Java tutorial
/* * * This file is part of the iText (R) project. Copyright (c) 1998-2019 iText Group NV * Authors: Pavel Mitrofanov, Bruno Lowagie, et al. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License version 3 * as published by the Free Software Foundation with the addition of the * following permission added to Section 15 as permitted in Section 7(a): * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY * ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT * OF THIRD PARTY RIGHTS. * * 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 Affero General License for more * details. You should have received a copy of the GNU Affero General License * along with this program; if not, see http://www.gnu.org/licenses or write to * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, * MA, 02110-1301 USA, or download the license from the following URL: * http://itextpdf.com/terms-of-use/ * * The interactive user interfaces in modified source and object code versions * of this program must display Appropriate Legal Notices, as required under * Section 5 of the GNU Affero General License. * * In accordance with Section 7(b) of the GNU Affero General License, a covered * work must retain the producer line in every PDF that is created or * manipulated using iText. * * You can be released from the requirements of the license by purchasing a * commercial license. Buying such a license is mandatory as soon as you develop * commercial activities involving the iText software without disclosing the * source code of your own applications. These activities include: offering paid * services to customers as an ASP, serving PDFs on the fly in a web * application, shipping iText with a closed source product. * * For more information, please contact iText Software Corp. at this address: * sales@itextpdf.com */ package com.itextpdf.text.pdf.parser; import com.itextpdf.text.pdf.PdfArray; /** * Represents the line dash pattern. The line dash pattern shall control the pattern * of dashes and gaps used to stroke paths. It shall be specified by a dash array and * a dash phase. * * @since 5.5.6 */ public class LineDashPattern { private PdfArray dashArray; private float dashPhase; private int currentIndex; private int elemOrdinalNumber = 1; private DashArrayElem currentElem; /** * Creates new {@link LineDashPattern} object. * @param dashArray The dash array. See {@link #getDashArray()} * @param dashPhase The dash phase. See {@link #getDashPhase()} */ public LineDashPattern(PdfArray dashArray, float dashPhase) { this.dashArray = new PdfArray(dashArray); this.dashPhase = dashPhase; initFirst(dashPhase); } /** * Getter for the dash array. * * The dash arrays elements is number that specify the lengths of * alternating dashes and gaps; the numbers are nonnegative. The * elements are expressed in user space units. * * @return The dash array. */ public PdfArray getDashArray() { return dashArray; } /** * Setter for the dash array. See {@link #getDashArray()} * @param dashArray New dash array. */ public void setDashArray(PdfArray dashArray) { this.dashArray = dashArray; } /** * Getter for the dash phase. * * The dash phase shall specify the distance into the dash pattern at which * to start the dash. The elements are expressed in user space units. * * @return The dash phase. */ public float getDashPhase() { return dashPhase; } /** * Setter for the dash phase. See {@link #getDashArray()} * @param dashPhase New dash phase. */ public void setDashPhase(float dashPhase) { this.dashPhase = dashPhase; } /** * Calculates and returns the next element which is either gap or dash. * @return The next dash array's element. */ public DashArrayElem next() { DashArrayElem ret = currentElem; if (dashArray.size() > 0) { currentIndex = (currentIndex + 1) % dashArray.size(); currentElem = new DashArrayElem(dashArray.getAsNumber(currentIndex).floatValue(), isEven(++elemOrdinalNumber)); } return ret; } /** * Resets the dash array so that the {@link #next()} method will start * from the beginning of the dash array. */ public void reset() { currentIndex = 0; elemOrdinalNumber = 1; initFirst(dashPhase); } /** * Checks whether the dashed pattern is solid or not. It's solid when the * size of a dash array is even and sum of all the units off in the array * is 0.<br/> * For example: [3 0 4 0 5 0 6 0] (sum is 0), [3 0 4 0 5 1] (sum is 1). */ public boolean isSolid() { if (dashArray.size() % 2 != 0) { return false; } float unitsOffSum = 0; for (int i = 1; i < dashArray.size(); i += 2) { unitsOffSum += dashArray.getAsNumber(i).floatValue(); } return Float.compare(unitsOffSum, 0) == 0; } private void initFirst(float phase) { if (dashArray.size() > 0) { while (phase > 0) { phase -= dashArray.getAsNumber(currentIndex).floatValue(); currentIndex = (currentIndex + 1) % dashArray.size(); elemOrdinalNumber++; } if (phase < 0) { --elemOrdinalNumber; --currentIndex; currentElem = new DashArrayElem(-phase, isEven(elemOrdinalNumber)); } else { currentElem = new DashArrayElem(dashArray.getAsNumber(currentIndex).floatValue(), isEven(elemOrdinalNumber)); } } } private boolean isEven(int num) { return (num % 2) == 0; } public class DashArrayElem { private float val; private boolean isGap; public DashArrayElem(float val, boolean isGap) { this.val = val; this.isGap = isGap; } public float getVal() { return val; } public void setVal(float val) { this.val = val; } public boolean isGap() { return isGap; } public void setGap(boolean isGap) { this.isGap = isGap; } } }