
 494 //     * <pre>
 495 //     * class Foo {
 496 //     *      Bar b;
 497 //     * }
 498 //     * class Bar { int x; }
 499 //     * class Zot extends Bar { int y; }
 500 //     * </pre>
 501 //     *
 502 //     * Therefore, a typical client application only needs to specify the
 503 //     * top-level classes, but it needs to be careful.
 504 //     *
 505 //     * TODO: if we are to define other mechanisms, refer to them.
 506 //     *
 507 //     * @param externalBindings
 508 //     *      list of external binding files. Can be null or empty if none is used.
 509 //     *      when specified, those files determine how the classes are bound.
 510 //     *
 511 //     * @param classesToBeBound
 512 //     *      list of java classes to be recognized by the new {@link JAXBContext}.
 513 //     *      Can be empty, in which case a {@link JAXBContext} that only knows about
 514 //     *      spec-defined classes will be returned.
 515 //     *
 516 //     * @return
 517 //     *      A new instance of a {@code JAXBContext}.
 518 //     *
 519 //     * @throws JAXBException
 520 //     *      if an error was encountered while creating the
 521 //     *      {@code JAXBContext}, such as (but not limited to):
 522 //     * <ol>
 523 //     *  <li>No JAXB implementation was discovered
 524 //     *  <li>Classes use JAXB annotations incorrectly
 525 //     *  <li>Classes have colliding annotations (i.e., two classes with the same type name)
 526 //     *  <li>Specified external bindings are incorrect
 527 //     *  <li>The JAXB implementation was unable to locate
 528 //     *      provider-specific out-of-band information (such as additional
 529 //     *      files generated at the development time.)
 530 //     * </ol>
 531 //     *
 532 //     * @throws IllegalArgumentException
 533 //     *      if the parameter contains {@code null} (i.e., {@code newInstance(null);})
 534 //     *
 535 //     * @since JAXB 2.0
 536 //     */
 537 //    public static JAXBContext newInstance( Source[] externalBindings, Class... classesToBeBound )
 538 //        throws JAXBException {
 539 //
 540 //        // empty class list is not an error, because the context will still include
 541 //        // spec-specified classes like String and Integer.
 542 //        // if(classesToBeBound.length==0)
 543 //        //    throw new IllegalArgumentException();
 544 //
 545 //        // but it is an error to have nulls in it.
 546 //        for( int i=classesToBeBound.length-1; i>=0; i-- )
 547 //            if(classesToBeBound[i]==null)
 548 //                throw new IllegalArgumentException();
 549 //
 550 //        return ContextFinder.find(externalBindings,classesToBeBound);
 551 //    }
 552 
 553     /**
 554      * Create a new instance of a {@code JAXBContext} class.
 555      *
 556      * <p>
 557      * The client application must supply a list of classes that the new
 558      * context object needs to recognize.
 559      *
 560      * Not only the new context will recognize all the classes specified,
 561      * but it will also recognize any classes that are directly/indirectly
 562      * referenced statically from the specified classes. Subclasses of
 563      * referenced classes nor {@code @XmlTransient} referenced classes
 564      * are not registered with JAXBContext.
 565      *
 566      * For example, in the following Java code, if you do
 567      * {@code newInstance(Foo.class)}, the newly created {@link JAXBContext}
 568      * will recognize both {@code Foo} and {@code Bar}, but not {@code Zot} or {@code FooBar}:
 569      * <pre>
 570      * class Foo {
 571      *      @XmlTransient FooBar c;
 572      *      Bar b;
 573      * }
 574      * class Bar { int x; }
 575      * class Zot extends Bar { int y; }
 576      * class FooBar { }
 577      * </pre>
 578      *
 579      * Therefore, a typical client application only needs to specify the
 580      * top-level classes, but it needs to be careful.
 581      *
 582      * <p>
 583      * Note that for each java package registered with JAXBContext,
 584      * when the optional package annotations exist, they must be processed.
