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* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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package javax.xml.transform;
/**
* <p>A TransformerFactory instance can be used to create
* {@link javax.xml.transform.Transformer} and
* {@link javax.xml.transform.Templates} objects.</p>
*
* <p>The system property that determines which Factory implementation
* to create is named <code>"javax.xml.transform.TransformerFactory"</code>.
* This property names a concrete subclass of the
* <code>TransformerFactory</code> abstract class. If the property is not
* defined, a platform default is be used.</p>
*
* @author <a href="mailto:Jeff.Suttor@Sun.com">Jeff Suttor</a>
* @author <a href="mailto:Neeraj.Bajaj@sun.com">Neeraj Bajaj</a>
*
*/
public abstract class TransformerFactory {
/**
* Default constructor is protected on purpose.
*/
protected TransformerFactory() { }
/**
* <p>Obtain a new instance of a <code>TransformerFactory</code>.
* This static method creates a new factory instance
* This method uses the following ordered lookup procedure to determine
* the <code>TransformerFactory</code> implementation class to
* load:</p>
* <ul>
* <li>
* Use the <code>javax.xml.transform.TransformerFactory</code> system
* property.
* </li>
* <li>
* Use the properties file "lib/jaxp.properties" in the JRE directory.
* This configuration file is in standard <code>java.util.Properties
* </code> format and contains the fully qualified name of the
* implementation class with the key being the system property defined
* above.
*
* The jaxp.properties file is read only once by the JAXP implementation
* and it's values are then cached for future use. If the file does not exist
* when the first attempt is made to read from it, no further attempts are
* made to check for its existence. It is not possible to change the value
* of any property in jaxp.properties after it has been read for the first time.
* </li>
* <li>
* Use the Services API (as detailed in the JAR specification), if
* available, to determine the classname. The Services API will look
* for a classname in the file
* <code>META-INF/services/javax.xml.transform.TransformerFactory</code>
* in jars available to the runtime.
* </li>
* <li>
* Platform default <code>TransformerFactory</code> instance.
* </li>
* </ul>
*
* <p>Once an application has obtained a reference to a <code>
* TransformerFactory</code> it can use the factory to configure
* and obtain transformer instances.</p>
*
* @return new TransformerFactory instance, never null.
*
* @throws TransformerFactoryConfigurationError Thrown if the implementation
* is not available or cannot be instantiated.
*/
public static TransformerFactory newInstance()
throws TransformerFactoryConfigurationError {
try {
return (TransformerFactory) FactoryFinder.find(
/* The default property name according to the JAXP spec */
"javax.xml.transform.TransformerFactory",
/* The fallback implementation class name, XSLTC */
"com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl");
} catch (FactoryFinder.ConfigurationError e) {
throw new TransformerFactoryConfigurationError(
e.getException(),
e.getMessage());
}
}
/**
* <p>Obtain a new instance of a <code>TransformerFactory</code> from factory class name.
* 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>
*
* <p>Once an application has obtained a reference to a <code>
* TransformerFactory</code> it can use the factory to configure
* and obtain transformer instances.</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 factoryClassName fully qualified factory class name that provides implementation of <code>javax.xml.transform.TransformerFactory</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 TransformerFactory instance, never null.
*
* @throws TransformerFactoryConfigurationError
* if <code>factoryClassName</code> is <code>null</code>, or
* the factory class cannot be loaded, instantiated.
*
* @see #newInstance()
*
* @since 1.6
*/
public static TransformerFactory newInstance(String factoryClassName, ClassLoader classLoader)
throws TransformerFactoryConfigurationError{
try {
//do not fallback if given classloader can't find the class, throw exception
return (TransformerFactory) FactoryFinder.newInstance(factoryClassName, classLoader, false);
} catch (FactoryFinder.ConfigurationError e) {
throw new TransformerFactoryConfigurationError(
e.getException(),
e.getMessage());
}
}
/**
* <p>Process the <code>Source</code> into a <code>Transformer</code>
* <code>Object</code>. The <code>Source</code> is an XSLT document that
* conforms to <a href="http://www.w3.org/TR/xslt">
* XSL Transformations (XSLT) Version 1.0</a>. Care must
* be taken not to use this <code>Transformer</code> in multiple
* <code>Thread</code>s running concurrently.
* Different <code>TransformerFactories</code> can be used concurrently by
* different <code>Thread</code>s.</p>
*
* @param source <code>Source </code> of XSLT document used to create
* <code>Transformer</code>.
* Examples of XML <code>Source</code>s include
* {@link javax.xml.transform.dom.DOMSource DOMSource},
* {@link javax.xml.transform.sax.SAXSource SAXSource}, and
* {@link javax.xml.transform.stream.StreamSource StreamSource}.
*
* @return A <code>Transformer</code> object that may be used to perform
* a transformation in a single <code>Thread</code>, never
* <code>null</code>.
*
* @throws TransformerConfigurationException Thrown if there are errors when
* parsing the <code>Source</code> or it is not possible to create a
* <code>Transformer</code> instance.
*
* @see <a href="http://www.w3.org/TR/xslt">
* XSL Transformations (XSLT) Version 1.0</a>
*/
public abstract Transformer newTransformer(Source source)
throws TransformerConfigurationException;
/**
* <p>Create a new <code>Transformer</code> that performs a copy
* of the <code>Source</code> to the <code>Result</code>.
* i.e. the "<em>identity transform</em>".</p>
*
* @return A Transformer object that may be used to perform a transformation
* in a single thread, never null.
*
* @throws TransformerConfigurationException When it is not
* possible to create a <code>Transformer</code> instance.
