org.opengis.cite.validation

Class XmlSchemaCompiler

java.lang.Object

org.opengis.cite.validation.XmlSchemaCompiler

public class XmlSchemaCompiler
extends Object

Provides various convenience methods for compiling W3C XML schemas and creating a thread-safe Schema object: an immutable in-memory representation of one or more grammars spanning one or more target namespaces. An OASIS entity catalog is used to resolve schema references. Note that, in general, the top-level schema entity is never passed to the LSResourceResolver object set on a SchemaFactory. However an instance of this class will use the catalog to resolve the given URI reference, thus enabling redirection to a local copy of the schema. If a matching entry (system id or namespace name) is not found, a regular URI connection to the resource should be established.

See Also:

XML Catalogs, v1.1

Constructor Summary

Constructors

Constructor and Description
XmlSchemaCompiler(URL catalog) Constructs and configures an XmlSchemaCompiler to use an OASIS entity catalog to resolve schema references.

Method Summary

Modifier and Type	Method and Description
Schema	compileXmlSchema(Source... xsdSources) Compiles a sequence of W3C XML Schema resources that may be used to perform grammar-based validation of an XML instance.
Schema	compileXmlSchema(URI... schemaURIs) Compiles W3C XML Schema resources obtained from the specified sequence of URI references.
(package private) File	dereferenceURI(URI schemaURI) Dereferences the given URI and writes the resulting entity (XML Schema) to a local file.
ValidationErrorHandler	getErrorHandler() Returns the specialized error handler used to collect all errors encountered while parsing schemas.
(package private) String	lookupSchemaByURI(URI uri) Looks up a (schema) URI in an entity catalog by system identifier or namespace name.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

XmlSchemaCompiler

public XmlSchemaCompiler(URL catalog)

Constructs and configures an XmlSchemaCompiler to use an OASIS entity catalog to resolve schema references.

Parameters:

catalog - An absolute URL specifying the location of an OASIS entity catalog.

Method Detail

getErrorHandler

public ValidationErrorHandler getErrorHandler()

Returns the specialized error handler used to collect all errors encountered while parsing schemas. The error handler is reset before a new Schema object is constructed.

Returns:

A ValidationErrorHandler object recording the status of the last attempt to compile a schema.

compileXmlSchema

public Schema compileXmlSchema(URI... schemaURIs)
                        throws SAXException,
                               IOException

Compiles W3C XML Schema resources obtained from the specified sequence of URI references. The resulting schema contains components from the specified sources. An attempt will be made to first resolve a schema URI using the entity catalog; if that fails a normal connection to the resource will be established to retrieve it.

Parameters:

schemaURIs - A sequence (or array) of absolute URIs representing schema locations.

Returns:

A thread-safe, composite Schema object or null if compilation failed for any reason.

Throws:

SAXException - If an error occurs while attempting to read a schema.

IOException - If an error occurs while attempting to retrieve a schema.

compileXmlSchema

public Schema compileXmlSchema(Source... xsdSources)
                        throws SAXException

Compiles a sequence of W3C XML Schema resources that may be used to perform grammar-based validation of an XML instance. The resulting schema contains components from the specified sources. Check the error handler for any problems that were detected; these might arise even if the schema was successfully compiled.

Parameters:

xsdSources - A sequence (or array) of Source objects used to read the input schemas.

Returns:

A thread-safe, composite Schema object or null if compilation failed for any reason.

Throws:

SAXException - If an error occurs while attempting to compile the schema (e.g. it's malformed).

lookupSchemaByURI

String lookupSchemaByURI(URI uri)

Looks up a (schema) URI in an entity catalog by system identifier or namespace name.

Parameters:

uri - An absolute URI referring to an XML Schema resource.

Returns:

A String denoting the location of a local copy, or null if no matching entry exists.

dereferenceURI

File dereferenceURI(URI schemaURI)
             throws IOException

Dereferences the given URI and writes the resulting entity (XML Schema) to a local file. If a communications link cannot be established within 5 s, a java.net.SocketTimeoutException is raised.

Parameters:

schemaURI - An absolute URI reference.

Returns:

A File object containing the referenced entity; it is located in the default temporary-file directory.

Throws:

IOException - If the resource cannot be retrieved.