Hi, I am using the Velocity Engine for the first time and need some help on the following issue. Thanks in advance.
I have a web application which uses Spring framework. To send the template based emails through application, I have added following to my Spring context xml file: <bean id="javaMailSender" class="org.springframework.mail.javamail.JavaMailSenderImpl"> <property name="host" value="mail.abc.com <http://mail.akazaresearch.com>"/> </bean> <bean id="mailMessage" class="org.springframework.mail.SimpleMailMessage"> <property name="from" value="abc_ad...@abc.com<chin_ad...@akazaresearch.com> "/> <property name="subject" value="Test email"/> </bean> <bean id="velocityEngine" class="org.springframework.ui.velocity.VelocityEngineFactoryBean"> <property name="velocityProperties"> <props> <prop key="resource.loader">class</prop> <prop key="class.resource.loader.class"> org.apache.velocity.runtime.resource.loader.ClasspathResourceLoader </prop> </props> </property> </bean> <bean id="mailManager" class="com.akazaresearch.phenonet.server.main.email.MailManagerImpl"> <property name="javaMailSender" ref="javaMailSender"/> <property name="mailMessage" ref="mailMessage"/> <property name="velocityEngine" ref="velocityEngine"/> </bean> MailManagerImpl is a class I have written sendEmail code to. When I deploy the war file of for web application to Tomcat 6 and try to start the tomcat from command prompt, I get ConcurrentModificationException during the tomcat method call org.apache.catalina.loader.WebappClassLoader.clearReferences(). I have pasted the exception stack trace at the end. I know the exception is thrown when Velocity Engine is initialized because if I remove the "velocityEngine" property mapping from "mailManager" bean, tomcat do not throw any exception during the initalization. After searching on web, I found that the system property "org.apache.catalina.loader. WebappClassLoader.ENABLE_CLEAR_REFERENCES" for tomcat is set to true by default and which is why Tomcat attempts to null out any static or final fields from loaded classes when a web application is stopped as a work around for apparent garbage collection bugs and application coding errors. I read about disabling this property but it took me to another set of tomcat exceptions. So probably this is of no use. I tried to use the "resource.loader" value as file for Velocity Engine but I got the same ConcurrentModificationException. Could some one please let me know how can I overcome the problem. Regards, Pradnya Exception stack trace: SEVERE: Exception during cleanup after start failed java.util.ConcurrentModificationException at java.util.HashMap$HashIterator.nextEntry(HashMap.java:841) at java.util.HashMap$EntryIterator.next(HashMap.java:883) at java.util.HashMap$EntryIterator.next(HashMap.java:881) at java.util.HashMap.putAllForCreate(HashMap.java:481) at java.util.HashMap.clone(HashMap.java:713) at org.apache.catalina.loader.WebappClassLoader.clearReferences(WebappCl assLoader.java:1621) at org.apache.catalina.loader.WebappClassLoader.stop(WebappClassLoader.j ava:1524) at org.apache.catalina.loader.WebappLoader.stop(WebappLoader.java:707) at org.apache.catalina.core.StandardContext.stop(StandardContext.java:45 57) at org.apache.catalina.core.StandardContext.start(StandardContext.java:4 387) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase .java:791) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:77 1) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:525) at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:830) at org.apache.catalina.startup.HostConfig.deployWARs(HostConfig.java:719 ) at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:490 ) at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1149) at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java :311) at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(Lifecycl eSupport.java:117) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053) at org.apache.catalina.core.StandardHost.start(StandardHost.java:719) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045) at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443 ) at org.apache.catalina.core.StandardService.start(StandardService.java:5 16) at org.apache.catalina.core.StandardServer.start(StandardServer.java:710 )
