* A {@link ValidatorHandler} object is a thread-unsafe, non-reentrant object. * In other words, it is the application's responsibility to make * sure that one {@link ValidatorHandler} object is not used from * more than one thread at any given time. * *
* {@link ValidatorHandler} checks if the SAX events follow * the set of constraints described in the associated {@link Schema}, * and additionally it may modify the SAX events (for example * by adding default values, etc.) * *
* {@link ValidatorHandler} extends from {@link ContentHandler}, * but it refines the underlying {@link ContentHandler} in * the following way: *
uri, localName, and qname,
* even though SAX allows some of them to be null.
* Similarly, the user-specified {@link ContentHandler} will receive non-null
* Strings for all three parameters.
*
* * A {@link ValidatorHandler} is automatically reset every time * the startDocument method is invoked. * *
* This spec defines the following feature that must be recognized * by all {@link ValidatorHandler} implementations. * *
http://xml.org/sax/features/namespace-prefixes
* This feature controls how a {@link ValidatorHandler} introduces
* namespace bindings that were not present in the original SAX event
* stream.
* When this feature is set to true, it must make
* sure that the user's {@link ContentHandler} will see
* the corresponding xmlns* attribute in
* the {@link org.xml.sax.Attributes} object of the
* {@link ContentHandler#startElement(String,String,String,Attributes)}
* callback. Otherwise, xmlns* attributes must not be
* added to {@link org.xml.sax.Attributes} that's passed to the
* user-specified {@link ContentHandler}.
*
* (Note that regardless of this switch, namespace bindings are * always notified to applications through * {@link ContentHandler#startPrefixMapping(String,String)} and * {@link ContentHandler#endPrefixMapping(String)} methods of the * {@link ContentHandler} specified by the user.) * *
* Note that this feature does NOT affect the way * a {@link ValidatorHandler} receives SAX events. It merely * changes the way it augments SAX events. * *
This feature is set to false by default.
* The constructor does nothing. * *
* Derived classes must create {@link ValidatorHandler} objects that have * null {@link ErrorHandler} and * null {@link LSResourceResolver}. */ protected ValidatorHandler() { } /** * Sets the {@link ContentHandler} which receives * the augmented validation result. * *
* When a {@link ContentHandler} is specified, a * {@link ValidatorHandler} will work as a filter * and basically copy the incoming events to the * specified {@link ContentHandler}. * *
* In doing so, a {@link ValidatorHandler} may modify * the events, for example by adding defaulted attributes. * *
* A {@link ValidatorHandler} may buffer events to certain * extent, but to allow {@link ValidatorHandler} to be used * by a parser, the following requirement has to be met. * *
* When a callback method on the specified {@link ContentHandler} * throws an exception, the same exception object must be thrown * from the {@link ValidatorHandler}. The {@link ErrorHandler} * should not be notified of such an exception. * *
* This method can be called even during a middle of a validation. * * @param receiver * A {@link ContentHandler} or a null value. */ public abstract void setContentHandler(ContentHandler receiver); /** * Gets the {@link ContentHandler} which receives the * augmented validation result. * * @return * This method returns the object that was last set through * the {@link #getContentHandler()} method, or null * if that method has never been called since this {@link ValidatorHandler} * has created. * * @see #setContentHandler(ContentHandler) */ public abstract ContentHandler getContentHandler(); /** * Sets the {@link ErrorHandler} to receive errors encountered * during the validation. * *
* Error handler can be used to customize the error handling process * during a validation. When an {@link ErrorHandler} is set, * errors found during the validation will be first sent * to the {@link ErrorHandler}. * *
* The error handler can abort further validation immediately * by throwing {@link org.xml.sax.SAXException} from the handler. Or for example * it can print an error to the screen and try to continue the * validation by returning normally from the {@link ErrorHandler} * *
* If any {@link Throwable} is thrown from an {@link ErrorHandler}, * the same {@link Throwable} object will be thrown toward the * root of the call stack. * *
* {@link ValidatorHandler} is not allowed to * throw {@link org.xml.sax.SAXException} without first reporting it to * {@link ErrorHandler}. * *
* When the {@link ErrorHandler} is null, the implementation will * behave as if the following {@link ErrorHandler} is set: *
* class DraconianErrorHandler implements {@link ErrorHandler} {
* public void fatalError( {@link org.xml.sax.SAXParseException} e ) throws {@link org.xml.sax.SAXException} {
* throw e;
* }
* public void error( {@link org.xml.sax.SAXParseException} e ) throws {@link org.xml.sax.SAXException} {
* throw e;
* }
* public void warning( {@link org.xml.sax.SAXParseException} e ) throws {@link org.xml.sax.SAXException} {
* // noop
* }
* }
*
*
* * When a new {@link ValidatorHandler} object is created, initially * this field is set to null. * * @param errorHandler * A new error handler to be set. This parameter can be null. */ public abstract void setErrorHandler(ErrorHandler errorHandler); /** * Gets the current {@link ErrorHandler} set to this {@link ValidatorHandler}. * * @return * This method returns the object that was last set through * the {@link #setErrorHandler(ErrorHandler)} method, or null * if that method has never been called since this {@link ValidatorHandler} * has created. * * @see #setErrorHandler(ErrorHandler) */ public abstract ErrorHandler getErrorHandler(); /** * Sets the {@link LSResourceResolver} to customize * resource resolution while in a validation episode. * *
* {@link ValidatorHandler} uses a {@link LSResourceResolver} * when it needs to locate external resources while a validation, * although exactly what constitutes "locating external resources" is * up to each schema language. * *
* When the {@link LSResourceResolver} is null, the implementation will * behave as if the following {@link LSResourceResolver} is set: *
* class DumbLSResourceResolver implements {@link LSResourceResolver} {
* public {@link org.w3c.dom.ls.LSInput} resolveResource(
* String publicId, String systemId, String baseURI) {
*
* return null; // always return null
* }
* }
*
*
*
* If a {@link LSResourceResolver} throws a {@link RuntimeException}
* (or instances of its derived classes),
* then the {@link ValidatorHandler} will abort the parsing and
* the caller of the validate method will receive
* the same {@link RuntimeException}.
