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package javax.xml.validation;
import java.io.File;
import java.net.URL;
import javax.xml.transform.Source;
import javax.xml.transform.stream.StreamSource;
import org.w3c.dom.ls.LSResourceResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.SAXException;
import org.xml.sax.SAXNotRecognizedException;
import org.xml.sax.SAXNotSupportedException;
import org.xml.sax.SAXParseException;
/**
* Factory that creates {@link Schema} objects. Entry-point to
* the validation API.
*
* <p>
* {@link SchemaFactory} is a schema compiler. It reads external
* representations of schemas and prepares them for validation.
*
* <p>
* The {@link SchemaFactory} class is not thread-safe. In other words,
* it is the application's responsibility to ensure that at most
* one thread is using a {@link SchemaFactory} object at any
* given moment. Implementations are encouraged to mark methods
* as <code>synchronized</code> to protect themselves from broken clients.
*
* <p>
* {@link SchemaFactory} is not re-entrant. While one of the
* <code>newSchema</code> methods is being invoked, applications
* may not attempt to recursively invoke the <code>newSchema</code> method,
* even from the same thread.
*
* <h2><a name="schemaLanguage"></a>Schema Language</h2>
* <p>
* This spec uses a namespace URI to designate a schema language.
* The following table shows the values defined by this specification.
* <p>
* To be compliant with the spec, the implementation
* is only required to support W3C XML Schema 1.0. However,
* if it chooses to support other schema languages listed here,
* it must conform to the relevant behaviors described in this spec.
*
* <p>
* Schema languages not listed here are expected to
* introduce their own URIs to represent themselves.
* The {@link SchemaFactory} class is capable of locating other
* implementations for other schema languages at run-time.
*
* <p>
* Note that because the XML DTD is strongly tied to the parsing process
* and has a significant effect on the parsing process, it is impossible
* to define the DTD validation as a process independent from parsing.
* For this reason, this specification does not define the semantics for
* the XML DTD. This doesn't prohibit implementors from implementing it
* in a way they see fit, but <em>users are warned that any DTD
* validation implemented on this interface necessarily deviate from
* the XML DTD semantics as defined in the XML 1.0</em>.
*
* <table border="1" cellpadding="2">
* <thead>
* <tr>
* <th>value</th>
* <th>language</th>
* </tr>
* </thead>
* <tbody>
* <tr>
* <td>{@link javax.xml.XMLConstants#W3C_XML_SCHEMA_NS_URI} ("<code>http://www.w3.org/2001/XMLSchema</code>")</td>
* <td><a href="http://www.w3.org/TR/xmlschema-1">W3C XML Schema 1.0</a></td>
* </tr>
* <tr>
* <td>{@link javax.xml.XMLConstants#RELAXNG_NS_URI} ("<code>http://relaxng.org/ns/structure/1.0</code>")</td>
* <td><a href="http://www.relaxng.org/">RELAX NG 1.0</a></td>
* </tr>
* </tbody>
* </table>
*
* @author <a href="mailto:Kohsuke.Kawaguchi@Sun.com">Kohsuke Kawaguchi</a>
* @author <a href="mailto:Neeraj.Bajaj@sun.com">Neeraj Bajaj</a>
*
* @since 1.5
*/
public abstract class SchemaFactory {
private static SecuritySupport ss = new SecuritySupport();
/**
* <p>Constructor for derived classes.</p>
*
* <p>The constructor does nothing.</p>
*
* <p>Derived classes must create {@link SchemaFactory} objects that have
* <code>null</code> {@link ErrorHandler} and
* <code>null</code> {@link LSResourceResolver}.</p>
*/
protected SchemaFactory() {
}
/**
* <p>Lookup an implementation of the <code>SchemaFactory</code> that supports the specified
* schema language and return it.</p>
*
* <p>To find a <code>SchemaFactory</code> object for a given schema language,
* this method looks the following places in the following order
* where "the class loader" refers to the context class loader:</p>
* <ol>
* <li>
* If the system property
* <code>"javax.xml.validation.SchemaFactory:<i>schemaLanguage</i>"</code>
* is present (where <i>schemaLanguage</i> is the parameter
* to this method), then its value is read
* as a class name. The method will try to
* create a new instance of this class by using the class loader,
* and returns it if it is successfully created.
