Java tutorial
/* (c) 2014 Open Source Geospatial Foundation - all rights reserved * (c) 2001 - 2013 OpenPlans * This code is licensed under the GPL 2.0 license, available at the root * application directory. */ package org.geoserver.wms.map; import java.awt.AlphaComposite; import java.awt.Color; import java.awt.Rectangle; import java.awt.RenderingHints; import java.io.IOException; import java.io.OutputStream; import java.util.HashMap; import java.util.logging.Level; import java.util.logging.Logger; import org.geoserver.platform.Operation; import org.geoserver.platform.ServiceException; import org.geoserver.wms.DefaultWebMapService; import org.geoserver.wms.WMS; import org.geoserver.wms.WMSMapContent; import org.geoserver.wms.decoration.MapDecorationLayout; import org.geoserver.wms.map.PDFMapOutputFormat.PDFMap; import org.geotools.renderer.lite.StreamingRenderer; import org.springframework.util.Assert; import com.lowagie.text.Document; import com.lowagie.text.DocumentException; import com.lowagie.text.FontFactory; import com.lowagie.text.pdf.DefaultFontMapper; import com.lowagie.text.pdf.PdfContentByte; import com.lowagie.text.pdf.PdfGraphics2D; import com.lowagie.text.pdf.PdfTemplate; import com.lowagie.text.pdf.PdfWriter; import com.vividsolutions.jts.geom.Envelope; /** * Handles a GetMap request that spects a map in PDF format. * * @author Pierre-Emmanuel Balageas, ALCER (http://www.alcer.com) * @author Simone Giannecchini - GeoSolutions * @author Gabriel Roldan * @version $Id$ */ public class PDFMapResponse extends AbstractMapResponse { /** A logger for this class. */ private static final Logger LOGGER = org.geotools.util.logging.Logging .getLogger("org.vfny.geoserver.responses.wms.map.pdf"); /** * A kilobyte */ private static final int KB = 1024; private WMS wms; public PDFMapResponse(WMS wms) { super(PDFMap.class, PDFMapOutputFormat.MIME_TYPE); this.wms = wms; } /** * Writes the PDF. * <p> * NOTE: the document seems to actually be created in memory, and being written down to * {@code output} once we call {@link Document#close()}. If there's no other way to do so, it'd * be better to actually split out the process into produceMap/write? * </p> * * @see org.geoserver.ows.Response#write(java.lang.Object, java.io.OutputStream, * org.geoserver.platform.Operation) */ @Override public void write(Object value, OutputStream output, Operation operation) throws IOException, ServiceException { Assert.isInstanceOf(PDFMap.class, value); WMSMapContent mapContent = ((PDFMap) value).getContext(); final int width = mapContent.getMapWidth(); final int height = mapContent.getMapHeight(); if (LOGGER.isLoggable(Level.FINE)) { LOGGER.fine("setting up " + width + "x" + height + " image"); } try { // step 1: creation of a document-object // width of document-object is width*72 inches // height of document-object is height*72 inches com.lowagie.text.Rectangle pageSize = new com.lowagie.text.Rectangle(width, height); Document document = new Document(pageSize); document.setMargins(0, 0, 0, 0); // step 2: creation of the writer PdfWriter writer = PdfWriter.getInstance(document, output); // step 3: we open the document document.open(); // step 4: we grab the ContentByte and do some stuff with it // we create a fontMapper and read all the fonts in the font // directory DefaultFontMapper mapper = new DefaultFontMapper(); FontFactory.registerDirectories(); // we create a template and a Graphics2D object that corresponds // with it PdfContentByte cb = writer.getDirectContent(); PdfTemplate tp = cb.createTemplate(width, height); PdfGraphics2D graphic = (PdfGraphics2D) tp.createGraphics(width, height, mapper); // we set graphics options if (!mapContent.isTransparent()) { graphic.setColor(mapContent.getBgColor()); graphic.fillRect(0, 