{"id":43,"date":"2007-06-16T09:29:32","date_gmt":"2007-06-16T14:29:32","guid":{"rendered":"http:\/\/javatechniques.com\/blog\/2007\/06\/16\/headless-exception-work-around\/"},"modified":"2007-06-16T09:29:32","modified_gmt":"2007-06-16T14:29:32","slug":"headless-exception-work-around","status":"publish","type":"post","link":"http:\/\/javatechniques.com\/blog\/2007\/06\/16\/headless-exception-work-around\/","title":{"rendered":"Headless Exception Work-Around"},"content":{"rendered":"<p>On upgrading a piece of (1.4-dependent) server-side software from 1.4.2_01 to 1.4.2_14, I began seeing errors that looked like:<\/p>\n<pre>\r\njava.awt.HeadlessException\r\n        at sun.java2d.HeadlessGraphicsEnvironment.getDefaultScreenDevice\r\n            (HeadlessGraphicsEnvironment.java:66)\r\n        at javax.swing.RepaintManager.getVolatileOffscreenBuffer\r\n            (RepaintManager.java:537)\r\n        at javax.swing.JComponent.paintDoubleBuffered(JComponent.java:4727)\r\n        at javax.swing.JComponent.paint(JComponent.java:798)\r\n        at edu.vt.cs.collab.cork.impl.servlet.CORKServlet.encodeComponentAsJPEG\r\n            (CORKServlet.java:617)\r\n        at org.isenhour.fin.inc.CEFChartWebView.writeChartImage(CEFChartWebView.java:97)\r\n        at org.isenhour.fin.inc.CEFChartWebView.writeStaticContent(CEFChartWebView.java:84)\r\n        at edu.vt.cs.collab.bridge.DefaultWebViewServlet.doGet(DefaultWebViewServlet.java:95)\r\n        at edu.vt.cs.collab.cork.impl.servlet.CORKServlet.doGet(CORKServlet.java:293)\r\n        at javax.servlet.http.HttpServlet.service(HttpServlet.java:740)\r\n        ....\r\n\r\n\r\n<\/pre>\n<p>The offending code segment was:<\/p>\n<pre>\r\n            img = new BufferedImage(sz.width, sz.height,\r\n                BufferedImage.TYPE_INT_RGB);\r\n            g = img.createGraphics();\r\n            g.setColor(Color.white);\r\n            g.fillRect(0, 0, sz.width, sz.height);\r\n            comp.setBounds(0, 0, sz.width, sz.height);\r\n            comp.paint(g);\r\n\r\n\r\n<\/pre>\n<p>where <code>comp<\/code> was a fairly uncomplicated Swing component. This turned out to be <a href=\"http:\/\/bugs.sun.com\/bugdatabase\/view_bug.do?bug_id=6189824\">Sun bug 6189824<\/a>. The work-around noted in the bug report, adding a call to:<\/p>\n<pre>\r\n\r\n    javax.swing.RepaintManager.currentManager(null).setDoubleBufferingEnabled(false);\r\n\r\n\r\n<\/pre>\n<p>seems to have fixed the problem.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>On upgrading a piece of (1.4-dependent) server-side software from 1.4.2_01 to 1.4.2_14, I began seeing errors that looked like: java.awt.HeadlessException at sun.java2d.HeadlessGraphicsEnvironment.getDefaultScreenDevice (HeadlessGraphicsEnvironment.java:66) at javax.swing.RepaintManager.getVolatileOffscreenBuffer (RepaintManager.java:537) at javax.swing.JComponent.paintDoubleBuffered(JComponent.java:4727) at javax.swing.JComponent.paint(JComponent.java:798) at edu.vt.cs.collab.cork.impl.servlet.CORKServlet.encodeComponentAsJPEG (CORKServlet.java:617) at org.isenhour.fin.inc.CEFChartWebView.writeChartImage(CEFChartWebView.java:97) at org.isenhour.fin.inc.CEFChartWebView.writeStaticContent(CEFChartWebView.java:84) at edu.vt.cs.collab.bridge.DefaultWebViewServlet.doGet(DefaultWebViewServlet.java:95) at edu.vt.cs.collab.cork.impl.servlet.CORKServlet.doGet(CORKServlet.java:293) at javax.servlet.http.HttpServlet.service(HttpServlet.java:740) &#8230;. The offending code segment was: img = new BufferedImage(sz.width, sz.height, BufferedImage.TYPE_INT_RGB); &hellip; <\/p>\n<p class=\"link-more\"><a href=\"http:\/\/javatechniques.com\/blog\/2007\/06\/16\/headless-exception-work-around\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Headless Exception Work-Around&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[],"class_list":["post-43","post","type-post","status-publish","format-standard","hentry","category-bug-fixes","entry"],"_links":{"self":[{"href":"http:\/\/javatechniques.com\/blog\/wp-json\/wp\/v2\/posts\/43","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/javatechniques.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/javatechniques.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/javatechniques.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/javatechniques.com\/blog\/wp-json\/wp\/v2\/comments?post=43"}],"version-history":[{"count":0,"href":"http:\/\/javatechniques.com\/blog\/wp-json\/wp\/v2\/posts\/43\/revisions"}],"wp:attachment":[{"href":"http:\/\/javatechniques.com\/blog\/wp-json\/wp\/v2\/media?parent=43"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/javatechniques.com\/blog\/wp-json\/wp\/v2\/categories?post=43"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/javatechniques.com\/blog\/wp-json\/wp\/v2\/tags?post=43"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}