Java tutorial
/* * * This file is part of the iText (R) project. Copyright (c) 1998-2019 iText Group NV * Authors: Bruno Lowagie, Paulo Soares, 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 Public License for more details. * You should have received a copy of the GNU Affero General Public 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 Public License. * * In accordance with Section 7(b) of the GNU Affero General Public 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; import com.itextpdf.text.error_messages.MessageLocalization; import com.itextpdf.text.pdf.internal.PdfIsoKeys; import java.io.IOException; import java.io.OutputStream; import java.util.LinkedHashMap; import java.util.Map.Entry; import java.util.Set; /** * <CODE>PdfDictionary</CODE> is the Pdf dictionary object. * <P> * A dictionary is an associative table containing pairs of objects. * The first element of each pair is called the <I>key</I> and the second * element is called the <I>value</I>. * Unlike dictionaries in the PostScript language, a key must be a * <CODE>PdfName</CODE>. * A value can be any kind of <CODE>PdfObject</CODE>, including a dictionary. * A dictionary is generally used to collect and tie together the attributes * of a complex object, with each key-value pair specifying the name and value * of an attribute.<BR> * A dictionary is represented by two left angle brackets (<<), followed by a * sequence of key-value pairs, followed by two right angle brackets (>>).<BR> * This object is described in the 'Portable Document Format Reference Manual * version 1.7' section 3.2.6 (page 59-60). * <P> * * @see PdfObject * @see PdfName * @see BadPdfFormatException */ public class PdfDictionary extends PdfObject { // CONSTANTS /** This is a possible type of dictionary */ public static final PdfName FONT = PdfName.FONT; /** This is a possible type of dictionary */ public static final PdfName OUTLINES = PdfName.OUTLINES; /** This is a possible type of dictionary */ public static final PdfName PAGE = PdfName.PAGE; /** This is a possible type of dictionary */ public static final PdfName PAGES = PdfName.PAGES; /** This is a possible type of dictionary */ public static final PdfName CATALOG = PdfName.CATALOG; // CLASS VARIABLES /** This is the type of this dictionary */ private PdfName dictionaryType = null; /** This is the hashmap that contains all the values and keys of the dictionary */ protected LinkedHashMap<PdfName, PdfObject> hashMap; // CONSTRUCTORS /** * Constructs an empty <CODE>PdfDictionary</CODE>-object. */ public PdfDictionary() { super(DICTIONARY); hashMap = new LinkedHashMap<PdfName, PdfObject>(); } public PdfDictionary(int capacity) { super(DICTIONARY); hashMap = new LinkedHashMap<PdfName, PdfObject>(capacity); } /** * Constructs a <CODE>PdfDictionary</CODE>-object of a certain type. * * @param type a <CODE>PdfName</CODE> */ public PdfDictionary(final PdfName type) { this(); dictionaryType = type; put(PdfName.TYPE, dictionaryType); } // METHODS OVERRIDING SOME PDFOBJECT METHODS /** * Writes the PDF representation of this <CODE>PdfDictionary</CODE> as an * array of <CODE>byte</CODE> to the given <CODE>OutputStream</CODE>. * * @param writer for backwards compatibility * @param os the <CODE>OutputStream</CODE> to write the bytes to. * @throws IOException */ @Override public void toPdf(final PdfWriter writer, final OutputStream os) throws IOException { PdfWriter.checkPdfIsoConformance(writer, PdfIsoKeys.PDFISOKEY_OBJECT, this); os.write('<'); os.write('<'); // loop over all the object-pairs in the HashMap PdfObject value; int type = 0; for (Entry<PdfName, PdfObject> e : hashMap.entrySet()) { e.getKey().toPdf(writer, os); value = e.getValue(); type = value.type(); if (type != PdfObject.ARRAY && type != PdfObject.DICTIONARY && type != PdfObject.NAME && type != PdfObject.STRING) os.write(' '); value.toPdf(writer, os); } os.write('>'); os.write('>'); } /** * Returns a string representation of this <CODE>PdfDictionary</CODE>. * * The string doesn't contain any of the content of this dictionary. * Rather the string "dictionary" is returned, possibly followed by the * type of this <CODE>PdfDictionary</CODE>, if set. * * @return the string representation of this <CODE>PdfDictionary</CODE> * @see com.itextpdf.text.pdf.PdfObject#toString() */ @Override public String toString() { if (get(PdfName.TYPE) == null) return "Dictionary"; return "Dictionary of type: " + get(PdfName.TYPE); } // DICTIONARY CONTENT METHODS /** * Associates the specified <CODE>PdfObject</CODE> as <VAR>value</VAR> with * the specified <CODE>PdfName</CODE> as <VAR>key</VAR> in this map. * * If the map previously contained a mapping for this <VAR>key</VAR>, the * old <VAR>value</VAR> is replaced. If the <VAR>value</VAR> is * <CODE>null</CODE> or <CODE>PdfNull</CODE> the key is deleted. * * @param key a <CODE>PdfName</CODE> * @param object the <CODE>PdfObject</CODE> to be associated with the * <VAR>key</VAR> */ public void put(final PdfName key, final PdfObject object) { if (key == null) throw new IllegalArgumentException(MessageLocalization.getComposedMessage("key.is.null")); if (object == null || object.isNull()) hashMap.remove(key); else hashMap.put(key, object); } /** * Associates the specified <CODE>PdfObject</CODE> as value to the * specified <CODE>PdfName</CODE> as key in this map. * * If the <VAR>value</VAR> is a <CODE>PdfNull</CODE>, it is treated just as * any other <CODE>PdfObject</CODE>. If the <VAR>value</VAR> is * <CODE>null</CODE> however nothing is done. * * @param key a <CODE>PdfName</CODE> * @param value the <CODE>PdfObject</CODE> to be associated to the * <VAR>key</VAR> */ public void putEx(final PdfName key, final PdfObject value) { if (key == null) throw new IllegalArgumentException(MessageLocalization.getComposedMessage("key.is.null")); if (value == null) return; put(key, value); } /** * Copies all of the mappings from the specified <CODE>PdfDictionary</CODE> * to this <CODE>PdfDictionary</CODE>. * * These mappings will replace any mappings previously contained in this * <CODE>PdfDictionary</CODE>. * * @param dic The <CODE>PdfDictionary</CODE> with the mappings to be * copied over */ public void putAll(final PdfDictionary dic) { hashMap.putAll(dic.hashMap); } /** * Removes a <CODE>PdfObject</CODE> and its <VAR>key</VAR> from the * <CODE>PdfDictionary</CODE>. * * @param key a <CODE>PdfName</CODE> */ public void remove(final PdfName key) { hashMap.remove(key); } /** * Removes all the <CODE>PdfObject</CODE>s and its <VAR>key</VAR>s from the * <CODE>PdfDictionary</CODE>. * @since 5.0.2 */ public void clear() { hashMap.clear(); } /** * Returns the <CODE>PdfObject</CODE> associated to the specified * <VAR>key</VAR>. * * @param key a <CODE>PdfName</CODE> * @return the </CODE>PdfObject</CODE> previously associated to the * <VAR>key</VAR> */ public PdfObject get(final PdfName key) { return hashMap.get(key); } /** * Returns the <CODE>PdfObject</CODE> associated to the specified * <VAR>key</VAR>, resolving a possible indirect reference to a direct * object. * * This method will never return a <CODE>PdfIndirectReference</CODE> * object. * * @param key A key for the <CODE>PdfObject</CODE> to be returned * @return A direct <CODE>PdfObject</CODE> or <CODE>null</CODE> */ public PdfObject getDirectObject(final PdfName key) { return PdfReader.getPdfObject(get(key)); } /** * Get all keys that are set. * * @return <CODE>true</CODE> if it is, otherwise <CODE>false</CODE>. */ public Set<PdfName> getKeys() { return hashMap.keySet(); } /** * Returns the number of <VAR>key</VAR>-<VAR>value</VAR> mappings in this * <CODE>PdfDictionary</CODE>. * * @return the number of <VAR>key</VAR>-<VAR>value</VAR> mappings in this * <CODE>PdfDictionary</CODE>. */ public int size() { return hashMap.size(); } /** * Returns <CODE>true</CODE> if this <CODE>PdfDictionary</CODE> contains a * mapping for the specified <VAR>key</VAR>. * * @return <CODE>true</CODE> if the key is set, otherwise <CODE>false</CODE>. */ public boolean contains(final PdfName key) { return hashMap.containsKey(key); } // DICTIONARY TYPE METHODS /** * Checks if a <CODE>Dictionary</CODE> is of the type FONT. * * @return <CODE>true</CODE> if it is, otherwise <CODE>false</CODE>. */ public boolean isFont() { return checkType(FONT); } /** * Checks if a <CODE>Dictionary</CODE> is of the type PAGE. * * @return <CODE>true</CODE> if it is, otherwise <CODE>false</CODE>. */ public boolean isPage() { return checkType(PAGE); } /** * Checks if a <CODE>Dictionary</CODE> is of the type PAGES. * * @return <CODE>true</CODE> if it is, otherwise <CODE>false</CODE>. */ public boolean isPages() { return checkType(PAGES); } /** * Checks if a <CODE>Dictionary</CODE> is of the type CATALOG. * * @return <CODE>true</CODE> if it is, otherwise <CODE>false</CODE>. */ public boolean isCatalog() { return checkType(CATALOG); } /** * Checks if a <CODE>Dictionary</CODE> is of the type OUTLINES. * * @return <CODE>true</CODE> if it is, otherwise <CODE>false</CODE>. */ public boolean isOutlineTree() { return checkType(OUTLINES); } /** * Checks the type of the dictionary. * @param type the type you're looking for * @return true if the type of the dictionary corresponds with the type you're looking for */ public boolean checkType(PdfName type) { if (type == null) return false; if (dictionaryType == null) dictionaryType = getAsName(PdfName.TYPE); return type.equals(dictionaryType); } // OTHER METHODS public void merge(final PdfDictionary other) { hashMap.putAll(other.hashMap); } public void mergeDifferent(final PdfDictionary other) { for (PdfName key : other.hashMap.keySet()) { if (!hashMap.containsKey(key)) hashMap.put(key, other.hashMap.get(key)); } } // DOWNCASTING GETTERS // @author Mark A Storer (2/17/06) /** * Returns a <CODE>PdfObject</CODE> as a <CODE>PdfDictionary</CODE>, * resolving indirect references. * * The object associated with the <CODE>PdfName</CODE> given is retrieved * and resolved to a direct object. * If it is a <CODE>PdfDictionary</CODE>, it is cast down and returned as * such. Otherwise <CODE>null</CODE> is returned. * * @param key A <CODE>PdfName</CODE> * @return the associated <CODE>PdfDictionary</CODE> object, * or <CODE>null</CODE> */ public PdfDictionary getAsDict(final PdfName key) { PdfDictionary dict = null; PdfObject orig = getDirectObject(key); if (orig != null && orig.isDictionary()) dict = (PdfDictionary) orig; return dict; } /** * Returns a <CODE>PdfObject</CODE> as a <CODE>PdfArray</CODE>, * resolving indirect references. * * The object associated with the <CODE>PdfName</CODE> given is retrieved * and resolved to a direct object. * If it is a <CODE>PdfArray</CODE>, it is cast down and returned as such. * Otherwise <CODE>null</CODE> is returned. * * @param key A <CODE>PdfName</CODE> * @return the associated <CODE>PdfArray</CODE> object, * or <CODE>null</CODE> */ public PdfArray getAsArray(final PdfName key) { PdfArray array = null; PdfObject orig = getDirectObject(key); if (orig != null && orig.isArray()) array = (PdfArray) orig; return array; } /** * Returns a <CODE>PdfObject</CODE> as a <CODE>PdfStream</CODE>, * resolving indirect references. * * The object associated with