Struts Exceptions during development

javax.servlet.ServletException: Wrapper cannot find servlet class org.apache.struts.action.ActionServlet or a class it depends on
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
java.lang.Thread.run(Unknown Source)

root cause
java.lang.ClassNotFoundException: org.apache.struts.action.ActionServlet
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1360)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1206)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
java.lang.Thread.run(Unknown Source)

To avoid these type of exceptions/erros place all the struts related jar files in the lib folder of your web application.