* </li>
* <li>
* <code>$java.home/lib/jaxp.properties</code> is read and
* the value associated with the key being the system property above
* is looked for. If present, the value is processed just like above.
* </li>
* <li>
* Use the service-provider loading facilities, defined by the
* {@link java.util.ServiceLoader} class, to attempt to locate and load an
* implementation of the service using the {@linkplain
* java.util.ServiceLoader#load(java.lang.Class) default loading mechanism}:
* the service-provider loading facility will use the {@linkplain
* java.lang.Thread#getContextClassLoader() current thread's context class loader}
* to attempt to load the service. If the context class
* loader is null, the {@linkplain
* ClassLoader#getSystemClassLoader() system class loader} will be used.
* <br>
* Each potential service provider is required to implement the method
* {@link #isSchemaLanguageSupported(String schemaLanguage)}.
* <br>
* The first service provider found that supports the specified schema
* language is returned.
* <br>
* In case of {@link java.util.ServiceConfigurationError} a
* {@link SchemaFactoryConfigurationError} will be thrown.
* </li>
* <li>
* Platform default <code>SchemaFactory</code> is located
* in a implementation specific way. There must be a platform default
* <code>SchemaFactory</code> for W3C XML Schema.
* </li>
* </ol>
*
* <p>If everything fails, {@link IllegalArgumentException} will be thrown.</p>
*
* <p><strong>Tip for Trouble-shooting:</strong></p>
* <p>See {@link java.util.Properties#load(java.io.InputStream)} for
* exactly how a property file is parsed. In particular, colons ':'
* need to be escaped in a property file, so make sure schema language
* URIs are properly escaped in it. For example:</p>
* <pre>
* http\://www.w3.org/2001/XMLSchema=org.acme.foo.XSSchemaFactory
* </pre>
*
* @param schemaLanguage
* Specifies the schema language which the returned
* SchemaFactory will understand. See
* <a href="#schemaLanguage">the list of available
* schema languages</a> for the possible values.
*
* @return New instance of a <code>SchemaFactory</code>
*
* @throws IllegalArgumentException
* If no implementation of the schema language is available.
* @throws NullPointerException
* If the <code>schemaLanguage</code> parameter is null.
* @throws SchemaFactoryConfigurationError
* If a configuration error is encountered.
*
* @see #newInstance(String schemaLanguage, String factoryClassName, ClassLoader classLoader)
*/
public static SchemaFactory newInstance(String schemaLanguage) {
ClassLoader cl;
cl = ss.getContextClassLoader();
if (cl == null) {
//cl = ClassLoader.getSystemClassLoader();
//use the current class loader
cl = SchemaFactory.class.getClassLoader();
}
SchemaFactory f = new SchemaFactoryFinder(cl).newFactory(schemaLanguage);
if (f == null) {
throw new IllegalArgumentException(
"No SchemaFactory"
+ " that implements the schema language specified by: " + schemaLanguage
+ " could be loaded");
}
return f;
}
/**
* <p>Obtain a new instance of a <code>SchemaFactory</code> from class name. <code>SchemaFactory</code>
* is returned if specified factory class name supports the specified schema language.
* This function is useful when there are multiple providers in the classpath.
* It gives more control to the application as it can specify which provider
* should be loaded.</p>
*
* <h2>Tip for Trouble-shooting</h2>
* <p>Setting the <code>jaxp.debug</code> system property will cause
* this method to print a lot of debug messages
* to <code>System.err</code> about what it is doing and where it is looking at.</p>
*
* <p> If you have problems try:</p>
* <pre>
* java -Djaxp.debug=1 YourProgram ....
* </pre>
*
* @param schemaLanguage Specifies the schema language which the returned
* <code>SchemaFactory</code> will understand. See
* <a href="#schemaLanguage">the list of available
* schema languages</a> for the possible values.
