JfreeCHart 异常：Chart image not found

1. http://bbs.justep.com/thread-54775-1-1.html
2. java.lang.IllegalArgumentException: Width (0) and height (0) cannot be <= 0
3. at java.awt.image.DirectColorModel.createCompatibleWritableRaster(DirectColorModel.java:999)
4. at java.awt.image.BufferedImage.<init>(BufferedImage.java:323)
5. at org.jfree.chart.JFreeChart.createBufferedImage(JFreeChart.java:1394)
6. at org.jfree.chart.JFreeChart.createBufferedImage(JFreeChart.java:1376)
7. at org.jfree.chart.ChartUtilities.writeChartAsPNG(ChartUtilities.java:169)
8. at org.jfree.chart.ChartUtilities.saveChartAsPNG(ChartUtilities.java:305)
9. at org.jfree.chart.servlet.ServletUtilities.saveChartAsPNG(ServletUtilities.java:187)
10. at com.justep.chart.JustepChartHelper.executeChart(Unknown Source)
11. at com.justep.report.core.XReportChartHelper.executeChart(Unknown Source)
12. at com.justep.report.core.XReportHelper.a(Unknown Source)
13. at com.justep.report.core.XReportHelper.executeXReport(Unknown Source)
14. at com.justep.report.controller.ReportController.execute(Unknown Source)
15. at com.justep.report.controller.GenericControllerChain.execute(Unknown Source)
16. at com.justep.report.controller.DataController.execute(Unknown Source)
17. at com.justep.report.controller.GenericControllerChain.execute(Unknown Source)
18. at com.justep.report.controller.InitController.execute(Unknown Source)
19. at com.justep.report.controller.GenericControllerChain.execute(Unknown Source)
20. at com.justep.report.Servlet.a(Unknown Source)
21. at com.justep.report.Servlet.doPost(Unknown Source)
22. at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
23. at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
24. at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
25. at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
26. at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
27. at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
28. at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
29. at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
30. at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
31. at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
32. at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)
33. at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
34. at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
35. at java.lang.Thread.run(Thread.java:595)
36. 2013-9-3 11:53:35 org.apache.catalina.core.StandardWrapperValve invoke
37. 严重: Servlet.service() for servlet display-chart-servlet threw exception
38. javax.servlet.ServletException: Chart image not found
39. at org.jfree.chart.servlet.DisplayChart.service(DisplayChart.java:149)
40. at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
41. at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
42. at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
43. at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
44. at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
45. at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
46. at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
47. at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
48. at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
49. at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)
50. at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
51. at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
52. at java.lang.Thread.run(Thread.java:595)
53. java.lang.UnsupportedOperationException: Method failed: HTTP/1.1 500 Internal Server Error
54. at com.justep.res.proxy.ResourceProxy.a(Unknown Source)
55. at com.justep.res.proxy.ResourceProxy.doPost(Unknown Source)
56. at com.justep.res.proxy.ResourceProxy.doGet(Unknown Source)
57. at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
58. at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
59. at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
60. at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
61. at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
62. at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
63. at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
64. at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
65. at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
66. at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
67. at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)
68. at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
69. at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
70. at java.lang.Thread.run(Thread.java:595)

原因主要有以下几点:
1.chart组件的宽和高设置了100%.解决办法是设置成固定的宽和高.
2.chart组建的auto-load设置了true.改成false就好了.
3.当页面有两个报表以上时,刷新一个即可.