/* $Id: CascadingDataEntryWriter.java,v 1.3.2.1 2006/01/16 22:57:55 eric Exp $ * * ProGuard -- shrinking, optimization, and obfuscation of Java class files. * * Copyright (c) 2002-2006 Eric Lafortune (eric@graphics.cornell.edu) * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the Free * Software Foundation; either version 2 of the License, or (at your option) * any later version. * * This program 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 for * more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */package proguard.io;import proguard.util.*;import java.io.*;/** * This DataEntryWriter delegates to a given DataEntryWriter, or failing that, * to another given DataEntryWriter. * * @author Eric Lafortune */public class CascadingDataEntryWriter implements DataEntryWriter{    private DataEntryWriter dataEntryWriter1;    private DataEntryWriter dataEntryWriter2;    /**     * Creates a new FilteredDataEntryWriter.     * @param dataEntryWriter1 the DataEntryWriter to which the writing will be     *                         delegated first.     * @param dataEntryWriter2 the DataEntryWriter to which the writing will be     *                         delegated, if the first one can't provide an     *                         output stream.     */    public CascadingDataEntryWriter(DataEntryWriter dataEntryWriter1,                                    DataEntryWriter dataEntryWriter2)    {        this.dataEntryWriter1 = dataEntryWriter1;        this.dataEntryWriter2 = dataEntryWriter2;    }    // Implementations for DataEntryWriter.    public OutputStream getOutputStream(DataEntry dataEntry) throws IOException    {        return getOutputStream(dataEntry,  null);    }    public OutputStream getOutputStream(DataEntry dataEntry,                                        Finisher  finisher) throws IOException    {        // Try to get an output stream from the first data entry writer.        OutputStream outputStream =            dataEntryWriter1.getOutputStream(dataEntry, finisher);        // Return it, if it's not null. Otherwise try to get an output stream        // from the second data entry writer.        return outputStream != null ?            outputStream :            dataEntryWriter2.getOutputStream(dataEntry, finisher);    }    public void close() throws IOException    {        dataEntryWriter1.close();        dataEntryWriter2.close();        dataEntryWriter1 = null;        dataEntryWriter2 = null;    }}