luni/src/main/java/javax/xml/transform/package.html - platform/libcore-snapshot - Git at Google

 <?xml version="1.0"?>
 <!-- $Id: package.html 226183 2005-04-08 10:39:14Z neeraj $ -->

 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
 <html xmlns="http://www.w3.org/1999/xhtml">
 <head>
 <title>javax.xml.transform</title>
 </head>

 <body>
 <p>This package defines the generic APIs for processing transformation
 instructions, and performing a transformation from source to result. These
 interfaces have no dependencies on SAX or the DOM standard, and try to make as
 few assumptions as possible about the details of the source and result of a
 transformation. It achieves this by defining
 {@link javax.xml.transform.Source} and
 {@link javax.xml.transform.Result} interfaces.
 </p>

 <p>To define concrete classes for the user, the API defines specializations
 of the interfaces found at the root level. These interfaces are found in
 {@link javax.xml.transform.sax}, {@link javax.xml.transform.dom},
 and {@link javax.xml.transform.stream}.
 </p>


 <h3>Creating Objects</h3>

 <p>The API allows a concrete
 {@link javax.xml.transform.TransformerFactory} object to be created from
 the static function
 {@link javax.xml.transform.TransformerFactory#newInstance}.
 </p>


 <h3>Specification of Inputs and Outputs</h3>

 <p>This API defines two interface objects called
 {@link javax.xml.transform.Source} and
 {@link javax.xml.transform.Result}. In order to pass Source and Result
 objects to the interfaces, concrete classes must be used.
 Three concrete representations are defined for each of these
 objects:
 {@link javax.xml.transform.stream.StreamSource} and
 {@link javax.xml.transform.stream.StreamResult},
 {@link javax.xml.transform.sax.SAXSource} and
 {@link javax.xml.transform.sax.SAXResult}, and
 {@link javax.xml.transform.dom.DOMSource} and
 {@link javax.xml.transform.dom.DOMResult}. Each of these objects defines
 a FEATURE string (which is i the form of a URL), which can be passed into
 {@link javax.xml.transform.TransformerFactory#getFeature} to see if the
 given type of Source or Result object is supported. For instance, to test if a
 DOMSource and a StreamResult is supported, you can apply the following
 test.
 </p>

 <pre>
 <code>
 TransformerFactory tfactory = TransformerFactory.newInstance();
 if (tfactory.getFeature(DOMSource.FEATURE) &amp;&amp; tfactory.getFeature(StreamResult.FEATURE)) {
 ...
 }
 </code>
 </pre>


 <h3>
 <a name="qname-delimiter">Qualified Name Representation</a>
 </h3>

 <p><a href="http://www.w3.org/TR/REC-xml-names">Namespaces</a>
 present something of a problem area when dealing with XML objects. Qualified
 Names appear in XML markup as prefixed names. But the prefixes themselves do
 not hold identity. Rather, it is the URIs that they contextually map to that
 hold the identity. Therefore, when passing a Qualified Name like "xyz:foo"
 among Java programs, one must provide a means to map "xyz" to a namespace.
 </p>

 <p>One solution has been to create a "QName" object that holds the
 namespace URI, as well as the prefix and local name, but this is not always an
 optimal solution, as when, for example, you want to use unique strings as keys
 in a dictionary object. Not having a string representation also makes it
 difficult to specify a namespaced identity outside the context of an XML
 document.
 </p>

 <p>In order to pass namespaced values to transformations,
 for
 instance when setting a property or a parameter on a
 {@link javax.xml.transform.Transformer} object,
 this specification defines that a
 String "qname" object parameter be passed as two-part string, the namespace URI
 enclosed in curly braces ({}), followed by the local name. If the qname has a
 null URI, then the String object only contains 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.
 </p>

 <p>For example, if a URI and local name were obtained from an element
 defined with &lt;xyz:foo xmlns:xyz="http://xyz.foo.com/yada/baz.html"/&gt;,
 then the Qualified Name would be "{http://xyz.foo.com/yada/baz.html}foo".
 Note that the prefix is lost.
 </p>


 <h3>Result Tree Serialization</h3>

 <p>Serialization of the result tree to a stream can be controlled with
 the {@link javax.xml.transform.Transformer#setOutputProperties} and the
 {@link javax.xml.transform.Transformer#setOutputProperty} methods.
 These properties only apply to stream results, they have no effect when
 the result is a DOM tree or SAX event stream.</p>

