I see this error very common in the blogs and SO but I could not somehow resolve it..
Error:
exception
javax.servlet.ServletException: Error instantiating servlet class DemoServlet org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070) org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611) org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) java.lang.Thread.run(Thread.java:701) root cause java.lang.ClassNotFoundException: DemoServlet org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1720) org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1571) org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070) org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611) org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) java.lang.Thread.run(Thread.java:701) Project folder structure..
[m1980@web449 sampleproject]$ tree . . ├── pom.xml ├── src │ └── main │ ├── java │ │ └── com │ │ └── prem │ │ └── controller │ │ └── DemoServlet.java │ ├── resources │ └── webapp │ ├── index.jsp │ └── WEB-INF │ └── web.xml └── target ├── classes │ └── com │ └── prem │ └── controller │ └── DemoServlet.class ├── maven-archiver │ └── pom.properties └── sampleproject ├── index.jsp ├── META-INF └── WEB-INF ├── classes │ └── com │ └── prem │ └── controller │ └── DemoServlet.class └── web.xml 22 directories, 9 files Im able to start apache and it runs without any problem...when I try http://localhost/sampleproject it displays the index page(Hello World!)..but when I try /welcome I get the above error...
web.xml
<web-app> <display-name>Archetype Created Web Application</display-name> <servlet> <servlet-name>test</servlet-name> <servlet-class>DemoServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>test</servlet-name> <url-pattern>/welcome</url-pattern> </servlet-mapping> </web-app> 
