/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// $Id: Validator.java 888884 2009-12-09 17:36:46Z mrglavas $
package javax.xml.validation;
import java.io.IOException;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import org.w3c.dom.ls.LSResourceResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.SAXException;
import org.xml.sax.SAXNotRecognizedException;
import org.xml.sax.SAXNotSupportedException;
/**
* <p>A processor that checks an XML document against {@link Schema}.</p>
*
* <p>
* A validator is a thread-unsafe and non-reentrant object.
* In other words, it is the application's responsibility to make
* sure that one {@link Validator} object is not used from
* more than one thread at any given time, and while the <tt>validate</tt>
* method is invoked, applications may not recursively call
* the <tt>validate</tt> method.
* <p>
*
* Note that while the {@link #validate(javax.xml.transform.Source)} and {@link #validate(javax.xml.transform.Source, javax.xml.transform.Result)}
* methods take a {@link Source} instance, the <code>Source</code>
* instance must be a <code>SAXSource</code>, <code>DOMSource</code>, <code>StAXSource</code> or <code>StreamSource</code>.
*
* @author <a href="mailto:Kohsuke.Kawaguchi@Sun.com">Kohsuke Kawaguchi</a>
* @version $Revision: 888884 $, $Date: 2009-12-09 09:36:46 -0800 (Wed, 09 Dec 2009) $
* @since 1.5
*/
public abstract class Validator {
/**
* Constructor for derived classes.
*
* <p>
* The constructor does nothing.
*
* <p>
* Derived classes must create {@link Validator} objects that have
* <tt>null</tt> {@link ErrorHandler} and
* <tt>null</tt> {@link LSResourceResolver}.
*/
protected Validator() {
}
/**
* <p>Reset this <code>Validator</code> to its original configuration.</p>
*
* <p><code>Validator</code> is reset to the same state as when it was created with
* {@link Schema#newValidator()}.
* <code>reset()</code> is designed to allow the reuse of existing <code>Validator</code>s
* thus saving resources associated with the creation of new <code>Validator</code>s.</p>
*
* <p>The reset <code>Validator</code> is not guaranteed to have the same {@link LSResourceResolver} or {@link ErrorHandler}
* <code>Object</code>s, e.g. {@link Object#equals(Object obj)}. It is guaranteed to have a functionally equal
* <code>LSResourceResolver</code> and <code>ErrorHandler</code>.</p>
*/
public abstract void reset();
/**
* Validates the specified input.
*
* <p>
* This is just a convenience method of:
* <pre>
* validate(source,null);
* </pre>
*
* @see #setErrorHandler(ErrorHandler)
*/
public void validate(Source source) throws SAXException, IOException {
validate(source, null);
}
/**
* Validates the specified input and send the augmented validation
* result to the specified output.
*
* <p>
* This method places the following restrictions on the types of
* the {@link Source}/{@link Result} accepted.
*
* <h4>{@link Source}/{@link Result} accepted:</h4>
* <table border=1>
* <thead>
* <tr>
* <td></td>
* <td>{@link javax.xml.transform.sax.SAXSource}</td>
* <td>{@link javax.xml.transform.dom.DOMSource}</td>
* <td>{@link javax.xml.transform.stream.StreamSource}</td>
* </tr>
* </thead>
* <tbody>
* <tr>
* <td><tt>null</tt></td>
* <td>OK</td>
* <td>OK</td>
* <td>OK</td>
* <td>OK</td>
* </tr>
* <tr>
* <td>{@link javax.xml.transform.sax.SAXResult}</td>
* <td>OK</td>
* <td>Err</td>
* <td>Err</td>
* <td>Err</td>
* </tr>
* <tr>
* <td>{@link javax.xml.transform.dom.DOMResult}</td>
* <td>Err</td>
* <td>OK</td>
* <td>Err</td>
* <td>Err</td>
* </tr>
* <tr>
* <td>{@link javax.xml.transform.stream.StreamResult}</td>
* <td>Err</td>
* <td>Err</td>
* <td>Err</td>
* <td>OK</td>
* </tr>
* </tbody>
* </table>
*
* <p>
* To validate one {@link Source} into another kind of {@link Result}, use the identity transformer
* (see {@link javax.xml.transform.TransformerFactory#newTransformer()}).
*
* <p>
* Errors found during the validation is sent to the specified
* {@link ErrorHandler}.
*
* <p>
* If a document is valid, or if a document contains some errors
* but none of them were fatal and the {@link ErrorHandler} didn't
* throw any exception, then the method returns normally.
*
* @param source
* XML to be validated. Must not be null.
*
* @param result
* The {@link Result} object that receives (possibly augmented)
* XML. This parameter can be null if the caller is not interested
* in it.
*
* Note that when a {@link javax.xml.transform.dom.DOMResult} is used,
* a validator might just pass the same DOM node from
* {@link javax.xml.transform.dom.DOMSource} to
* {@link javax.xml.transform.dom.DOMResult}
* (in which case <tt>source.getNode()==result.getNode()</tt>),
* it might copy the entire DOM tree, or it might alter the
* node given by the source.