 <p>Strings that match the <a href="http://www.w3.org/TR/xslt#output">XSLT
 specification for xsl:output attributes</a> can be referenced from the
 {@link javax.xml.transform.OutputKeys} class. Other strings can be
 specified as well.
 If the transformer does not recognize an output key, a
 {@link java.lang.IllegalArgumentException} is thrown, unless the
 key name is <a href="#qname-delimiter">namespace qualified</a>. Output key names
 that are namespace qualified are always allowed, although they may be
 ignored by some implementations.</p>

 <p>If all that is desired is the simple identity transformation of a
 source to a result, then {@link javax.xml.transform.TransformerFactory}
 provides a
 {@link javax.xml.transform.TransformerFactory#newTransformer()} method
 with no arguments. This method creates a Transformer that effectively copies
 the source to the result. This method may be used to create a DOM from SAX
 events or to create an XML or HTML stream from a DOM or SAX events.  </p>

 <h3>Exceptions and Error Reporting</h3>

 <p>The transformation API throw three types of specialized exceptions. A
 {@link javax.xml.transform.TransformerFactoryConfigurationError} is parallel to
 the {@link javax.xml.parsers.FactoryConfigurationError}, and is thrown
 when a configuration problem with the TransformerFactory exists. This error
 will typically be thrown when the transformation factory class specified with
 the "javax.xml.transform.TransformerFactory" system property cannot be found or
 instantiated.</p>

 <p>A {@link javax.xml.transform.TransformerConfigurationException}
 may be thrown if for any reason a Transformer can not be created. A
 TransformerConfigurationException may be thrown if there is a syntax error in
 the transformation instructions, for example when
 {@link javax.xml.transform.TransformerFactory#newTransformer} is
 called.</p>

 <p>{@link javax.xml.transform.TransformerException} is a general
 exception that occurs during the course of a transformation. A transformer
 exception may wrap another exception, and if any of the
 {@link javax.xml.transform.TransformerException#printStackTrace()}
 methods are called on it, it will produce a list of stack dumps, starting from
 the most recent. The transformer exception also provides a
 {@link javax.xml.transform.SourceLocator} object which indicates where
 in the source tree or transformation instructions the error occurred.
 {@link javax.xml.transform.TransformerException#getMessageAndLocation()}
 may be called to get an error message with location info, and
 {@link javax.xml.transform.TransformerException#getLocationAsString()}
 may be called to get just the location string.</p>

 <p>Transformation warnings and errors are sent to an
 {@link javax.xml.transform.ErrorListener}, at which point the
 application may decide to report the error or warning, and may decide to throw
 an <code>Exception</code> for a non-fatal error. The <code>ErrorListener</code> may be set via
 {@link javax.xml.transform.TransformerFactory#setErrorListener} for
 reporting errors that have to do with syntax errors in the transformation
 instructions, or via
 {@link javax.xml.transform.Transformer#setErrorListener} to report
 errors that occur during the transformation. The <code>ErrorListener</code> on both objects
 will always be valid and non-<code>null</code>, whether set by the application or a default
 implementation provided by the processor.
 The default implementation provided by the processor will report all warnings and errors to <code>System.err</code>
 and does not throw any <code>Exception</code>s.
 Applications are <em>strongly</em> encouraged to register and use
 <code>ErrorListener</code>s that insure proper behavior for warnings and
 errors.
 </p>


 <h3>Resolution of URIs within a transformation</h3>

 <p>The API provides a way for URIs referenced from within the stylesheet
 instructions or within the transformation to be resolved by the calling
 application. This can be done by creating a class that implements the
 {@link javax.xml.transform.URIResolver} interface, with its one method,
 {@link javax.xml.transform.URIResolver#resolve}, and use this class to
 set the URI resolution for the transformation instructions or transformation
 with {@link javax.xml.transform.TransformerFactory#setURIResolver} or
 {@link javax.xml.transform.Transformer#setURIResolver}. The
 <code>URIResolver.resolve</code> method takes two String arguments, the URI found in the
 stylesheet instructions or built as part of the transformation process, and the
 base URI
 against which the first argument will be made absolute if the
 absolute URI is required.
 The returned {@link javax.xml.transform.Source} object must be usable by
 the transformer, as specified in its implemented features.</p>