the <CODE>PdfName</CODE> given is retrieved * and resolved to a direct object. * If it is a <CODE>PdfStream</CODE>, it is cast down and returned as such. * Otherwise <CODE>null</CODE> is returned. * * @param key A <CODE>PdfName</CODE> * @return the associated <CODE>PdfStream</CODE> object, * or <CODE>null</CODE> */ public PdfStream getAsStream(final PdfName key) { PdfStream stream = null; PdfObject orig = getDirectObject(key); if (orig != null && orig.isStream()) stream = (PdfStream) orig; return stream; } /** * Returns a <CODE>PdfObject</CODE> as a <CODE>PdfString</CODE>, * resolving indirect references. * * The object associated with the <CODE>PdfName</CODE> given is retrieved * and resolved to a direct object. * If it is a <CODE>PdfString</CODE>, it is cast down and returned as such. * Otherwise <CODE>null</CODE> is returned. * * @param key A <CODE>PdfName</CODE> * @return the associated <CODE>PdfString</CODE> object, * or <CODE>null</CODE> */ public PdfString getAsString(final PdfName key) { PdfString string = null; PdfObject orig = getDirectObject(key); if (orig != null && orig.isString()) string = (PdfString) orig; return string; } /** * Returns a <CODE>PdfObject</CODE> as a <CODE>PdfNumber</CODE>, * resolving indirect references. * * The object associated with the <CODE>PdfName</CODE> given is retrieved * and resolved to a direct object. * If it is a <CODE>PdfNumber</CODE>, it is cast down and returned as such. * Otherwise <CODE>null</CODE> is returned. * * @param key A <CODE>PdfName</CODE> * @return the associated <CODE>PdfNumber</CODE> object, * or <CODE>null</CODE> */ public PdfNumber getAsNumber(final PdfName key) { PdfNumber number = null; PdfObject orig = getDirectObject(key); if (orig != null && orig.isNumber()) number = (PdfNumber) orig; return number; } /** * Returns a <CODE>PdfObject</CODE> as a <CODE>PdfName</CODE>, * resolving indirect references. * * The object associated with the <CODE>PdfName</CODE> given is retrieved * and resolved to a direct object. * If it is a <CODE>PdfName</CODE>, it is cast down and returned as such. * Otherwise <CODE>null</CODE> is returned. * * @param key A <CODE>PdfName</CODE> * @return the associated <CODE>PdfName</CODE> object, * or <CODE>null</CODE> */ public PdfName getAsName(final PdfName key) { PdfName name = null; PdfObject orig = getDirectObject(key); if (orig != null && orig.isName()) name = (PdfName) orig; return name; } /** * Returns a <CODE>PdfObject</CODE> as a <CODE>PdfBoolean</CODE>, * resolving indirect references. * * The object associated with the <CODE>PdfName</CODE> given is retrieved * and resolved to a direct object. * If it is a <CODE>PdfBoolean</CODE>, it is cast down and returned as such. * Otherwise <CODE>null</CODE> is returned. * * @param key A <CODE>PdfName</CODE> * @return the associated <CODE>PdfBoolean</CODE> object, * or <CODE>null</CODE> */ public PdfBoolean getAsBoolean(final PdfName key) { PdfBoolean bool = null; PdfObject orig = getDirectObject(key); if (orig != null && orig.isBoolean()) bool = (PdfBoolean) orig; return bool; } /** * Returns a <CODE>PdfObject</CODE> as a <CODE>PdfIndirectReference</CODE>. * * The object associated with the <CODE>PdfName</CODE> given is retrieved * If it is a <CODE>PdfIndirectReference</CODE>, it is cast down and returned * as such. Otherwise <CODE>null</CODE> is returned. * * @param key A <CODE>PdfName</CODE> * @return the associated <CODE>PdfIndirectReference</CODE> object, * or <CODE>null</CODE> */ public PdfIndirectReference getAsIndirectObject(final PdfName key) { PdfIndirectReference ref = null; PdfObject orig = get(key); // not getDirect this time. if (orig != null && orig.isIndirect()) ref = (PdfIndirectReference) orig; return ref; } }