*
* @param factoryClassName fully qualified factory class name that provides implementation of <code>javax.xml.validation.SchemaFactory</code>.
*
* @param classLoader <code>ClassLoader</code> used to load the factory class. If <code>null</code>
* current <code>Thread</code>'s context classLoader is used to load the factory class.
*
* @return New instance of a <code>SchemaFactory</code>
*
* @throws IllegalArgumentException
* if <code>factoryClassName</code> is <code>null</code>, or
* the factory class cannot be loaded, instantiated or doesn't
* support the schema language specified in <code>schemLanguage</code>
* parameter.
*
* @throws NullPointerException
* If the <code>schemaLanguage</code> parameter is null.
*
* @see #newInstance(String schemaLanguage)
*
* @since 1.6
*/
public static SchemaFactory newInstance(String schemaLanguage, String factoryClassName, ClassLoader classLoader){
ClassLoader cl = classLoader;
if (cl == null) {
cl = ss.getContextClassLoader();
}
SchemaFactory f = new SchemaFactoryFinder(cl).createInstance(factoryClassName);
if (f == null) {
throw new IllegalArgumentException(
"Factory " + factoryClassName
+ " could not be loaded to implement the schema language specified by: " + schemaLanguage);
}
//if this factory supports the given schemalanguage return this factory else thrown exception
if(f.isSchemaLanguageSupported(schemaLanguage)){
return f;
}else{
throw new IllegalArgumentException(
"Factory " + f.getClass().getName()
+ " does not implement the schema language specified by: " + schemaLanguage);
}
}
/**
* <p>Is specified schema supported by this <code>SchemaFactory</code>?</p>
*
* @param schemaLanguage Specifies the schema language which the returned <code>SchemaFactory</code> will understand.
* <code>schemaLanguage</code> must specify a <a href="#schemaLanguage">valid</a> schema language.
*
* @return <code>true</code> if <code>SchemaFactory</code> supports <code>schemaLanguage</code>, else <code>false</code>.
*
* @throws NullPointerException If <code>schemaLanguage</code> is <code>null</code>.
* @throws IllegalArgumentException If <code>schemaLanguage.length() == 0</code>
* or <code>schemaLanguage</code> does not specify a <a href="#schemaLanguage">valid</a> schema language.
*/
public abstract boolean isSchemaLanguageSupported(String schemaLanguage);
/**
* Look up the value of a feature flag.
*
* <p>The feature name is any fully-qualified URI. It is
* possible for a {@link SchemaFactory} to recognize a feature name but
* temporarily be unable to return its value.
*
* <p>Implementors are free (and encouraged) to invent their own features,
* using names built on their own URIs.</p>
*
* @param name The feature name, which is a non-null fully-qualified URI.
*
* @return The current value of the feature (true or false).
*
* @throws SAXNotRecognizedException If the feature
* value can't be assigned or retrieved.
* @throws SAXNotSupportedException When the
* {@link SchemaFactory} recognizes the feature name but
* cannot determine its value at this time.
* @throws NullPointerException If <code>name</code> is <code>null</code>.
*
* @see #setFeature(String, boolean)
*/
public boolean getFeature(String name)
throws SAXNotRecognizedException, SAXNotSupportedException {
if (name == null) {
throw new NullPointerException("the name parameter is null");
}
throw new SAXNotRecognizedException(name);
}
/**
* <p>Set a feature for this <code>SchemaFactory</code>,
* {@link Schema}s created by this factory, and by extension,
* {@link Validator}s and {@link ValidatorHandler}s created by
* those {@link Schema}s.
* </p>
*
* <p>Implementors and developers should pay particular attention
* to how the special {@link Schema} object returned by {@link
* #newSchema()} is processed. In some cases, for example, when the
* <code>SchemaFactory</code> and the class actually loading the
* schema come from different implementations, it may not be possible
* for <code>SchemaFactory</code> features to be inherited automatically.