 </body>
 </html>
	<?xml version="1.0"?>
	<!-- $Id: package.html 226183 2005-04-08 10:39:14Z neeraj $ -->

	<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
	<html xmlns="http://www.w3.org/1999/xhtml">
	<head>
	<title>javax.xml.transform</title>
	</head>

	<body>
	<p>This package defines the generic APIs for processing transformation
	instructions, and performing a transformation from source to result. These
	interfaces have no dependencies on SAX or the DOM standard, and try to make as
	few assumptions as possible about the details of the source and result of a
	transformation. It achieves this by defining
	{@link javax.xml.transform.Source} and
	{@link javax.xml.transform.Result} interfaces.
	</p>

	<p>To define concrete classes for the user, the API defines specializations
	of the interfaces found at the root level. These interfaces are found in
	{@link javax.xml.transform.sax}, {@link javax.xml.transform.dom},
	and {@link javax.xml.transform.stream}.
	</p>


	<h3>Creating Objects</h3>

	<p>The API allows a concrete
	{@link javax.xml.transform.TransformerFactory} object to be created from
	the static function
	{@link javax.xml.transform.TransformerFactory#newInstance}.
	</p>


	<h3>Specification of Inputs and Outputs</h3>

	<p>This API defines two interface objects called
	{@link javax.xml.transform.Source} and
	{@link javax.xml.transform.Result}. In order to pass Source and Result
	objects to the interfaces, concrete classes must be used.
	Three concrete representations are defined for each of these
	objects:
	{@link javax.xml.transform.stream.StreamSource} and
	{@link javax.xml.transform.stream.StreamResult},
	{@link javax.xml.transform.sax.SAXSource} and
	{@link javax.xml.transform.sax.SAXResult}, and
	{@link javax.xml.transform.dom.DOMSource} and
	{@link javax.xml.transform.dom.DOMResult}. Each of these objects defines
	a FEATURE string (which is i the form of a URL), which can be passed into
	{@link javax.xml.transform.TransformerFactory#getFeature} to see if the
	given type of Source or Result object is supported. For instance, to test if a
	DOMSource and a StreamResult is supported, you can apply the following
	test.
	</p>

	<pre>
	<code>
	TransformerFactory tfactory = TransformerFactory.newInstance();
	if (tfactory.getFeature(DOMSource.FEATURE) && tfactory.getFeature(StreamResult.FEATURE)) {
	...
	}
	</code>
	</pre>


	<h3>
	<a name="qname-delimiter">Qualified Name Representation</a>
	</h3>

	<p><a href="http://www.w3.org/TR/REC-xml-names">Namespaces</a>
	present something of a problem area when dealing with XML objects. Qualified
	Names appear in XML markup as prefixed names. But the prefixes themselves do
	not hold identity. Rather, it is the URIs that they contextually map to that
	hold the identity. Therefore, when passing a Qualified Name like "xyz:foo"
	among Java programs, one must provide a means to map "xyz" to a namespace.
	</p>

	<p>One solution has been to create a "QName" object that holds the
	namespace URI, as well as the prefix and local name, but this is not always an
	optimal solution, as when, for example, you want to use unique strings as keys
	in a dictionary object. Not having a string representation also makes it
	difficult to specify a namespaced identity outside the context of an XML
	document.
	</p>

	<p>In order to pass namespaced values to transformations,
	for
	instance when setting a property or a parameter on a
	{@link javax.xml.transform.Transformer} object,
	this specification defines that a
	String "qname" object parameter be passed as two-part string, the namespace URI
	enclosed in curly braces ({}), followed by the local name. If the qname has a
	null URI, then the String object only contains 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.
	</p>

	<p>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 the prefix is lost.
	</p>


	<h3>Result Tree Serialization</h3>

	<p>Serialization of the result tree to a stream can be controlled with
	the {@link javax.xml.transform.Transformer#setOutputProperties} and the
	{@link javax.xml.transform.Transformer#setOutputProperty} methods.
	These properties only apply to stream results, they have no effect when
	the result is a DOM tree or SAX event stream.</p>

