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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package javax.xml.validation;
import org.w3c.dom.TypeInfo;
/**
* This class provides access to the type information determined
* by {@link ValidatorHandler}.
*
* <p>
* Some schema languages, such as W3C XML Schema, encourages a validator
* to report the "type" it assigns to each attribute/element.
* Those applications who wish to access this type information can invoke
* methods defined on this "interface" to access such type information.
*
* <p>
* Implementation of this "interface" can be obtained through the
* {@link ValidatorHandler#getTypeInfoProvider()} method.
*
* @author <a href="mailto:Kohsuke.Kawaguchi@Sun.com">Kohsuke Kawaguchi</a>
* @see org.w3c.dom.TypeInfo
* @since 1.5
*/
public abstract class TypeInfoProvider {
/**
* Constructor for the derived class.
*
* <p>
* The constructor does nothing.
*/
protected TypeInfoProvider() {
}
/**
* <p>Returns the immutable {@link TypeInfo} object for the current
* element.</p>
*
* <p>The method may only be called by the startElement event
* or the endElement event
* of the {@link org.xml.sax.ContentHandler} that the application sets to
* the {@link ValidatorHandler}.</p>
*
* <p>When W3C XML Schema validation is being performed, in the
* case where an element has a union type, the {@link TypeInfo}
* returned by a call to <code>getElementTypeInfo()</code> from the
* startElement
* event will be the union type. The <code>TypeInfo</code>
* returned by a call
* from the endElement event will be the actual member type used
* to validate the element.</p>
*
* @throws IllegalStateException
* If this method is called from other {@link org.xml.sax.ContentHandler}
* methods.
* @return
* An immutable {@link TypeInfo} object that represents the
* type of the current element.
* Note that the caller can keep references to the obtained
* {@link TypeInfo} longer than the callback scope.
*
* Otherwise, this method returns
* null if the validator is unable to
* determine the type of the current element for some reason
* (for example, if the validator is recovering from
* an earlier error.)
*
*/
public abstract TypeInfo getElementTypeInfo();
/**
* Returns the immutable {@link TypeInfo} object for the specified
* attribute of the current element.
*
* <p>
* The method may only be called by the startElement event of
* the {@link org.xml.sax.ContentHandler} that the application sets to the
* {@link ValidatorHandler}.</p>
*
* @param index
* The index of the attribute. The same index for
* the {@link org.xml.sax.Attributes} object passed to the
* <code>startElement</code> callback.
*
* @throws IndexOutOfBoundsException
* If the index is invalid.
* @throws IllegalStateException
* If this method is called from other {@link org.xml.sax.ContentHandler}
* methods.
*
* @return
* An immutable {@link TypeInfo} object that represents the
* type of the specified attribute.
* Note that the caller can keep references to the obtained
* {@link TypeInfo} longer than the callback scope.
*
* Otherwise, this method returns
* null if the validator is unable to
* determine the type.
*/
public abstract TypeInfo getAttributeTypeInfo(int index);
/**
* Returns <code>true</code> if the specified attribute is determined
* to be ID.
*
* <p>
* Exacly how an attribute is "determined to be ID" is up to the
* schema language. In case of W3C XML Schema, this means
* that the actual type of the attribute is the built-in ID type
* or its derived type.
*
* <p>
* A {@link javax.xml.parsers.DocumentBuilder} uses this information
* to properly implement {@link org.w3c.dom.Attr#isId()}.
*
* <p>
* The method may only be called by the startElement event of
* the {@link org.xml.sax.ContentHandler} that the application sets to the
* {@link ValidatorHandler}.
*
* @param index
* The index of the attribute. The same index for
* the {@link org.xml.sax.Attributes} object passed to the
* <code>startElement</code> callback.
*
* @throws IndexOutOfBoundsException
* If the index is invalid.
* @throws IllegalStateException
* If this method is called from other {@link org.xml.sax.ContentHandler}
* methods.
*
* @return true
* if the type of the specified attribute is ID.
*/
public abstract boolean isIdAttribute(int index);
/**
* Returns <code>false</code> if the attribute was added by the validator.
*
* <p>
* This method provides information necessary for
* a {@link javax.xml.parsers.DocumentBuilder} to determine what
* the DOM tree should return from the {@link org.w3c.dom.Attr#getSpecified()} method.
*
* <p>
* The method may only be called by the startElement event of
* the {@link org.xml.sax.ContentHandler} that the application sets to the
* {@link ValidatorHandler}.
*
* <p>
* A general guideline for validators is to return true if
* the attribute was originally present in the pipeline, and
* false if it was added by the validator.
*
* @param index
* The index of the attribute. The same index for
* the {@link org.xml.sax.Attributes} object passed to the
* <code>startElement</code> callback.
*
* @throws IndexOutOfBoundsException
* If the index is invalid.
* @throws IllegalStateException
* If this method is called from other {@link org.xml.sax.ContentHandler}
* methods.
*
* @return
* <code>true</code> if the attribute was present before the validator
* processes input. <code>false</code> if the attribute was added
* by the validator.
*/
public abstract boolean isSpecified(int index);
}