* Developers should
* make sure that features, such as secure processing, are explicitly
* set in both places.</p>
*
* <p>The feature name is any fully-qualified URI. It is
* possible for a {@link SchemaFactory} to expose a feature value but
* to be unable to change the current value.</p>
*
* <p>All implementations are required to support the {@link javax.xml.XMLConstants#FEATURE_SECURE_PROCESSING} feature.
* When the feature is:</p>
* <ul>
* <li>
* <code>true</code>: the implementation will limit XML processing to conform to implementation limits.
* Examples include enity expansion limits and XML Schema constructs that would consume large amounts of resources.
* If XML processing is limited for security reasons, it will be reported via a call to the registered
* {@link ErrorHandler#fatalError(SAXParseException exception)}.
* See {@link #setErrorHandler(ErrorHandler errorHandler)}.
* </li>
* <li>
* <code>false</code>: the implementation will processing XML according to the XML specifications without
* regard to possible implementation limits.
* </li>
* </ul>
*
* @param name The feature name, which is a non-null fully-qualified URI.
* @param value The requested value of the feature (true or false).
*
* @throws SAXNotRecognizedException If the feature
* value can't be assigned or retrieved.
* @throws SAXNotSupportedException When the
* {@link SchemaFactory} recognizes the feature name but
* cannot set the requested value.
* @throws NullPointerException If <code>name</code> is <code>null</code>.
*
* @see #getFeature(String)
*/
public void setFeature(String name, boolean value)
throws SAXNotRecognizedException, SAXNotSupportedException {
if (name == null) {
throw new NullPointerException("the name parameter is null");
}
throw new SAXNotRecognizedException(name);
}
/**
* Set the value of a property.
*
* <p>The property name is any fully-qualified URI. It is
* possible for a {@link SchemaFactory} to recognize a property name but
* to be unable to change the current value.</p>
*
* <p>
* All implementations that implement JAXP 1.5 or newer are required to
* support the {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_DTD} and
* {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_SCHEMA} properties.
* </p>
* <ul>
* <li>
* <p>Access to external DTDs in Schema files is restricted to the protocols
* specified by the {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_DTD} property.
* If access is denied during the creation of new Schema due to the restriction
* of this property, {@link org.xml.sax.SAXException} will be thrown by the
* {@link #newSchema(Source)} or {@link #newSchema(File)}
* or {@link #newSchema(URL)} or or {@link #newSchema(Source[])} method.</p>
*
* <p>Access to external DTDs in xml source files is restricted to the protocols
* specified by the {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_DTD} property.
* If access is denied during validation due to the restriction
* of this property, {@link org.xml.sax.SAXException} will be thrown by the
* {@link javax.xml.validation.Validator#validate(Source)} or
* {@link javax.xml.validation.Validator#validate(Source, Result)} method.</p>
*
* <p>Access to external reference set by the schemaLocation attribute is
* restricted to the protocols specified by the
* {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_SCHEMA} property.
* If access is denied during validation due to the restriction of this property,
* {@link org.xml.sax.SAXException} will be thrown by the
* {@link javax.xml.validation.Validator#validate(Source)} or
* {@link javax.xml.validation.Validator#validate(Source, Result)} method.</p>
*
* <p>Access to external reference set by the Import
* and Include element is restricted to the protocols specified by the
* {@link javax.xml.XMLConstants#ACCESS_EXTERNAL_SCHEMA} property.
* If access is denied during the creation of new Schema due to the restriction
* of this property, {@link org.xml.sax.SAXException} will be thrown by the
* {@link #newSchema(Source)} or {@link #newSchema(File)}
* or {@link #newSchema(URL)} or {@link #newSchema(Source[])} method.</p>
* </li>
* </ul>
*
* @param name The property name, which is a non-null fully-qualified URI.
* @param object The requested value for the property.
*
* @throws SAXNotRecognizedException If the property
* value can't be assigned or retrieved.
* @throws SAXNotSupportedException When the
* {@link SchemaFactory} recognizes the property name but
* cannot set the requested value.
