fop/src/java/org/apache/fop/render/rtf/rtflib/rtfdoc/ParagraphKeeptogetherContext.java

/*
 * $Id$
 * ============================================================================
 *                    The Apache Software License, Version 1.1
 * ============================================================================
 *
 * Copyright (C) 1999-2003 The Apache Software Foundation. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modifica-
 * tion, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * 3. The end-user documentation included with the redistribution, if any, must
 *    include the following acknowledgment: "This product includes software
 *    developed by the Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself, if
 *    and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "FOP" and "Apache Software Foundation" must not be used to
 *    endorse or promote products derived from this software without prior
 *    written permission. For written permission, please contact
 *    apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache", nor may
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 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
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 * APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
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 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ============================================================================
 *
 * This software consists of voluntary contributions made by many individuals
 * on behalf of the Apache Software Foundation and was originally created by
 * James Tauber <jtauber@jtauber.com>. For more information on the Apache
 * Software Foundation, please see <http://www.apache.org/>.
 */

/*
 * This file is part of the RTF library of the FOP project, which was originally
 * created by Bertrand Delacretaz <bdelacretaz@codeconsult.ch> and by other
 * contributors to the jfor project (www.jfor.org), who agreed to donate jfor to
 * the FOP project.
 */

package org.apache.fop.render.rtf.rtflib.rtfdoc;

/**
 *
 *     This context is used to manage the "keepn" RTF attribute
 *  Used by ParagraphBuilder and JforCmd
 *
 */

public class ParagraphKeeptogetherContext {

    private static int paraKeepTogetherOpen = 0;
    private static boolean paraResetProperties = false;
    private static ParagraphKeeptogetherContext instance = null;

    ParagraphKeeptogetherContext() {
    }


    /**
     * Singelton.
     *
     * @return The instance of ParagraphKeeptogetherContext
     */
    public static ParagraphKeeptogetherContext getInstance() {
        if (instance == null) {
            instance = new ParagraphKeeptogetherContext();
        }
        return instance;
    }

    /**
     *  @return the level of current "keep whith next" paragraph
     */
    public static int getKeepTogetherOpenValue() {
        return paraKeepTogetherOpen;
    }

    /** Open a new "keep with next" paragraph */
    public static void keepTogetherOpen() {
        paraKeepTogetherOpen++;
    }

    /** Close a "keep with next" paragraph */
    public static void keepTogetherClose() {
        if (paraKeepTogetherOpen > 0) {
            paraKeepTogetherOpen--;

            //If the \pard control word is not present, the current paragraph
            //inherits all paragraph properties.
            //Also the next paragraph must reset the properties otherwise the \keepn don't stop.
            paraResetProperties = (paraKeepTogetherOpen == 0);
        }
    }

    /**
     * @return true if the next paragraph must reset the properties
     */
    public static boolean paragraphResetProperties() {
        return paraResetProperties;
    }

    /** Reset the flag if the paragraph properties have been resested */
    public static void setParagraphResetPropertiesUsed() {
        paraResetProperties = false;
    }

}