Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (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.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.pdfbox.pdmodel.graphics.form; import java.awt.geom.AffineTransform; import java.io.IOException; import java.io.InputStream; import org.apache.pdfbox.contentstream.PDContentStream; import org.apache.pdfbox.cos.COSArray; import org.apache.pdfbox.cos.COSDictionary; import org.apache.pdfbox.cos.COSFloat; import org.apache.pdfbox.cos.COSName; import org.apache.pdfbox.cos.COSStream; import org.apache.pdfbox.pdmodel.PDDocument; import org.apache.pdfbox.pdmodel.PDResources; import org.apache.pdfbox.pdmodel.ResourceCache; import org.apache.pdfbox.pdmodel.common.PDRectangle; import org.apache.pdfbox.pdmodel.common.PDStream; import org.apache.pdfbox.pdmodel.graphics.PDXObject; import org.apache.pdfbox.util.Matrix; /* TODO There are further Form XObjects to implement: + PDFormXObject |- PDReferenceXObject |- PDGroupXObject |- PDTransparencyXObject See PDF 32000 p111 When doing this all methods on PDFormXObject should probably be made final and all fields private. */ /** * A Form XObject. * * @author Ben Litchfield */ public class PDFormXObject extends PDXObject implements PDContentStream { private PDTransparencyGroupAttributes group; private final ResourceCache cache; /** * Creates a Form XObject for reading. * @param stream The XObject stream */ public PDFormXObject(PDStream stream) { super(stream, COSName.FORM); cache = null; } /** * Creates a Form XObject for reading. * @param stream The XObject stream */ public PDFormXObject(COSStream stream) { super(stream, COSName.FORM); cache = null; } /** * Creates a Form XObject for reading. * @param stream The XObject stream */ public PDFormXObject(COSStream stream, ResourceCache cache) { super(stream, COSName.FORM); this.cache = cache; } /** * Creates a Form Image XObject for writing, in the given document. * @param document The current document */ public PDFormXObject(PDDocument document) { super(document, COSName.FORM); cache = null; } /** * This will get the form type, currently 1 is the only form type. * @return The form type. */ public int getFormType() { return getCOSObject().getInt(COSName.FORMTYPE, 1); } /** * Set the form type. * @param formType The new form type. */ public void setFormType(int formType) { getCOSObject().setInt(COSName.FORMTYPE, formType); } /** * Returns the group attributes dictionary. * * @return the group attributes dictionary */ public PDTransparencyGroupAttributes getGroup() { if (group == null) { COSDictionary dic = (COSDictionary) getCOSObject().getDictionaryObject(COSName.GROUP); if (dic != null) { group = new PDTransparencyGroupAttributes(dic); } } return group; } public PDStream getContentStream() { return new PDStream(getCOSObject()); } @Override public InputStream getContents() throws IOException { return getCOSObject().createInputStream(); } /** * This will get the resources for this Form XObject. * This will return null if no resources are available. * * @return The resources for this Form XObject. */ @Override public PDResources getResources() { COSDictionary resources = getCOSObject().getCOSDictionary(COSName.RESOURCES); if (resources != null) { return new PDResources(resources, cache); } if (getCOSObject().containsKey(COSName.RESOURCES)) { // PDFBOX-4372 if the resource key exists but has nothing, return empty resources, // to avoid a self-reference (xobject form Fm0 contains "/Fm0 Do") // See also the mention of PDFBOX-1359 in PDFStreamEngine return new PDResources(); } return null; } /** * This will set the resources for this page. * @param resources The new resources for this page. */ public void setResources(PDResources resources) { getCOSObject().setItem(COSName.RESOURCES, resources); } /** * An array of four numbers in the form coordinate system (see below), * giving the coordinates of the left, bottom, right, and top edges, respectively, * of the form XObject's bounding box. * These boundaries are used to clip the form XObject and to determine its size for caching. * @return The BBox of the form. */ @Override public PDRectangle getBBox() { PDRectangle retval = null; COSArray array = (COSArray) getCOSObject().getDictionaryObject(COSName.BBOX); if (array != null) { retval = new PDRectangle(array); } return retval; } /** * This will set the BBox (bounding box) for this form. * @param bbox The new BBox for this form. */ public void setBBox(PDRectangle bbox) { if (bbox == null) { getCOSObject().removeItem(COSName.BBOX); } else { getCOSObject().setItem(COSName.BBOX, bbox.getCOSArray()); } } /** * This will get the optional matrix of an XObjectForm. It maps the form space to user space. * @return the form matrix if available, or the identity matrix. */ @Override public Matrix getMatrix() { return Matrix.createMatrix(getCOSObject().getDictionaryObject(COSName.MATRIX)); } /** * Sets the optional Matrix entry for the form XObject. * @param transform the transformation matrix */ public void setMatrix(AffineTransform transform) { COSArray matrix = new COSArray(); double[] values = new double[6]; transform.getMatrix(values); for (double v : values) { matrix.add(new COSFloat((float) v)); } getCOSObject().setItem(COSName.MATRIX, matrix); } /** * This will get the key of this XObjectForm in the structural parent tree. Required if the form * XObject contains marked-content sequences that are structural content items. * * @return the integer key of the XObjectForm's entry in the structural parent tree or -1 if * there isn't any. */ public int getStructParents() { return getCOSObject().getInt(COSName.STRUCT_PARENTS); } /** * This will set the key for this XObjectForm in the structural parent tree. * @param structParent The new key for this XObjectForm. */ public void setStructParents(int structParent) { getCOSObject().setInt(COSName.STRUCT_PARENTS, structParent); } }