*/
public abstract Transformer newTransformer()
throws TransformerConfigurationException;
/**
* Process the Source into a Templates object, which is a
* a compiled representation of the source. This Templates object
* may then be used concurrently across multiple threads. Creating
* a Templates object allows the TransformerFactory to do detailed
* performance optimization of transformation instructions, without
* penalizing runtime transformation.
*
* @param source An object that holds a URL, input stream, etc.
*
* @return A Templates object capable of being used for transformation
* purposes, never <code>null</code>.
*
* @throws TransformerConfigurationException When parsing to
* construct the Templates object fails.
*/
public abstract Templates newTemplates(Source source)
throws TransformerConfigurationException;
/**
* <p>Get the stylesheet specification(s) associated with the
* XML <code>Source</code> document via the
* <a href="http://www.w3.org/TR/xml-stylesheet/">
* xml-stylesheet processing instruction</a> that match the given criteria.
* Note that it is possible to return several stylesheets, in which case
* they are applied as if they were a list of imports or cascades in a
* single stylesheet.</p>
*
* @param source The XML source document.
* @param media The media attribute to be matched. May be null, in which
* case the prefered templates will be used (i.e. alternate = no).
* @param title The value of the title attribute to match. May be null.
* @param charset The value of the charset attribute to match. May be null.
*
* @return A <code>Source</code> <code>Object</code> suitable for passing
* to the <code>TransformerFactory</code>.
*
* @throws TransformerConfigurationException An <code>Exception</code>
* is thrown if an error occurings during parsing of the
* <code>source</code>.
*
* @see <a href="http://www.w3.org/TR/xml-stylesheet/">
* Associating Style Sheets with XML documents Version 1.0</a>
*/
public abstract Source getAssociatedStylesheet(
Source source,
String media,
String title,
String charset)
throws TransformerConfigurationException;
/**
* Set an object that is used by default during the transformation
* to resolve URIs used in document(), xsl:import, or xsl:include.
*
* @param resolver An object that implements the URIResolver interface,
* or null.
*/
public abstract void setURIResolver(URIResolver resolver);
/**
* Get the object that is used by default during the transformation
* to resolve URIs used in document(), xsl:import, or xsl:include.
*
* @return The URIResolver that was set with setURIResolver.
*/
public abstract URIResolver getURIResolver();
//======= CONFIGURATION METHODS =======
/**
* <p>Set a feature for this <code>TransformerFactory</code> and <code>Transformer</code>s
* or <code>Template</code>s created by this factory.</p>
*
* <p>
* Feature names are fully qualified {@link java.net.URI}s.
* Implementations may define their own features.
* An {@link TransformerConfigurationException} is thrown if this <code>TransformerFactory</code> or the
* <code>Transformer</code>s or <code>Template</code>s it creates cannot support the feature.
* It is possible for an <code>TransformerFactory</code> to expose a feature value but be unable to change its state.
* </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
* and behave in a secure fashion as defined by the implementation.
* Examples include resolving user defined style sheets and functions.
* If XML processing is limited for security reasons, it will be reported via a call to the registered
* {@link ErrorListener#fatalError(TransformerException exception)}.
* See {@link #setErrorListener(ErrorListener listener)}.
* </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 Feature name.
* @param value Is feature state <code>true</code> or <code>false</code>.
*
* @throws TransformerConfigurationException if this <code>TransformerFactory</code>
* or the <code>Transformer</code>s or <code>Template</code>s it creates cannot support this feature.
* @throws NullPointerException If the <code>name</code> parameter is null.
*/
public abstract void setFeature(String name, boolean value)
throws TransformerConfigurationException;
/**
* Look up the value of a feature.
*
* <p>
* Feature names are fully qualified {@link java.net.URI}s.
* Implementations may define their own features.
* <code>false</code> is returned if this <code>TransformerFactory</code> or the
* <code>Transformer</code>s or <code>Template</code>s it creates cannot support the feature.
* It is possible for an <code>TransformerFactory</code> to expose a feature value but be unable to change its state.
* </p>
*
* @param name Feature name.
*
* @return The current state of the feature, <code>true</code> or <code>false</code>.
*
* @throws NullPointerException If the <code>name</code> parameter is null.
*/
public abstract boolean getFeature(String name);
/**
* Allows the user to set specific attributes on the underlying
* implementation. An attribute in this context is defined to
* be an option that the implementation provides.
* An <code>IllegalArgumentException</code> is thrown if the underlying
* implementation doesn't recognize the attribute.
*
* @param name The name of the attribute.
* @param value The value of the attribute.
*
* @throws IllegalArgumentException When implementation does not
* recognize the attribute.
*/
public abstract void setAttribute(String name, Object value);
/**
* Allows the user to retrieve specific attributes on the underlying
* implementation.
* An <code>IllegalArgumentException</code> is thrown if the underlying
* implementation doesn't recognize the attribute.
*
* @param name The name of the attribute.
*
* @return value The value of the attribute.
*
* @throws IllegalArgumentException When implementation does not
* recognize the attribute.
*/
public abstract Object getAttribute(String name);
/**
* Set the error event listener for the TransformerFactory, which
* is used for the processing of transformation instructions,
* and not for the transformation itself.
* An <code>IllegalArgumentException</code> is thrown if the
* <code>ErrorListener</code> listener is <code>null</code>.
*
* @param listener The new error listener.
*
* @throws IllegalArgumentException When <code>listener</code> is
* <code>null</code>
*/
public abstract void setErrorListener(ErrorListener listener);
/**
* Get the error event handler for the TransformerFactory.
*
* @return The current error handler, which should never be null.
*/
public abstract ErrorListener getErrorListener();
}