Java tutorial
/* * Copyright 2004 by Paulo Soares. * * The contents of this file are subject to the Mozilla Public License Version 1.1 * (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.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the License. * * The Original Code is 'iText, a free JAVA-PDF library'. * * The Initial Developer of the Original Code is Bruno Lowagie. Portions created by * the Initial Developer are Copyright (C) 1999, 2000, 2001, 2002 by Bruno Lowagie. * All Rights Reserved. * Co-Developer of the code is Paulo Soares. Portions created by the Co-Developer * are Copyright (C) 2000, 2001, 2002 by Paulo Soares. All Rights Reserved. * * Contributor(s): all the names of the contributors are added in the source code * where applicable. * * Alternatively, the contents of this file may be used under the terms of the * LGPL license (the "GNU LIBRARY GENERAL PUBLIC LICENSE"), in which case the * provisions of LGPL are applicable instead of those above. If you wish to * allow use of your version of this file only under the terms of the LGPL * License and not to allow others to use your version of this file under * the MPL, indicate your decision by deleting the provisions above and * replace them with the notice and other provisions required by the LGPL. * If you do not delete the provisions above, a recipient may use your version * of this file under either the MPL or the GNU LIBRARY GENERAL PUBLIC LICENSE. * * This library is free software; you can redistribute it and/or modify it * under the terms of the MPL as stated above or under the terms of the GNU * Library General Public License as published by the Free Software Foundation; * either version 2 of the License, or any later version. * * This library 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 Library general Public License for more * details. * * If you didn't download this code from the following link, you should check if * you aren't using an obsolete version: * http://www.lowagie.com/iText/ */ package com.lowagie.text.pdf; import java.util.ArrayList; /** * An optional content group is a dictionary representing a collection of graphics * that can be made visible or invisible dynamically by users of viewer applications. * In iText they are referenced as layers. * * @author Paulo Soares (psoares@consiste.pt) */ public class PdfLayer extends PdfDictionary implements PdfOCG { protected PdfIndirectReference ref; protected ArrayList children; protected PdfLayer parent; protected String title; /** * Holds value of property on. */ private boolean on = true; /** * Holds value of property onPanel. */ private boolean onPanel = true; PdfLayer(String title) { this.title = title; } /** * Creates a title layer. A title layer is not really a layer but a collection of layers * under the same title heading. * @param title the title text * @param writer the <CODE>PdfWriter</CODE> * @return the title layer */ public static PdfLayer createTitle(String title, PdfWriter writer) { if (title == null) throw new NullPointerException("Title cannot be null."); PdfLayer layer = new PdfLayer(title); writer.registerLayer(layer); return layer; } /** * Creates a new layer. * @param name the name of the layer * @param writer the writer */ public PdfLayer(String name, PdfWriter writer) { super(PdfName.OCG); setName(name); ref = writer.getPdfIndirectReference(); writer.registerLayer(this); } String getTitle() { return title; } /** * Adds a child layer. Nested layers can only have one parent. * @param child the child layer */ public void addChild(PdfLayer child) { if (child.parent != null) throw new IllegalArgumentException("The layer '" + ((PdfString) child.get(PdfName.NAME)).toUnicodeString() + "' already has a parent."); child.parent = this; if (children == null) children = new ArrayList(); children.add(child); } /** * Gets the parent layer. * @return the parent layer or <CODE>null</CODE> if the layer has no parent */ public PdfLayer getParent() { return parent; } /** * Gets the children layers. * @return the children layers or <CODE>null</CODE> if the layer has no children */ public ArrayList getChildren() { return children; } /** * Gets the <CODE>PdfIndirectReference</CODE> that represents this layer. * @return the <CODE>PdfIndirectReference</CODE> that represents this layer */ public PdfIndirectReference getRef() { return ref; } /** * Sets the <CODE>PdfIndirectReference</CODE> that represents this layer. * This can only be done from PdfStamperImp. * @param ref The reference to the OCG object * @since 2.1.2 */ void setRef(PdfIndirectReference ref) { this.ref = ref; } /** * Sets the name of this layer. * @param name the name of this layer */ public void setName(String name) { put(PdfName.NAME, new PdfString(name, PdfObject.TEXT_UNICODE)); } /** * Gets the dictionary representing the layer. It just returns <CODE>this</CODE>. * @return the dictionary representing the layer */ public PdfObject getPdfObject() { return this; } /** * Gets the initial visibility of the layer. * @return the initial visibility of the layer */ public boolean isOn() { return this.on; } /** * Sets the initial visibility of the layer. * @param on the initial visibility of the layer */ public void setOn(boolean on) { this.on = on; } private PdfDictionary getUsage() { PdfDictionary usage = (PdfDictionary) get(PdfName.USAGE); if (usage == null) { usage = new PdfDictionary(); put(PdfName.USAGE, usage); } return usage; } /** * Used by the creating application to store application-specific * data associated with this optional content group. * @param creator a text string specifying the application that created the group * @param subtype a string defining the type of content controlled by the group. Suggested * values include but are not limited to <B>Artwork</B>, for graphic-design or publishing * applications, and <B>Technical</B>, for technical designs such as building plans or * schematics */ public void setCreatorInfo(String creator, String subtype) { PdfDictionary usage = getUsage(); PdfDictionary dic = new PdfDictionary(); dic.put(PdfName.CREATOR, new PdfString(creator, PdfObject.TEXT_UNICODE)); dic.put(PdfName.SUBTYPE, new PdfName(subtype)); usage.put(PdfName.CREATORINFO, dic); } /** * Specifies the language of the content controlled by this * optional content group * @param lang a language string which specifies a language and possibly a locale * (for example, <B>es-MX</B> represents Mexican Spanish) * @param preferred used by viewer applications when there is a partial match but no exact * match between the system language and the language strings in all usage dictionaries */ public void setLanguage(String lang, boolean preferred) { PdfDictionary usage = getUsage(); PdfDictionary dic = new PdfDictionary(); dic.put(PdfName.LANG, new PdfString(lang, PdfObject.TEXT_UNICODE)); if (preferred) dic.put(PdfName.PREFERRED, PdfName.ON); usage.put(PdfName.LANGUAGE, dic); } /** * Specifies the recommended state for content in this * group when the document (or part of it) is saved by a viewer application to a format * that does not support optional content (for example, an earlier version of * PDF or a raster image format). * @param export the export state */ public void setExport(boolean export) { PdfDictionary usage = getUsage(); PdfDictionary dic = new PdfDictionary(); dic.put(PdfName.EXPORTSTATE, export ? PdfName.ON : PdfName.OFF); usage.put(PdfName.EXPORT, dic); } /** * Specifies a range of magnifications at which the content * in this optional content group is best viewed. * @param min the minimum recommended magnification factors at which the group * should be ON. A negative value will set the default to 0 * @param max the maximum recommended magnification factor at which the group * should be ON. A negative value will set the largest possible magnification supported by the * viewer application */ public void setZoom(float min, float max) { if (min <= 0 && max < 0) return; PdfDictionary usage = getUsage(); PdfDictionary dic = new PdfDictionary(); if (min > 0) dic.put(PdfName.MIN_LOWER_CASE, new PdfNumber(min)); if (max >= 0) dic.put(PdfName.MAX_LOWER_CASE, new PdfNumber(max)); usage.put(PdfName.ZOOM, dic); } /** * Specifies that the content in this group is intended for * use in printing * @param subtype a name specifying the kind of content controlled by the group; * for example, <B>Trapping</B>, <B>PrintersMarks</B> and <B>Watermark</B> * @param printstate indicates that the group should be * set to that state when the document is printed from a viewer application */ public void setPrint(String subtype, boolean printstate) { PdfDictionary usage = getUsage(); PdfDictionary dic = new PdfDictionary(); dic.put(PdfName.SUBTYPE, new PdfName(subtype)); dic.put(PdfName.PRINTSTATE, printstate ? PdfName.ON : PdfName.OFF); usage.put(PdfName.PRINT, dic); } /** * Indicates that the group should be set to that state when the * document is opened in a viewer application. * @param view the view state */ public void setView(boolean view) { PdfDictionary usage = getUsage(); PdfDictionary dic = new PdfDictionary(); dic.put(PdfName.VIEWSTATE, view ? PdfName.ON : PdfName.OFF); usage.put(PdfName.VIEW, dic); } /** * Gets the layer visibility in Acrobat's layer panel * @return the layer visibility in Acrobat's layer panel */ public boolean isOnPanel() { return this.onPanel; } /** * Sets the visibility of the layer in Acrobat's layer panel. If <CODE>false</CODE> * the layer cannot be directly manipulated by the user. Note that any children layers will * also be absent from the panel. * @param onPanel the visibility of the layer in Acrobat's layer panel */ public void setOnPanel(boolean onPanel) { this.onPanel = onPanel; } }