Applet加载错误-碧玉报告

Question

我的小程序遇到错误，无法解决。 我正在加载包含一个简单的jasper查看器的java applet。 加载小程序时，将引发以下异常：

SEVERE: Servlet.service() for servlet JasperReportServlet threw exception
java.lang.ClassNotFoundException: org.apache.commons.collections.ReferenceMap
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1358)
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1204)
    at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
    at net.sf.jasperreports.extensions.DefaultExtensionsRegistry.<init>(DefaultExtensionsRegistry.java:96)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
    at java.lang.Class.newInstance0(Class.java:355)
    at java.lang.Class.newInstance(Class.java:308)
    at net.sf.jasperreports.engine.util.ClassUtils.instantiateClass(ClassUtils.java:59)
    at net.sf.jasperreports.extensions.ExtensionsEnvironment.createDefaultRegistry(ExtensionsEnvironment.java:80)
    at net.sf.jasperreports.extensions.ExtensionsEnvironment.<clinit>(ExtensionsEnvironment.java:68)
    at net.sf.jasperreports.engine.util.JRStyledTextParser.<clinit>(JRStyledTextParser.java:76)
    at net.sf.jasperreports.engine.fill.JRBaseFiller.<init>(JRBaseFiller.java:182)
    at net.sf.jasperreports.engine.fill.JRVerticalFiller.<init>(JRVerticalFiller.java:77)
    at net.sf.jasperreports.engine.fill.JRVerticalFiller.<init>(JRVerticalFiller.java:87)
    at net.sf.jasperreports.engine.fill.JRVerticalFiller.<init>(JRVerticalFiller.java:57)
    at net.sf.jasperreports.engine.fill.JRFiller.createFiller(JRFiller.java:142)
    at net.sf.jasperreports.engine.fill.JRFiller.fillReport(JRFiller.java:78)
    at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:624)
    at com.dbhl.app.report.generator.JobUpdateGenerator.getJasperPrintObject(JobUpdateGenerator.java:279)
    at com.dbhl.app.report.JasperReportServlet.processJobUpdate(JasperReportServlet.java:153)
    at com.dbhl.app.report.JasperReportServlet.getJasperPrintObjectByLedgerType(JasperReportServlet.java:79)
    at com.dbhl.app.report.JasperReportServlet.service(JasperReportServlet.java:50)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:263)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:584)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
    at java.lang.Thread.run(Thread.java:619)

以下是我的applet配置，我正在使用标准Java部署工具包加载applet。

<script type="text/javascript" src="<%=basePath%>js/deployJava.js">
</script>

<script>
  var user = '<%=request.getParameter("user")%>';

  var attributes = {
    code : 'applet.EmbeddedViewerApplet.class',
    archive : '<%=basePath%>resources/appletviewer.jar,<%=basePath%>resources/jasperreports-applet-4.0.0.jar,<%=basePath%>resources/jasperreports-4.0.0.jar,<%=basePath%>resources/commons-collections-3.2.1.jar,<%=basePath%>resources/commons-logging-1.0.4.jar,<%=basePath%>resources/commons-beanutils-1.8.0.jar,<%=basePath%>resources/commons-digester-1.7.jar,<%=basePath%>resources/commons-javaflow-20060411.jar,<%=basePath%>resources/org-netbeans-core.jar',
    width : "100%",
    height : 600
  };

  var parameters = {
    fontSize : 16,
    REPORT_URL : '<%=basePath%>servlet/JasperReportServlet?startDate=<%=request.getParameter("startDate")%>&endDate=<%=request.getParameter("endDate")%>&user=' + user + '&reportType=<%=request.getParameter("reportType")%>'
  };

  var version = '1.4';
  deployJava.runApplet(attributes, parameters, version);
</script>

我在applet中需要的所有jar都存在于我的webroot的资源文件夹中，它们是

• appletviewer.jar
• commons-beanutils-1.8.0.jar
• commons-collections-3.2.1.jar
• commons-digester-1.7.jar
• commons-javaflow-20060411.jar
• commons-logging-1.0.4.jar
• jasperreports-4.0.0.jar
• jasperreports-applet-4.0.0.jar
• org-netbeans-core.jar

今天所有罐子都已签名，因此有效期不会到期。 我已经仔细检查了所有内容，但始终显示上述错误。 在iReport中，我可以查看报告并将其编译为jasper对象，没有错误。

控制面板中的Java控制台

我检查了临时缓存，确认收集文件已成功下载，并且在上述控制台日志中，它显示了jar已成功下载到主机。 为什么会发生ClassNotFoundException ？

Answer 1

错误来自服务器端，我在跟踪控制台日志后才知道，在我的服务器类路径comons-collections中丢失了，我添加了它，并且一切运行正常。