	<p>Strings that match the <a href="http://www.w3.org/TR/xslt#output">XSLT
	specification for xsl:output attributes</a> can be referenced from the
	{@link javax.xml.transform.OutputKeys} class. Other strings can be
	specified as well.
	If the transformer does not recognize an output key, a
	{@link java.lang.IllegalArgumentException} is thrown, unless the
	key name is <a href="#qname-delimiter">namespace qualified</a>. Output key names
	that are namespace qualified are always allowed, although they may be
	ignored by some implementations.</p>

	<p>If all that is desired is the simple identity transformation of a
	source to a result, then {@link javax.xml.transform.TransformerFactory}
	provides a
	{@link javax.xml.transform.TransformerFactory#newTransformer()} method
	with no arguments. This method creates a Transformer that effectively copies
	the source to the result. This method may be used to create a DOM from SAX
	events or to create an XML or HTML stream from a DOM or SAX events. </p>

	<h3>Exceptions and Error Reporting</h3>

	<p>The transformation API throw three types of specialized exceptions. A
	{@link javax.xml.transform.TransformerFactoryConfigurationError} is parallel to
	the {@link javax.xml.parsers.FactoryConfigurationError}, and is thrown
	when a configuration problem with the TransformerFactory exists. This error
	will typically be thrown when the transformation factory class specified with
	the "javax.xml.transform.TransformerFactory" system property cannot be found or
	instantiated.</p>

	<p>A {@link javax.xml.transform.TransformerConfigurationException}
	may be thrown if for any reason a Transformer can not be created. A
	TransformerConfigurationException may be thrown if there is a syntax error in
	the transformation instructions, for example when
	{@link javax.xml.transform.TransformerFactory#newTransformer} is
	called.</p>

	<p>{@link javax.xml.transform.TransformerException} is a general
	exception that occurs during the course of a transformation. A transformer
	exception may wrap another exception, and if any of the
	{@link javax.xml.transform.TransformerException#printStackTrace()}
	methods are called on it, it will produce a list of stack dumps, starting from
	the most recent. The transformer exception also provides a
	{@link javax.xml.transform.SourceLocator} object which indicates where
	in the source tree or transformation instructions the error occurred.
	{@link javax.xml.transform.TransformerException#getMessageAndLocation()}
	may be called to get an error message with location info, and
	{@link javax.xml.transform.TransformerException#getLocationAsString()}
	may be called to get just the location string.</p>

	<p>Transformation warnings and errors are sent to an
	{@link javax.xml.transform.ErrorListener}, at which point the
	application may decide to report the error or warning, and may decide to throw
	an <code>Exception</code> for a non-fatal error. The <code>ErrorListener</code> may be set via
	{@link javax.xml.transform.TransformerFactory#setErrorListener} for
	reporting errors that have to do with syntax errors in the transformation
	instructions, or via
	{@link javax.xml.transform.Transformer#setErrorListener} to report
	errors that occur during the transformation. The <code>ErrorListener</code> on both objects
	will always be valid and non-<code>null</code>, whether set by the application or a default
	implementation provided by the processor.
	The default implementation provided by the processor will report all warnings and errors to <code>System.err</code>
	and does not throw any <code>Exception</code>s.
	Applications are <em>strongly</em> encouraged to register and use
	<code>ErrorListener</code>s that insure proper behavior for warnings and
	errors.
	</p>


	<h3>Resolution of URIs within a transformation</h3>

	<p>The API provides a way for URIs referenced from within the stylesheet
	instructions or within the transformation to be resolved by the calling
	application. This can be done by creating a class that implements the
	{@link javax.xml.transform.URIResolver} interface, with its one method,
	{@link javax.xml.transform.URIResolver#resolve}, and use this class to
	set the URI resolution for the transformation instructions or transformation
	with {@link javax.xml.transform.TransformerFactory#setURIResolver} or
	{@link javax.xml.transform.Transformer#setURIResolver}. The
	<code>URIResolver.resolve</code> method takes two String arguments, the URI found in the
	stylesheet instructions or built as part of the transformation process, and the
	base URI
	against which the first argument will be made absolute if the
	absolute URI is required.
	The returned {@link javax.xml.transform.Source} object must be usable by
	the transformer, as specified in its implemented features.</p>


	</body>
	</html>