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. */ /** * @author Erik M. Buck (Reviewed by Ankita Saxena */ package airviewer; import java.awt.geom.AffineTransform; import java.io.IOException; import static java.lang.Float.parseFloat; import static java.lang.Integer.parseInt; import java.rmi.server.UID; import java.util.ArrayList; import java.util.List; import java.util.logging.Level; import java.util.logging.Logger; import org.apache.pdfbox.pdmodel.PDDocument; import org.apache.pdfbox.pdmodel.PDPage; import org.apache.pdfbox.pdmodel.PDPageContentStream; import org.apache.pdfbox.pdmodel.common.PDRectangle; import org.apache.pdfbox.pdmodel.font.PDFont; import org.apache.pdfbox.pdmodel.font.PDType1Font; import org.apache.pdfbox.pdmodel.graphics.color.PDColor; import org.apache.pdfbox.pdmodel.graphics.color.PDDeviceRGB; import org.apache.pdfbox.pdmodel.interactive.annotation.PDAnnotation; import org.apache.pdfbox.pdmodel.interactive.annotation.PDAnnotationSquareCircle; import org.apache.pdfbox.pdmodel.interactive.annotation.PDAppearanceDictionary; import org.apache.pdfbox.pdmodel.interactive.annotation.PDAppearanceStream; import org.apache.pdfbox.pdmodel.interactive.annotation.PDBorderStyleDictionary; import org.apache.pdfbox.util.Matrix; /** * This is a helper class for creating the "Appearance Stream" for Text * annotations. This code is necessary because of bug PDFBox-2019. The PDF * Specification Section 8.4.1 lists the Appearance Streams as "Optional" in the * Appearance Dictionary for each annotation. "(Optional; PDF 1.2) An appearance * dictionary specifying how the annotation is presented visually on the page * (see Section 8.4.4, Appearance Streams and also implementation note 79 in * Appendix H). Individual annotation handlers may ignore this entry and provide * their own appearances." * * Even though "handlers may ignore this entry", PDFBox requires the presence of * the entry and will not display annotations that lack the entry. The * Appearance Stream(s) is a set of PDF drawing operators and operands that * specify how the annotation should appear when rendered. Acrobat and Preview * and some other programs supply a default appearance when the Appearance * Stream(s) is missing. PDFBox does not. * * @author Erik M. Buck (Reviewed by Ankita Saxena */ public class TextAnnotationMaker { /** * * @param document * @param arguments(pageNumber, lowerLeftX, lowerLeftY); String contents * @return */ public static List<PDAnnotation> make(PDDocument document, ArrayList<String> arguments) { assert null != arguments && arguments.size() == 4; assert null != document; List<PDAnnotation> result; try { int pageNumber = parseInt(arguments.get(0)); float lowerLeftX = parseFloat(arguments.get(1)); float lowerLeftY = parseFloat(arguments.get(2)); String contents = arguments.get(3); PDFont font = PDType1Font.HELVETICA_OBLIQUE; final float fontSize = 16.0f; // Or whatever font size you want. final float lineSpacing = 4.0f; float width = font.getStringWidth(contents) * fontSize / 1000.0f; // font.getStringWidth(contents) returns thousanths of PS point final float textHeight = fontSize + lineSpacing; try { PDPage page = document.getPage(pageNumber); PDColor red = new PDColor(new float[] { 1, 0, 0 }, PDDeviceRGB.INSTANCE); PDBorderStyleDictionary borderThick = new PDBorderStyleDictionary(); borderThick.setWidth(72 / 12); // 12th inch PDRectangle position = new PDRectangle(); position.setLowerLeftX(lowerLeftX); position.setLowerLeftY(lowerLeftY); position.setUpperRightX(lowerLeftX + width); position.setUpperRightY(lowerLeftY + textHeight); PDAnnotationSquareCircle aSquare = new PDAnnotationSquareCircle( PDAnnotationSquareCircle.SUB_TYPE_SQUARE); aSquare.setAnnotationName(new UID().toString()); aSquare.setContents(contents); PDColor fillColor = new PDColor(new float[] { .8f, .8f, .8f }, PDDeviceRGB.INSTANCE); aSquare.setInteriorColor(fillColor); aSquare.setRectangle(position); result = new ArrayList<>(page.getAnnotations()); // copy page.getAnnotations().add(aSquare); // The following lines are needed for PDFRenderer to render // annotations. Preview and Acrobat don't seem to need these. if (null == aSquare.getAppearance()) { aSquare.setAppearance(new PDAppearanceDictionary()); PDAppearanceStream annotationAppearanceStream = new PDAppearanceStream(document); position.setLowerLeftX(lowerLeftX - borderThick.getWidth() * 0.5f); position.setLowerLeftY(lowerLeftY - borderThick.getWidth() * 0.5f); position.setUpperRightX(lowerLeftX + width + borderThick.getWidth() * 0.5f); position.setUpperRightY(lowerLeftY + textHeight + borderThick.getWidth() * 0.5f); annotationAppearanceStream.setBBox(position); annotationAppearanceStream.setMatrix(new AffineTransform()); annotationAppearanceStream.setResources(page.getResources()); try (PDPageContentStream appearanceContent = new PDPageContentStream(document, annotationAppearanceStream)) { Matrix transform = new Matrix(); appearanceContent.transform(transform); appearanceContent.addRect(lowerLeftX, lowerLeftY, width, textHeight); appearanceContent.setNonStrokingColor(fillColor); appearanceContent.fill(); appearanceContent.beginText(); // Center text vertically, left justified appearanceContent.newLineAtOffset(lowerLeftX, lowerLeftY + textHeight * 0.5f - fontSize * 0.5f); appearanceContent.setFont(font, fontSize); appearanceContent.setNonStrokingColor(red); appearanceContent.showText(contents); appearanceContent.endText(); } aSquare.getAppearance().setNormalAppearance(annotationAppearanceStream); } //System.out.println(page.getAnnotations().toString()); } catch (IOException ex) { Logger.getLogger(DocumentCommandWrapper.class.getName()).log(Level.SEVERE, null, ex); result = null; } } catch (NumberFormatException | NullPointerException ex) { System.err.println("Non number encountered where floating point number expected."); result = null; } catch (IOException ex) { Logger.getLogger(TextAnnotationMaker.class.getName()).log(Level.SEVERE, null, ex); result = null; } return result; } }