improved the headless detection to cover OpenJDK on ARM.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@19918 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/util/ChartUtil.java

@@ -118,6 +118,42 @@ public class ChartUtil {
             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.doGraph(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");