Java tutorial
/* * The MIT License * * Copyright (c) 2004-2009, Sun Microsystems, Inc. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package hudson.util; import org.jfree.chart.JFreeChart; import org.jfree.chart.ChartRenderingInfo; import org.jfree.chart.ChartUtilities; import org.kohsuke.stapler.StaplerRequest; import org.kohsuke.stapler.StaplerResponse; import javax.servlet.ServletOutputStream; import javax.imageio.ImageIO; import java.io.IOException; import java.util.Calendar; import java.awt.image.BufferedImage; import java.awt.*; /** * A JFreeChart-generated graph that's bound to UI. * * <p> * This object exposes two URLs: * <dl> * <dt>/png * <dd>PNG image of a graph * * <dt>/map * <dd>Clickable map * </dl> * * @author Kohsuke Kawaguchi * @since 1.320 */ public abstract class Graph { private final long timestamp; private final int defaultW; private final int defaultH; private volatile JFreeChart graph; /** * @param timestamp * Timestamp of this graph. Used for HTTP cache related headers. * If the graph doesn't have any timestamp to tie it to, pass -1. */ protected Graph(long timestamp, int defaultW, int defaultH) { this.timestamp = timestamp; this.defaultW = defaultW; this.defaultH = defaultH; } protected Graph(Calendar timestamp, int defaultW, int defaultH) { this(timestamp.getTimeInMillis(), defaultW, defaultH); } /** * Actually render a chart. */ protected abstract JFreeChart createGraph(); private BufferedImage render(StaplerRequest req, ChartRenderingInfo info) { String w = req.getParameter("width"); if (w == null) w = String.valueOf(defaultW); String h = req.getParameter("height"); if (h == null) h = String.valueOf(defaultH); if (graph == null) graph = createGraph(); return graph.createBufferedImage(Integer.parseInt(w), Integer.parseInt(h), info); } /** * Renders a graph. */ public void doPng(StaplerRequest req, StaplerResponse rsp) throws IOException { if (req.checkIfModified(timestamp, rsp)) return; try { BufferedImage image = render(req, null); rsp.setContentType("image/png"); ServletOutputStream os = rsp.getOutputStream(); ImageIO.write(image, "PNG", os); os.close(); } catch (Error e) { /* OpenJDK on ARM produces an error like this in case of headless error Caused by: java.lang.Error: Probable fatal error:No fonts found. at sun.font.FontManager.getDefaultPhysicalFont(FontManager.java:1088) at sun.font.FontManager.initialiseDeferredFont(FontManager.java:967) at sun.font.CompositeFont.doDeferredInitialisation(CompositeFont.java:254) at sun.font.CompositeFont.getSlotFont(CompositeFont.java:334) at sun.font.CompositeStrike.getStrikeForSlot(CompositeStrike.java:77) at sun.font.CompositeStrike.getFontMetrics(CompositeStrike.java:93) at sun.font.Font2D.getFontMetrics(Font2D.java:387) at java.awt.Font.defaultLineMetrics(Font.java:2082) at java.awt.Font.getLineMetrics(Font.java:2152) at org.jfree.chart.axis.NumberAxis.estimateMaximumTickLabelHeight(NumberAxis.java:974) at org.jfree.chart.axis.NumberAxis.selectVerticalAutoTickUnit(NumberAxis.java:1104) at org.jfree.chart.axis.NumberAxis.selectAutoTickUnit(NumberAxis.java:1048) at org.jfree.chart.axis.NumberAxis.refreshTicksVertical(NumberAxis.java:1249) at org.jfree.chart.axis.NumberAxis.refreshTicks(NumberAxis.java:1149) at org.jfree.chart.axis.ValueAxis.reserveSpace(ValueAxis.java:788) at org.jfree.chart.plot.CategoryPlot.calculateRangeAxisSpace(CategoryPlot.java:2650) at org.jfree.chart.plot.CategoryPlot.calculateAxisSpace(CategoryPlot.java:2669) at org.jfree.chart.plot.CategoryPlot.draw(CategoryPlot.java:2716) at org.jfree.chart.JFreeChart.draw(JFreeChart.java:1222) at org.jfree.chart.JFreeChart.createBufferedImage(JFreeChart.java:1396) at org.jfree.chart.JFreeChart.createBufferedImage(JFreeChart.java:1376) at org.jfree.chart.JFreeChart.createBufferedImage(JFreeChart.java:1361) at hudson.util.ChartUtil.generateGraph(ChartUtil.java:116) at hudson.util.ChartUtil.generateGraph(ChartUtil.java:99) at hudson.tasks.test.AbstractTestResultAction.doPng(AbstractTestResultAction.java:196) at hudson.tasks.test.TestResultProjectAction.doTrend(TestResultProjectAction.java:97) ... 37 more */ if (e.getMessage().contains("Probable fatal error:No fonts found")) { rsp.sendRedirect2(req.getContextPath() + "/images/headless.png"); return; } throw e; // otherwise let the caller deal with it } catch (HeadlessException e) { // not available. send out error message rsp.sendRedirect2(req.getContextPath() + "/images/headless.png"); } } /** * Renders a clickable map. */ public void doMap(StaplerRequest req, StaplerResponse rsp) throws IOException { if (req.checkIfModified(timestamp, rsp)) return; String w = req.getParameter("width"); if (w == null) w = String.valueOf(defaultW); String h = req.getParameter("height"); if (h == null) h = String.valueOf(defaultH); ChartRenderingInfo info = new ChartRenderingInfo(); render(req, info); rsp.setContentType("text/plain;charset=UTF-8"); rsp.getWriter().println(ChartUtilities.getImageMap("map", info)); } }