*
*
* When a new {@link ValidatorHandler} object is created, initially * this field is set to null. * * @param resourceResolver * A new resource resolver to be set. This parameter can be null. */ public abstract void setResourceResolver(LSResourceResolver resourceResolver); /** * Gets the current {@link LSResourceResolver} set to this {@link ValidatorHandler}. * * @return * This method returns the object that was last set through * the {@link #setResourceResolver(LSResourceResolver)} method, or null * if that method has never been called since this {@link ValidatorHandler} * has created. * * @see #setErrorHandler(ErrorHandler) */ public abstract LSResourceResolver getResourceResolver(); /** * Obtains the {@link TypeInfoProvider} implementation of this * {@link ValidatorHandler}. * *
* The obtained {@link TypeInfoProvider} can be queried during a parse * to access the type information determined by the validator. * *
* Some schema languages do not define the notion of type, * for those languages, this method may not be supported. * However, to be compliant with this specification, implementations * for W3C XML Schema 1.0 must support this operation. * * @return * null if the validator / schema language does not support * the notion of {@link org.w3c.dom.TypeInfo}. * Otherwise a non-null valid {@link TypeInfoProvider}. */ public abstract TypeInfoProvider getTypeInfoProvider(); /** * Look up the value of a feature flag. * *
The feature name is any fully-qualified URI. It is * possible for a {@link ValidatorHandler} to recognize a feature name but * temporarily be unable to return its value. * Some feature values may be available only in specific * contexts, such as before, during, or after a validation. * *
Implementors are free (and encouraged) to invent their own features, * using names built on their own URIs.
* * @param name The feature name, which is a non-null fully-qualified URI. * @return The current value of the feature (true or false). * @exception org.xml.sax.SAXNotRecognizedException If the feature * value can't be assigned or retrieved. * @exception org.xml.sax.SAXNotSupportedException When the * {@link ValidatorHandler} recognizes the feature name but * cannot determine its value at this time. * @throws NullPointerException * When the name parameter is null. * @see #setFeature(String, boolean) */ public boolean getFeature(String name) throws SAXNotRecognizedException, SAXNotSupportedException { if(name==null) throw new NullPointerException(); throw new SAXNotRecognizedException(name); } /** * Set the value of a feature flag. * ** Feature can be used to control the way a {@link ValidatorHandler} * parses schemas, although {@link ValidatorHandler}s are not required * to recognize any specific property names.
* *The feature name is any fully-qualified URI. It is * possible for a {@link ValidatorHandler} to expose a feature value but * to be unable to change the current value. * Some feature values may be immutable or mutable only * in specific contexts, such as before, during, or after * a validation.
* * @param name The feature name, which is a non-null fully-qualified URI. * @param value The requested value of the feature (true or false). * * @exception org.xml.sax.SAXNotRecognizedException If the feature * value can't be assigned or retrieved. * @exception org.xml.sax.SAXNotSupportedException When the * {@link ValidatorHandler} recognizes the feature name but * cannot set the requested value. * @throws NullPointerException * When the name parameter is null. * * @see #getFeature(String) */ public void setFeature(String name, boolean value) throws SAXNotRecognizedException, SAXNotSupportedException { if(name==null) throw new NullPointerException(); throw new SAXNotRecognizedException(name); } /** * Set the value of a property. * *The property name is any fully-qualified URI. It is * possible for a {@link ValidatorHandler} to recognize a property name but * to be unable to change the current value. * Some property values may be immutable or mutable only * in specific contexts, such as before, during, or after * a validation.
* *{@link ValidatorHandler}s are not required to recognize setting * any specific property names.
* * @param name The property name, which is a non-null fully-qualified URI. * @param object The requested value for the property. * * @exception org.xml.sax.SAXNotRecognizedException If the property * value can't be assigned or retrieved. * @exception org.xml.sax.SAXNotSupportedException When the * {@link ValidatorHandler} recognizes the property name but * cannot set the requested value. * @throws NullPointerException * When the name parameter is null. */ public void setProperty(String name, Object object) throws SAXNotRecognizedException, SAXNotSupportedException { if(name==null) throw new NullPointerException(); throw new SAXNotRecognizedException(name); } /** * Look up the value of a property. * *The property name is any fully-qualified URI. It is * possible for a {@link ValidatorHandler} to recognize a property name but * temporarily be unable to return its value. * Some property values may be available only in specific * contexts, such as before, during, or after a validation.
* *{@link ValidatorHandler}s are not required to recognize any specific * property names.
* *Implementors are free (and encouraged) to invent their own properties, * using names built on their own URIs.
* * @param name The property name, which is a non-null fully-qualified URI. * @return The current value of the property. * @exception org.xml.sax.SAXNotRecognizedException If the property * value can't be assigned or retrieved. * @exception org.xml.sax.SAXNotSupportedException When the * XMLReader recognizes the property name but * cannot determine its value at this time. * @throws NullPointerException * When the name parameter is null. * @see #setProperty(String, Object) */ public Object getProperty(String name) throws SAXNotRecognizedException, SAXNotSupportedException { if(name==null) throw new NullPointerException(); throw new SAXNotRecognizedException(name); } }