0, width, height); } else { if (LOGGER.isLoggable(Level.FINE)) { LOGGER.fine("setting to transparent"); } int type = AlphaComposite.SRC; graphic.setComposite(AlphaComposite.getInstance(type)); Color c = new Color(mapContent.getBgColor().getRed(), mapContent.getBgColor().getGreen(), mapContent.getBgColor().getBlue(), 0); graphic.setBackground(mapContent.getBgColor()); graphic.setColor(c); graphic.fillRect(0, 0, width, height); type = AlphaComposite.SRC_OVER; graphic.setComposite(AlphaComposite.getInstance(type)); } Rectangle paintArea = new Rectangle(width, height); StreamingRenderer renderer = new StreamingRenderer(); renderer.setMapContent(mapContent); // TODO: expose the generalization distance as a param // ((StreamingRenderer) renderer).setGeneralizationDistance(0); RenderingHints hints = new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); renderer.setJava2DHints(hints); // we already do everything that the optimized data loading does... // if we set it to true then it does it all twice... java.util.Map rendererParams = new HashMap(); rendererParams.put("optimizedDataLoadingEnabled", new Boolean(true)); rendererParams.put("renderingBuffer", new Integer(mapContent.getBuffer())); // we need the renderer to draw everything on the batik provided graphics object rendererParams.put(StreamingRenderer.OPTIMIZE_FTS_RENDERING_KEY, Boolean.FALSE); // render everything in vector form if possible rendererParams.put(StreamingRenderer.VECTOR_RENDERING_KEY, Boolean.TRUE); if (DefaultWebMapService.isLineWidthOptimizationEnabled()) { rendererParams.put(StreamingRenderer.LINE_WIDTH_OPTIMIZATION_KEY, true); } rendererParams.put(StreamingRenderer.SCALE_COMPUTATION_METHOD_KEY, mapContent.getRendererScaleMethod()); renderer.setRendererHints(rendererParams); Envelope dataArea = mapContent.getRenderingArea(); // enforce no more than x rendering errors int maxErrors = wms.getMaxRenderingErrors(); MaxErrorEnforcer errorChecker = new MaxErrorEnforcer(renderer, maxErrors); // Add a render listener that ignores well known rendering exceptions and reports back // non // ignorable ones final RenderExceptionStrategy nonIgnorableExceptionListener; nonIgnorableExceptionListener = new RenderExceptionStrategy(renderer); renderer.addRenderListener(nonIgnorableExceptionListener); // enforce max memory usage int maxMemory = wms.getMaxRequestMemory() * KB; PDFMaxSizeEnforcer memoryChecker = new PDFMaxSizeEnforcer(renderer, graphic, maxMemory); // render the map renderer.paint(graphic, paintArea, mapContent.getRenderingArea(), mapContent.getRenderingTransform()); // render the watermark MapDecorationLayout.Block watermark = RenderedImageMapOutputFormat.getWatermark(wms.getServiceInfo()); if (watermark != null) { MapDecorationLayout layout = new MapDecorationLayout(); layout.paint(graphic, paintArea, mapContent); } // check if a non ignorable error occurred if (nonIgnorableExceptionListener.exceptionOccurred()) { Exception renderError = nonIgnorableExceptionListener.getException(); throw new ServiceException("Rendering process failed", renderError, "internalError"); } // check if too many errors occurred if (errorChecker.exceedsMaxErrors()) { throw new ServiceException("More than " + maxErrors + " rendering errors occurred, bailing out", errorChecker.getLastException(), "internalError"); } // check we did not use too much memory if (memoryChecker.exceedsMaxSize()) { long kbMax = maxMemory / KB; throw new ServiceException( "Rendering request used more memory than the maximum allowed:" + kbMax + "KB"); } graphic.dispose(); cb.addTemplate(tp, 0, 0); // step 5: we close the document document.close(); writer.flush(); writer.close(); } catch (DocumentException t) { throw new ServiceException("Error setting up the PDF", t, "internalError"); } } }