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This package defines the generic APIs for processing transformation instructions, and performing a transformation from source to result.
See:
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. The API achieves this by defining To define concrete classes for the user, the API defines specializations of the interfaces found at the root level. These interfaces are found in Creating ObjectsThe API allows a concrete the static function factory implementation to instantiate. This property names a concrete subclass of the TransformerFactory abstract class. If this system property is not defined, a platform default is used. Specification of Inputs and OutputsThis API defines two interface objects called objects to the interfaces, concrete classes must be used. The transformation API defines three concrete representations for each of these objects: a FEATURE string (which is i the form of a URL), which can be passed into 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.
Qualified Name representationpresent 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. 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. In order to pass namespaced values to transformations, for instance as a set of properties to the Serializer, 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. For example, if a URI and local name were obtained from an element then the transformation API Qualified Name would be "{http://xyz.foo.com/yada/baz.html}foo". Note that the prefix is lost. Result Tree SerializationSerialization of the result tree to a stream can be controlled with
Strings that match the XSLT
specification for xsl:output attributes can be referenced from the
specified as well. If the transformer does not recognize an output key, a
If all that is desired is the simple identity transformation of a provides a 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. Exceptions and Error ReportingThe transformation API throws three types of specialized exceptions. A when a configuration problem with the TransformerFactory exists. This error will typically be thrown when the transformation factory class specified with instantiated. 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 called. exception that occurs during the course of a transformation. A transformer exception may wrap another exception, and if any of the methods are called on it, it will produce a list of stack dumps, starting from the most recent. The transformer exception also provides a in the source tree or transformation instructions the error occurred. may be called to get an error message with location info, and may be called to get just the location string.Transformation warnings and errors are normally first sent to a implementor may decide to report the error or warning, and may decide to throw an exception for a non-fatal error. The error listener may be set via reporting errors that have to do with syntax errors in the transformation instructions, or via errors that occur during the transformation. The error listener on both objects should always be valid and non-null, whether set by the user or a default implementation provided by the processor. Resolution of URIs within a transformationThe 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 URIResolver interface, with its one method, set the URI resolution for the transformation instructions or transformation URIResolver.resolve method takes two String arguments, the URI found in the stylesheet instructions or built as part of the transformation process, and the base URI in effect when the URI passed as the first argument was encountered. the transformer, as specified in its implemented features.
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