+ This package provides an API for validation of XML documents. Validation is the process of verifying + that an XML document is an instance of a specified XML schema. An XML schema defines the + content model (also called a grammar or vocabulary) that its instance documents + will represent. +
++ There are a number of popular technologies available for creating an XML schema. Some of the most + popular include: +
++ Previous versions of JAXP supported validation as a feature of an XML parser, represented by + either a {@link javax.xml.parsers.SAXParser} or {@link javax.xml.parsers.DocumentBuilder} instance. +
++ The JAXP validation API decouples the validation of an instance document from the parsing of an + XML document. This is advantageous for several reasons, some of which are: +
++ Usage example. The following example demonstrates validating + an XML document with the Validation API (for readability, some exception handling is not shown): +
+
+
+ // parse an XML document into a DOM tree
+ DocumentBuilder parser = DocumentBuilderFactory.newInstance().newDocumentBuilder();
+ Document document = parser.parse(new File("instance.xml"));
+
+ // create a SchemaFactory capable of understanding WXS schemas
+ SchemaFactory factory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
+
+ // load a WXS schema, represented by a Schema instance
+ Source schemaFile = new StreamSource(new File("mySchema.xsd"));
+ Schema schema = factory.newSchema(schemaFile);
+
+ // create a Validator instance, which can be used to validate an instance document
+ Validator validator = schema.newValidator();
+
+ // validate the DOM tree
+ try {
+ validator.validate(new DOMSource(document));
+ } catch (SAXException e) {
+ // instance document is invalid!
+ }
+
+
+ The JAXP parsing API has been integrated with the Validation API. Applications may create a {@link javax.xml.validation.Schema} with the validation API
+ and associate it with a {@link javax.xml.parsers.DocumentBuilderFactory} or a {@link javax.xml.parsers.SAXParserFactory} instance
+ by using the {@link javax.xml.parsers.DocumentBuilderFactory#setSchema(Schema)} and {@link javax.xml.parsers.SAXParserFactory#setSchema(Schema)}
+ methods. You should not both set a schema and call setValidating(true) on a parser factory. The former technique
+ will cause parsers to use the new validation API; the latter will cause parsers to use their own internal validation
+ facilities. Turning on both of these options simultaneously will cause either redundant behavior or error conditions.
+