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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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 * 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,

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package org.xml.sax;

/**

 * Interface for an XML filter.

 *

 * <p>An XML filter is like an XML reader, except that it obtains its

 * events from another XML reader rather than a primary source like

 * an XML document or database.  Filters can modify a stream of

 * events as they pass on to the final application.</p>

 *

 * <p>The XMLFilterImpl helper class provides a convenient base

 * for creating SAX2 filters, by passing on all {@link org.xml.sax.EntityResolver

 * EntityResolver}, {@link org.xml.sax.DTDHandler DTDHandler},

 * {@link org.xml.sax.ContentHandler ContentHandler} and {@link org.xml.sax.ErrorHandler

 * ErrorHandler} events automatically.</p>

 *

 * @since 1.4, SAX 2.0

 * @author David Megginson

 * @see org.xml.sax.helpers.XMLFilterImpl

 */

public interface XMLFilter extends XMLReader

{

    /**

     * Set the parent reader.

     *

     * <p>This method allows the application to link the filter to

     * a parent reader (which may be another filter).  The argument

     * may not be null.</p>

     *

     * @param parent The parent reader.

     */

    public abstract void setParent (XMLReader parent);

    /**

     * Get the parent reader.

     *

     * <p>This method allows the application to query the parent

     * reader (which may be another filter).  It is generally a

     * bad idea to perform any operations on the parent reader

     * directly: they should all pass through this filter.</p>

     *

     * @return The parent filter, or null if none has been set.

     */

    public abstract XMLReader getParent ();

}

// end of XMLFilter.java