 585      * (see JLS, Section 7.4.1 "Named Packages").
 586      *
 587      * <p>
 588      * The steps involved in discovering the JAXB implementation is discussed in the class javadoc.
 589      *
 590      * @param classesToBeBound
 591      *      list of java classes to be recognized by the new {@link JAXBContext}.
 592      *      Can be empty, in which case a {@link JAXBContext} that only knows about
 593      *      spec-defined classes will be returned.
 594      *
 595      * @return
 596      *      A new instance of a {@code JAXBContext}.
 597      *
 598      * @throws JAXBException if an error was encountered while creating the
 599      *               {@code JAXBContext}. See {@link JAXBContext#newInstance(Class[], Map)} for details.
 600      *
 601      * @throws IllegalArgumentException
 602      *      if the parameter contains {@code null} (i.e., {@code newInstance(null);})
 603      *
 604      * @since 1.6, JAXB 2.0
 605      */
 606     public static JAXBContext newInstance( Class<?> ... classesToBeBound )
 607             throws JAXBException {
 608 
 609         return newInstance(classesToBeBound,Collections.<String,Object>emptyMap());
 610     }
 611 
 612     /**
 613      * Create a new instance of a {@code JAXBContext} class.
 614      *
 615      * <p>
 616      * An overloading of {@link JAXBContext#newInstance(Class...)}
 617      * to configure 'properties' for this instantiation of {@link JAXBContext}.
 618      *
 619      * <p>
 620      * The interpretation of properties is up to implementations. Implementations must
 621      * throw {@code JAXBException} if it finds properties that it doesn't understand.
 622      *
 623      * @param classesToBeBound
 624      *      list of java classes to be recognized by the new {@link JAXBContext}.
 625      *      Can be empty, in which case a {@link JAXBContext} that only knows about
 626      *      spec-defined classes will be returned.
 627      * @param properties
 628      *      provider-specific properties. Can be null, which means the same thing as passing
 629      *      in an empty map.
 630      *
 631      * @return
 632      *      A new instance of a {@code JAXBContext}.
 633      *
 634      * @throws JAXBException
 635      *      if an error was encountered while creating the
 636      *      {@code JAXBContext}, such as (but not limited to):
 637      * <ol>
 638      *  <li>No JAXB implementation was discovered
 639      *  <li>Classes use JAXB annotations incorrectly
 640      *  <li>Classes have colliding annotations (i.e., two classes with the same type name)
 641      *  <li>The JAXB implementation was unable to locate
 642      *      provider-specific out-of-band information (such as additional
 643      *      files generated at the development time.)
 644      * </ol>
 645      *
 646      * @throws IllegalArgumentException
 647      *      if the parameter contains {@code null} (i.e., {@code newInstance(null,someMap);})
 648      *
 649      * @since 1.6, JAXB 2.0
 650      */
 651     public static JAXBContext newInstance( Class<?>[] classesToBeBound, Map<String,?> properties )
 652             throws JAXBException {
 653 
 654         if (classesToBeBound == null) {
 655             throw new IllegalArgumentException();
 656         }
 657 
 658         // but it is an error to have nulls in it.
 659         for (int i = classesToBeBound.length - 1; i >= 0; i--) {
 660             if (classesToBeBound[i] == null) {
 661                 throw new IllegalArgumentException();
 662             }
 663         }
 664 
 665         return ContextFinder.find(classesToBeBound,properties);
 666     }
 667 
 668     /**
 669      * Create an {@code Unmarshaller} object that can be used to convert XML
 670      * data into a java content tree.
 671      *
 672      * @return an {@code Unmarshaller} object
 673      *
 674      * @throws JAXBException if an error was encountered while creating the
 675      *                       {@code Unmarshaller} object
 676      */
 677     public abstract Unmarshaller createUnmarshaller() throws JAXBException;
 678 
 679 
 680     /**
 681      * Create a {@code Marshaller} object that can be used to convert a
 682      * java content tree into XML data.