*
* @throws IllegalArgumentException
* If the {@link Result} type doesn't match the {@link Source} type,
* or if the specified source is not a
* {@link javax.xml.transform.sax.SAXSource},
* {@link javax.xml.transform.dom.DOMSource} or
* {@link javax.xml.transform.stream.StreamSource}.
*
* @throws SAXException
* If the {@link ErrorHandler} throws a {@link SAXException} or
* if a fatal error is found and the {@link ErrorHandler} returns
* normally.
*
* @throws IOException
* If the validator is processing a
* {@link javax.xml.transform.sax.SAXSource} and the
* underlying {@link org.xml.sax.XMLReader} throws an
* {@link IOException}.
*
* @throws NullPointerException
* If the <tt>source</tt> parameter is null.
*
* @see #validate(Source)
*/
public abstract void validate(Source source, Result result) throws SAXException, IOException;
/**
* Sets the {@link ErrorHandler} to receive errors encountered
* during the <code>validate</code> method invocation.
*
* <p>
* 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}.
*
* <p>
* The error handler can abort further validation immediately
* by throwing {@link 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}
*
* <p>
* If any {@link Throwable} is thrown from an {@link ErrorHandler},
* the caller of the <code>validate</code> method will be thrown
* the same {@link Throwable} object.
*
* <p>
* {@link Validator} is not allowed to
* throw {@link SAXException} without first reporting it to
* {@link ErrorHandler}.
*
* <p>
* When the {@link ErrorHandler} is null, the implementation will
* behave as if the following {@link ErrorHandler} is set:
* <pre>
* class DraconianErrorHandler implements {@link ErrorHandler} {
* public void fatalError( {@link org.xml.sax.SAXParseException} e ) throws {@link SAXException} {
* throw e;
* }
* public void error( {@link org.xml.sax.SAXParseException} e ) throws {@link SAXException} {
* throw e;
* }
* public void warning( {@link org.xml.sax.SAXParseException} e ) throws {@link SAXException} {
* // noop
* }
* }
* </pre>
*
* <p>
* When a new {@link Validator} 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 Validator}.
*
* @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 Validator}
* has created.
*
* @see #setErrorHandler(ErrorHandler)
*/
public abstract ErrorHandler getErrorHandler();
/**
* Sets the {@link LSResourceResolver} to customize
* resource resolution while in a validation episode.
*
* <p>
* {@link Validator} 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.
*
* <p>
* When the {@link LSResourceResolver} is null, the implementation will
* behave as if the following {@link LSResourceResolver} is set:
* <pre>
* class DumbLSResourceResolver implements {@link LSResourceResolver} {
* public {@link org.w3c.dom.ls.LSInput} resolveResource(
* String publicId, String systemId, String baseURI) {
*
* return null; // always return null
* }
* }
* </pre>
*
* <p>
* If a {@link LSResourceResolver} throws a {@link RuntimeException}
* (or instances of its derived classes),
* then the {@link Validator} will abort the parsing and
* the caller of the <code>validate</code> method will receive
* the same {@link RuntimeException}.
*
* <p>
* When a new {@link Validator} 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 Validator}.
*
* @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 Validator}
* has created.
*
* @see #setErrorHandler(ErrorHandler)
*/
public abstract LSResourceResolver getResourceResolver();
/**
* Look up the value of a feature flag.
*
* <p>The feature name is any fully-qualified URI. It is
* possible for a {@link Validator} 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.
*
* <p>Implementors are free (and encouraged) to invent their own features,
* using names built on their own URIs.</p>
*
* @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 Validator} 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("name == null");
}
throw new SAXNotRecognizedException(name);
}
/**
* Set the value of a feature flag.
*
* <p>
* Feature can be used to control the way a {@link Validator}
* parses schemas, although {@link Validator}s are not required
* to recognize any specific property names.</p>
*
* <p>The feature name is any fully-qualified URI. It is
* possible for a {@link Validator} 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.</p>
*
* @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 Validator} 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("name == null");
}
throw new SAXNotRecognizedException(name);
}
/**
* Set the value of a property.
*
* <p>The property name is any fully-qualified URI. It is
* possible for a {@link Validator} 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.</p>
*
* <p>{@link Validator}s are not required to recognize setting
* any specific property names.</p>
*
* @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 Validator} 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("name == null");
}
throw new SAXNotRecognizedException(name);
}
/**
* Look up the value of a property.
*
* <p>The property name is any fully-qualified URI. It is
* possible for a {@link Validator} 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.</p>
*
* <p>{@link Validator}s are not required to recognize any specific
* property names.</p>
*
* <p>Implementors are free (and encouraged) to invent their own properties,
* using names built on their own URIs.</p>
*
* @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("name == null");
}
throw new SAXNotRecognizedException(name);
}
}