* @throws NullPointerException If <code>name</code> is <code>null</code>.
*/
public void setProperty(String name, Object object)
throws SAXNotRecognizedException, SAXNotSupportedException {
if (name == null) {
throw new NullPointerException("the name parameter is null");
}
throw new SAXNotRecognizedException(name);
}
/**
* Look up the value of a property.
*
* <p>The property name is any fully-qualified URI. It is
* possible for a {@link SchemaFactory} to recognize a property name but
* temporarily be unable to return its value.</p>
*
* <p>{@link SchemaFactory}s are not required to recognize any specific
* property names.</p>
*
* <p>Implementors are free (and encouraged) to invent their own properties,
* using names built on their own URIs.</p>
*
* @param name The property name, which is a non-null fully-qualified URI.
*
* @return The current value of the property.
*
* @throws SAXNotRecognizedException If the property
* value can't be assigned or retrieved.
* @throws SAXNotSupportedException When the
* XMLReader recognizes the property name but
* cannot determine its value at this time.
* @throws NullPointerException If <code>name</code> is <code>null</code>.
*
* @see #setProperty(String, Object)
*/
public Object getProperty(String name)
throws SAXNotRecognizedException, SAXNotSupportedException {
if (name == null) {
throw new NullPointerException("the name parameter is null");
}
throw new SAXNotRecognizedException(name);
}
/**
* Sets the {@link ErrorHandler} to receive errors encountered
* during the <code>newSchema</code> method invocation.
*
* <p>
* Error handler can be used to customize the error handling process
* during schema parsing. When an {@link ErrorHandler} is set,
* errors found during the parsing of schemas will be first sent
* to the {@link ErrorHandler}.
*
* <p>
* The error handler can abort the parsing of a schema immediately
* by throwing {@link SAXException} from the handler. Or for example
* it can print an error to the screen and try to continue the
* processing by returning normally from the {@link ErrorHandler}
*
* <p>
* If any {@link Throwable} (or instances of its derived classes)
* is thrown from an {@link ErrorHandler},
* the caller of the <code>newSchema</code> method will be thrown
* the same {@link Throwable} object.
*
* <p>
* {@link SchemaFactory} is not allowed to
* throw {@link SAXException} without first reporting it to
* {@link ErrorHandler}.
*
* <p>
* Applications can call this method even during a {@link Schema}
* is being parsed.
*
* <p>
* When the {@link ErrorHandler} is null, the implementation will
* behave as if the following {@link ErrorHandler} is set:
* <pre>
* class DraconianErrorHandler implements {@link ErrorHandler} {
* public void fatalError( {@link org.xml.sax.SAXParseException} e ) throws {@link SAXException} {
* throw e;
* }
* public void error( {@link org.xml.sax.SAXParseException} e ) throws {@link SAXException} {
* throw e;
* }
* public void warning( {@link org.xml.sax.SAXParseException} e ) throws {@link SAXException} {
* // noop
* }
* }
* </pre>
*
* <p>
* When a new {@link SchemaFactory} object is created, initially
* this field is set to null. This field will <em>NOT</em> be
* inherited to {@link Schema}s, {@link Validator}s, or
* {@link ValidatorHandler}s that are created from this {@link SchemaFactory}.
*
* @param errorHandler A new error handler to be set.
* This parameter can be <code>null</code>.
*/
public abstract void setErrorHandler(ErrorHandler errorHandler);
/**
* Gets the current {@link ErrorHandler} set to this {@link SchemaFactory}.
*
* @return
* This method returns the object that was last set through
* the {@link #setErrorHandler(ErrorHandler)} method, or null
* if that method has never been called since this {@link SchemaFactory}
* has created.
*
* @see #setErrorHandler(ErrorHandler)
*/
public abstract ErrorHandler getErrorHandler();
/**
* Sets the {@link LSResourceResolver} to customize
* resource resolution when parsing schemas.
