fop/src/java/org/apache/fop/render/rtf/rtflib/tools/ImageUtil.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
 *    "Apache" appear in their name, without prior written permission of the
 *    Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU-
 * DING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * 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.tools;

/**  Misc.utilities for images handling
 *  This class belongs to the <fo:external-graphic> tag processing.
 *  @author <a href="mailto:a.putz@skynamics.com">Andreas Putz</a>
 */
public class ImageUtil {

    //////////////////////////////////////////////////
    // @@ Construction
    //////////////////////////////////////////////////

    /**
     * Private constructor.
     */
    private ImageUtil () {
    }


    //////////////////////////////////////////////////
    // @@ Public static methods
    //////////////////////////////////////////////////

    /**
     * Determines the digits from a string.
     *
     * @param value String with digits
     *
     * @return -1      There is no digit
     *         number  The digits as integer
     */
    public static int getInt (String value) {
        String retString = new String ();
        StringBuffer s = new StringBuffer (value);
        int len = s.length ();

        for (int i = 0; i < len; i++) {
            if (Character.isDigit (s.charAt (i))) {
                retString += s.charAt (i);
            }
        }

        if (retString.length () == 0) {
            return -1;
        } else {
            return Integer.parseInt (retString);
        }
    }

    /**
     * Checks the string for percent character at the end of string.
     *
     * @param value String with digits
     *
     * @return true    The string contains a % value
     *         false   Other string
     */
    public static boolean isPercent (String value) {
        if (value.endsWith ("%")) {
            return true;

        }

        return false;
    }

    /**
     * Compares two hexadecimal values.
     *
     * @param pattern Target
     * @param data Data
     * @param searchAt Position to start compare
     * @param searchForward Direction to compare byte arrays
     *
     * @return true    If equal
     *         false   If different
     */
    public static boolean compareHexValues (byte[] pattern, byte[] data, int searchAt,
                                            boolean searchForward) {
        if (searchAt >= data.length) {
            return false;

        }

        int pLen = pattern.length;

        if (searchForward) {
            if (pLen >= (data.length - searchAt)) {
                return false;

            }

            for (int i = 0; i < pLen; i++) {
                if (pattern[i] != data[searchAt + i]) {
                    return false;
                }
            }

            return true;
        } else {
            if (pLen > (searchAt + 1)) {
                return false;

            }

            for (int i = 0; i < pLen; i++) {
                if (pattern[pLen - i - 1] != data[searchAt - i]) {
                    return false;
                }
            }

            return true;
        }
    }

    /**
     * Determines a integer value from a hexadecimal byte array.
     *
     * @param data Image
     * @param startAt Start index to read from
     * @param length Number of data elements to read
     * @param searchForward True if searching forward, False if not (??)
     *
     * @return integer
     */
    public static int getIntFromByteArray (byte[] data, int startAt, int length,
                                           boolean searchForward) {
        int bit = 8;
        int bitMoving = length * bit;
        int retVal = 0;

        if (startAt >= data.length) {
            return retVal;

        }

        if (searchForward) {
            if (length >= (data.length - startAt)) {
                return retVal;

            }

            for (int i = 0; i < length; i++) {
                bitMoving -= bit;
                int iData = (int) data[startAt + i];
                if (iData < 0) {
                    iData += 256;
                }
                retVal += iData << bitMoving;
            }
        } else {
            if (length > (startAt + 1)) {
                return retVal;

            }

            for (int i = 0; i < length; i++) {
                bitMoving -= bit;
                int iData = (int) data[startAt - i];
                if (iData < 0) {
                    iData += 256;
                }
                retVal += iData << bitMoving;            }
        }

        return retVal;
    }
}