/* ====================================================================   Copyright 2002-2004   Apache Software Foundation   Licensed 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.==================================================================== */        package org.apache.poi.hpsf;import java.io.InputStream;import java.io.IOException;import java.io.UnsupportedEncodingException;import java.rmi.UnexpectedException;/** * <p>Factory class to create instances of {@link SummaryInformation}, * {@link DocumentSummaryInformation} and {@link PropertySet}.</p> * * @author Rainer Klute <a * href="mailto:klute@rainer-klute.de">&lt;klute@rainer-klute.de&gt;</a> * @version $Id: PropertySetFactory.java,v 1.12 2004/06/22 16:11:39 klute Exp $ * @since 2002-02-09 */public class PropertySetFactory{    /**     * <p>Creates the most specific {@link PropertySet} from an {@link     * InputStream}. This is preferrably a {@link     * DocumentSummaryInformation} or a {@link SummaryInformation}. If     * the specified {@link InputStream} does not contain a property     * set stream, an exception is thrown and the {@link InputStream}     * is repositioned at its beginning.</p>     *     * @param stream Contains the property set stream's data.     * @return The created {@link PropertySet}.     * @throws NoPropertySetStreamException if the stream does not     * contain a property set.     * @throws MarkUnsupportedException if the stream does not support     * the <code>mark</code> operation.     * @throws IOException if some I/O problem occurs.     * @exception UnsupportedEncodingException if the specified codepage is not     * supported.     */    public static PropertySet create(final InputStream stream)        throws NoPropertySetStreamException, MarkUnsupportedException,               UnsupportedEncodingException, IOException    {        final PropertySet ps = new PropertySet(stream);        try        {            if (ps.isSummaryInformation())                return new SummaryInformation(ps);            else if (ps.isDocumentSummaryInformation())                return new DocumentSummaryInformation(ps);            else                return ps;        }        catch (UnexpectedPropertySetTypeException ex)        {            /* This exception will never be throws because we already checked             * explicitly for this case above. */            throw new UnexpectedException(ex.toString());        }    }}