Java tutorial
/* * $Id: PRAcroForm.java 3735 2009-02-26 01:44:03Z xlv $ * * Copyright 2001, 2002 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. * * This class written by Mark Thompson, Copyright (C) 2002 by Mark Thompson. * * 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; import java.util.HashMap; import java.util.Iterator; /** * This class captures an AcroForm on input. Basically, it extends Dictionary * by indexing the fields of an AcroForm * @author Mark Thompson */ public class PRAcroForm extends PdfDictionary { /** * This class holds the information for a single field */ public static class FieldInformation { String name; PdfDictionary info; PRIndirectReference ref; FieldInformation(String name, PdfDictionary info, PRIndirectReference ref) { this.name = name; this.info = info; this.ref = ref; } public String getName() { return name; } public PdfDictionary getInfo() { return info; } public PRIndirectReference getRef() { return ref; } }; ArrayList fields; ArrayList stack; HashMap fieldByName; PdfReader reader; /** * Constructor * @param reader reader of the input file */ public PRAcroForm(PdfReader reader) { this.reader = reader; fields = new ArrayList(); fieldByName = new HashMap(); stack = new ArrayList(); } /** * Number of fields found * @return size */ public int size() { return fields.size(); } public ArrayList getFields() { return fields; } public FieldInformation getField(String name) { return (FieldInformation) fieldByName.get(name); } /** * Given the title (/T) of a reference, return the associated reference * @param name a string containing the path * @return a reference to the field, or null */ public PRIndirectReference getRefByName(String name) { FieldInformation fi = (FieldInformation) fieldByName.get(name); if (fi == null) return null; return fi.getRef(); } /** * Read, and comprehend the acroform * @param root the document root */ public void readAcroForm(PdfDictionary root) { if (root == null) return; hashMap = root.hashMap; pushAttrib(root); PdfArray fieldlist = (PdfArray) PdfReader.getPdfObjectRelease(root.get(PdfName.FIELDS)); iterateFields(fieldlist, null, null); } /** * After reading, we index all of the fields. Recursive. * @param fieldlist An array of fields * @param fieldDict the last field dictionary we encountered (recursively) * @param title the pathname of the field, up to this point or null */ protected void iterateFields(PdfArray fieldlist, PRIndirectReference fieldDict, String title) { for (Iterator it = fieldlist.listIterator(); it.hasNext();) { PRIndirectReference ref = (PRIndirectReference) it.next(); PdfDictionary dict = (PdfDictionary) PdfReader.getPdfObjectRelease(ref); // if we are not a field dictionary, pass our parent's values PRIndirectReference myFieldDict = fieldDict; String myTitle = title; PdfString tField = (PdfString) dict.get(PdfName.T); boolean isFieldDict = tField != null; if (isFieldDict) { myFieldDict = ref; if (title == null) myTitle = tField.toString(); else myTitle = title + '.' + tField.toString(); } PdfArray kids = (PdfArray) dict.get(PdfName.KIDS); if (kids != null) { pushAttrib(dict); iterateFields(kids, myFieldDict, myTitle); stack.remove(stack.size() - 1); // pop } else { // leaf node if (myFieldDict != null) { PdfDictionary mergedDict = (PdfDictionary) stack.get(stack.size() - 1); if (isFieldDict) mergedDict = mergeAttrib(mergedDict, dict); mergedDict.put(PdfName.T, new PdfString(myTitle)); FieldInformation fi = new FieldInformation(myTitle, mergedDict, myFieldDict); fields.add(fi); fieldByName.put(myTitle, fi); } } } } /** * merge field attributes from two dictionaries * @param parent one dictionary * @param child the other dictionary * @return a merged dictionary */ protected PdfDictionary mergeAttrib(PdfDictionary parent, PdfDictionary child) { PdfDictionary targ = new PdfDictionary(); if (parent != null) targ.putAll(parent); for (Iterator it = child.getKeys().iterator(); it.hasNext();) { PdfName key = (PdfName) it.next(); if (key.equals(PdfName.DR) || key.equals(PdfName.DA) || key.equals(PdfName.Q) || key.equals(PdfName.FF) || key.equals(PdfName.DV) || key.equals(PdfName.V) || key.equals(PdfName.FT) || key.equals(PdfName.F)) { targ.put(key, child.get(key)); } } return targ; } /** * stack a level of dictionary. Merge in a dictionary from this level */ protected void pushAttrib(PdfDictionary dict) { PdfDictionary dic = null; if (!stack.isEmpty()) { dic = (PdfDictionary) stack.get(stack.size() - 1); } dic = mergeAttrib(dic, dict); stack.add(dic); } }