An instance of this class can be obtained with the
* TransformerFactory.newTransformer method. This instance may
* then be used to process XML from a variety of sources and write
* the transformation output to a variety of sinks.
An object of this class may not be used in multiple threads * running concurrently. Different Transformers may be used * concurrently by different threads.
* *A Transformer may be used multiple times. Parameters and * output properties are preserved across transformations.
*/ public abstract class Transformer { /** * Default constructor is protected on purpose. */ protected Transformer() {} /** * Process the source tree to the output result. * @param xmlSource The input for the source tree. * @param outputTarget The output target. * * @throws TransformerException If an unrecoverable error occurs * during the course of the transformation. */ public abstract void transform(Source xmlSource, Result outputTarget) throws TransformerException; /** * Add a parameter for the transformation. * *Pass a qualified name as a two-part string, the namespace URI * enclosed in curly braces ({}), followed by the local name. If the * name has a null URL, the String only contain the local name. An * application can safely check for a non-null URI by testing to see if the first * character of the name is a '{' character.
*For example, if a URI and local name were obtained from an element * defined with <xyz:foo xmlns:xyz="http://xyz.foo.com/yada/baz.html"/>, * then the qualified name would be "{http://xyz.foo.com/yada/baz.html}foo". Note that * no prefix is used.
* * @param name The name of the parameter, which may begin with a namespace URI * in curly braces ({}). * @param value The value object. This can be any valid Java object. It is * up to the processor to provide the proper object coersion or to simply * pass the object on for use in an extension. */ public abstract void setParameter(String name, Object value); /** * Get a parameter that was explicitly set with setParameter * or setParameters. * *This method does not return a default parameter value, which * cannot be determined until the node context is evaluated during * the transformation process. * * @return A parameter that has been set with setParameter, or null if * a parameter with the given name was not found. */ public abstract Object getParameter(String name); /** * Clear all parameters set with setParameter. */ public abstract void clearParameters(); /** * Set an object that will be used to resolve URIs used in * document(). * *
If the resolver argument is null, the URIResolver value will * be cleared, and the default behavior will be used.
* * @param resolver An object that implements the URIResolver interface, * or null. */ public abstract void setURIResolver(URIResolver resolver); /** * Get an object that will be used to resolve URIs used in * document(), etc. * * @return An object that implements the URIResolver interface, * or null. */ public abstract URIResolver getURIResolver(); /** * Set the output properties for the transformation. These * properties will override properties set in the Templates * with xsl:output. * *If argument to this function is null, any properties * previously set are removed, and the value will revert to the value * defined in the templates object.
* *Pass a qualified property key name as a two-part string, the namespace URI * enclosed in curly braces ({}), followed by the local name. If the * name has a null URL, the String only contain the local name. An * application can safely check for a non-null URI by testing to see if the first * character of the name is a '{' character.
*For example, if a URI and local name were obtained from an element * defined with <xyz:foo xmlns:xyz="http://xyz.foo.com/yada/baz.html"/>, * then the qualified name would be "{http://xyz.foo.com/yada/baz.html}foo". Note that * no prefix is used.
* * @param oformat A set of output properties that will be * used to override any of the same properties in affect * for the transformation. * * @see javax.xml.transform.OutputKeys * @see java.util.Properties * * @throws IllegalArgumentException if any of the argument keys are not * recognized and are not namespace qualified. */ public abstract void setOutputProperties(Properties oformat) throws IllegalArgumentException; /** * Get a copy of the output properties for the transformation. * *The properties returned should contain properties set by the user, * and properties set by the stylesheet, and these properties * are "defaulted" by default properties specified by section 16 of the * XSL Transformations (XSLT) W3C Recommendation. The properties that * were specifically set by the user or the stylesheet should be in the base * Properties list, while the XSLT default properties that were not * specifically set should be the default Properties list. Thus, * getOutputProperties().getProperty(String key) will obtain any * property in that was set by {@link #setOutputProperty}, * {@link #setOutputProperties}, in the stylesheet, or the default * properties, while * getOutputProperties().get(String key) will only retrieve properties * that were explicitly set by {@link #setOutputProperty}, * {@link #setOutputProperties}, or in the stylesheet.
* *Note that mutation of the Properties object returned will not * effect the properties that the transformation contains.
* *If any of the argument keys are not recognized and are not * namespace qualified, the property will be ignored. In other words the * behaviour is not orthogonal with setOutputProperties.
* * @returns A copy of the set of output properties in effect * for the next transformation. * * @see javax.xml.transform.OutputKeys * @see java.util.Properties */ public abstract Properties getOutputProperties(); /** * Set an output property that will be in effect for the * transformation. * *Pass a qualified property name as a two-part string, the namespace URI * enclosed in curly braces ({}), followed by the local name. If the * name has a null URL, the String only contain the local name. An * application can safely check for a non-null URI by testing to see if the first * character of the name is a '{' character.
*For example, if a URI and local name were obtained from an element * defined with <xyz:foo xmlns:xyz="http://xyz.foo.com/yada/baz.html"/>, * then the qualified name would be "{http://xyz.foo.com/yada/baz.html}foo". Note that * no prefix is used.
* *The Properties object that was passed to {@link #setOutputProperties} won't * be effected by calling this method.
* * @param name A non-null String that specifies an output * property name, which may be namespace qualified. * @param value The non-null string value of the output property. * * @throws IllegalArgumentException If the property is not supported, and is * not qualified with a namespace. * * @see javax.xml.transform.OutputKeys */ public abstract void setOutputProperty(String name, String value) throws IllegalArgumentException; /** * Get an output property that is in effect for the * transformation. The property specified may be a property * that was set with setOutputProperty, or it may be a * property specified in the stylesheet. * * @param name A non-null String that specifies an output * property name, which may be namespace qualified. * * @return The string value of the output property, or null * if no property was found. * * @throws IllegalArgumentException If the property is not supported. * * @see javax.xml.transform.OutputKeys */ public abstract String getOutputProperty(String name) throws IllegalArgumentException; /** * Set the error event listener in effect for the transformation. * * @param listener The new error listener. * @throws IllegalArgumentException if listener is null. */ public abstract void setErrorListener(ErrorListener listener) throws IllegalArgumentException; /** * Get the error event handler in effect for the transformation. * * @return The current error handler, which should never be null. */ public abstract ErrorListener getErrorListener(); }