 683      *
 684      * @return a {@code Marshaller} object
 685      *
 686      * @throws JAXBException if an error was encountered while creating the
 687      *                       {@code Marshaller} object
 688      */
 689     public abstract Marshaller createMarshaller() throws JAXBException;
 690 
 691 
 692     /**
 693      * {@link Validator} has been made optional and deprecated in JAXB 2.0.  Please
 694      * refer to the javadoc for {@link Validator} for more detail.
 695      * <p>
 696      * Create a {@code Validator} object that can be used to validate a
 697      * java content tree against its source schema.
 698      *
 699      * @return a {@code Validator} object
 700      *
 701      * @throws JAXBException if an error was encountered while creating the
 702      *                       {@code Validator} object
 703      * @deprecated since JAXB2.0
 704      */
 705     public abstract Validator createValidator() throws JAXBException;
 706 
 707     /**
 708      * Creates a {@code Binder} object that can be used for
 709      * associative/in-place unmarshalling/marshalling.
 710      *
 711      * @param domType select the DOM API to use by passing in its DOM Node class.
 712      *
 713      * @return always a new valid {@code Binder} object.
 714      *
 715      * @throws UnsupportedOperationException
 716      *      if DOM API corresponding to {@code domType} is not supported by
 717      *      the implementation.
 718      *
 719      * @since 1.6, JAXB 2.0
 720      */
 721     public <T> Binder<T> createBinder(Class<T> domType) {
 722         // to make JAXB 1.0 implementations work, this method must not be
 723         // abstract
 724         throw new UnsupportedOperationException();
 725     }
 726 
 727     /**
 728      * Creates a {@code Binder} for W3C DOM.
 729      *
 730      * @return always a new valid {@code Binder} object.
 731      *
 732      * @since 1.6, JAXB 2.0
 733      */
 734     public Binder<Node> createBinder() {
 735         return createBinder(Node.class);
 736     }
 737 
 738     /**
 739      * Creates a {@code JAXBIntrospector} object that can be used to
 740      * introspect JAXB objects.
 741      *
 742      * @return
 743      *      always return a non-null valid {@code JAXBIntrospector} object.
 744      *
 745      * @throws UnsupportedOperationException
 746      *      Calling this method on JAXB 1.0 implementations will throw
 747      *      an UnsupportedOperationException.
 748      *
 749      * @since 1.6, JAXB 2.0
 750      */
 751     public JAXBIntrospector createJAXBIntrospector() {
 752         // to make JAXB 1.0 implementations work, this method must not be
 753         // abstract
 754         throw new UnsupportedOperationException();
 755     }
 756 
 757     /**
 758      * Generates the schema documents for this context.
 759      *
 760      * @param outputResolver
 761      *      this object controls the output to which schemas
 762      *      will be sent.
 763      *
 764      * @throws IOException
 765      *      if {@link SchemaOutputResolver} throws an {@link IOException}.
 766      *
 767      * @throws UnsupportedOperationException
 768      *      Calling this method on JAXB 1.0 implementations will throw
 769      *      an UnsupportedOperationException.
 770      *
 771      * @since 1.6, JAXB 2.0
 772      */
 773     public void generateSchema(SchemaOutputResolver outputResolver) throws IOException  {
 774         // to make JAXB 1.0 implementations work, this method must not be
 775         // abstract
 776         throw new UnsupportedOperationException();
 777     }
 778 
 779     private static ClassLoader getContextClassLoader() {
 780         if (System.getSecurityManager() == null) {
 781             return Thread.currentThread().getContextClassLoader();
 782         } else {
 783             return java.security.AccessController.doPrivileged(
 784                     new java.security.PrivilegedAction<ClassLoader>() {
 785                         public ClassLoader run() {
 786                             return Thread.currentThread().getContextClassLoader();
 787                         }
 788                     });
 789         }
 790     }
 791 
 792 }