*
* <p>
* {@link SchemaFactory} uses a {@link LSResourceResolver}
* when it needs to locate external resources while parsing schemas,
* although exactly what constitutes "locating external resources" is
* up to each schema language. For example, for W3C XML Schema,
* this includes files <code>&lt;include></code>d or <code>&lt;import></code>ed,
* and DTD referenced from schema files, etc.
*
* <p>
* Applications can call this method even during a {@link Schema}
* is being parsed.
*
* <p>
* When the {@link LSResourceResolver} is null, the implementation will
* behave as if the following {@link LSResourceResolver} is set:
* <pre>
* class DumbDOMResourceResolver implements {@link LSResourceResolver} {
* public {@link org.w3c.dom.ls.LSInput} resolveResource(
* String publicId, String systemId, String baseURI) {
*
* return null; // always return null
* }
* }
* </pre>
*
* <p>
* If a {@link LSResourceResolver} throws a {@link RuntimeException}
* (or instances of its derived classes),
* then the {@link SchemaFactory} will abort the parsing and
* the caller of the <code>newSchema</code> method will receive
* the same {@link RuntimeException}.
*
* <p>
* When a new {@link SchemaFactory} object is created, initially
* this field is set to null. This field will <em>NOT</em> be
* inherited to {@link Schema}s, {@link Validator}s, or
* {@link ValidatorHandler}s that are created from this {@link SchemaFactory}.
*
* @param resourceResolver
* A new resource resolver to be set. This parameter can be null.
*/
public abstract void setResourceResolver(LSResourceResolver resourceResolver);
/**
* Gets the current {@link LSResourceResolver} set to this {@link SchemaFactory}.
*
* @return
* This method returns the object that was last set through
* the {@link #setResourceResolver(LSResourceResolver)} method, or null
* if that method has never been called since this {@link SchemaFactory}
* has created.
*
* @see #setErrorHandler(ErrorHandler)
*/
public abstract LSResourceResolver getResourceResolver();
/**
* <p>Parses the specified source as a schema and returns it as a schema.</p>
*
* <p>This is a convenience method for {@link #newSchema(Source[] schemas)}.</p>
*
* @param schema Source that represents a schema.
*
* @return New <code>Schema</code> from parsing <code>schema</code>.
*
* @throws SAXException If a SAX error occurs during parsing.
* @throws NullPointerException if <code>schema</code> is null.
*/
public Schema newSchema(Source schema) throws SAXException {
return newSchema(new Source[]{schema});
}
/**
* <p>Parses the specified <code>File</code> as a schema and returns it as a <code>Schema</code>.</p>
*
* <p>This is a convenience method for {@link #newSchema(Source schema)}.</p>
*
* @param schema File that represents a schema.
*
* @return New <code>Schema</code> from parsing <code>schema</code>.
*
* @throws SAXException If a SAX error occurs during parsing.
* @throws NullPointerException if <code>schema</code> is null.
*/
public Schema newSchema(File schema) throws SAXException {
return newSchema(new StreamSource(schema));
}
/**
* <p>Parses the specified <code>URL</code> as a schema and returns it as a <code>Schema</code>.</p>
*
* <p>This is a convenience method for {@link #newSchema(Source schema)}.</p>
*
* @param schema <code>URL</code> that represents a schema.
*
* @return New <code>Schema</code> from parsing <code>schema</code>.
*
* @throws SAXException If a SAX error occurs during parsing.
* @throws NullPointerException if <code>schema</code> is null.
*/
public Schema newSchema(URL schema) throws SAXException {
return newSchema(new StreamSource(schema.toExternalForm()));
}
/**
* Parses the specified source(s) as a schema and returns it as a schema.
*
* <p>
* The callee will read all the {@link Source}s and combine them into a
* single schema. The exact semantics of the combination depends on the schema
* language that this {@link SchemaFactory} object is created for.
*
* <p>
* When an {@link ErrorHandler} is set, the callee will report all the errors
* found in sources to the handler. If the handler throws an exception, it will
* abort the schema compilation and the same exception will be thrown from
* this method. Also, after an error is reported to a handler, the callee is allowed
* to abort the further processing by throwing it. If an error handler is not set,
* the callee will throw the first error it finds in the sources.
*
* <h2>W3C XML Schema 1.0</h2>
* <p>
* The resulting schema contains components from the specified sources.
* The same result would be achieved if all these sources were
* imported, using appropriate values for schemaLocation and namespace,
* into a single schema document with a different targetNamespace
* and no components of its own, if the import elements were given
* in the same order as the sources. Section 4.2.3 of the XML Schema
* recommendation describes the options processors have in this
* regard. While a processor should be consistent in its treatment of
* JAXP schema sources and XML Schema imports, the behaviour between
* JAXP-compliant parsers may vary; in particular, parsers may choose
* to ignore all but the first &lt;import> for a given namespace,
* regardless of information provided in schemaLocation.
*
* <p>
* If the parsed set of schemas includes error(s) as
* specified in the section 5.1 of the XML Schema spec, then
* the error must be reported to the {@link ErrorHandler}.
*
* <h2>RELAX NG</h2>
*
* <p>For RELAX NG, this method must throw {@link UnsupportedOperationException}
* if <code>schemas.length!=1</code>.
*
*
* @param schemas
* inputs to be parsed. {@link SchemaFactory} is required
* to recognize {@link javax.xml.transform.sax.SAXSource},
* {@link StreamSource},
* {@link javax.xml.transform.stax.StAXSource},
* and {@link javax.xml.transform.dom.DOMSource}.
* Input schemas must be XML documents or
* XML elements and must not be null. For backwards compatibility,
* the results of passing anything other than
* a document or element are implementation-dependent.
* Implementations must either recognize and process the input
* or thrown an IllegalArgumentException.
*
* @return
* Always return a non-null valid {@link Schema} object.
* Note that when an error has been reported, there is no
* guarantee that the returned {@link Schema} object is
* meaningful.
*
* @throws SAXException
* If an error is found during processing the specified inputs.
* When an {@link ErrorHandler} is set, errors are reported to
* there first. See {@link #setErrorHandler(ErrorHandler)}.
* @throws NullPointerException
* If the <code>schemas</code> parameter itself is null or
* any item in the array is null.
* @throws IllegalArgumentException
* If any item in the array is not recognized by this method.
* @throws UnsupportedOperationException
* If the schema language doesn't support this operation.
*/
public abstract Schema newSchema(Source[] schemas) throws SAXException;
/**
* Creates a special {@link Schema} object.
*
* <p>The exact semantics of the returned {@link Schema} object
* depend on the schema language for which this {@link SchemaFactory}
* is created.
*
* <p>Also, implementations are allowed to use implementation-specific
* property/feature to alter the semantics of this method.</p>
*
* <p>Implementors and developers should pay particular attention
* to how the features set on this {@link SchemaFactory} are
* processed by this special {@link Schema}.
* In some cases, for example, when the
* {@link SchemaFactory} and the class actually loading the
* schema come from different implementations, it may not be possible
* for {@link SchemaFactory} features to be inherited automatically.
* Developers should
* make sure that features, such as secure processing, are explicitly
* set in both places.</p>
*
* <h2>W3C XML Schema 1.0</h2>
* <p>
* For XML Schema, this method creates a {@link Schema} object that
* performs validation by using location hints specified in documents.
*
* <p>
* The returned {@link Schema} object assumes that if documents
* refer to the same URL in the schema location hints,
* they will always resolve to the same schema document. This
* asusmption allows implementations to reuse parsed results of
* schema documents so that multiple validations against the same
* schema will run faster.
*
* <p>
* Note that the use of schema location hints introduces a
* vulnerability to denial-of-service attacks.
*
*
* <h2>RELAX NG</h2>
* <p>
* RELAX NG does not support this operation.
*
* @return
* Always return non-null valid {@link Schema} object.
*
* @throws UnsupportedOperationException
* If this operation is not supported by the callee.
* @throws SAXException
* If this operation is supported but failed for some reason.
*/
public abstract Schema newSchema() throws SAXException;
}