I downloaded the source code of the book "Apache Struts 2 Web Application Development" by Dave Newton from the https://www.packtpub.com/books/content/support.
Chapter 2 had compile error with Apache Maven 3.5.0. $ mvn -version Apache Maven 3.5.0 (ff8f5e7444045639af65f6095c62210b5713f426; 2017-04-03T15:39:06-04:00) Maven home: /home/alkao/maven/apache-maven-3.5.0 Java version: 1.8.0_144, vendor: Oracle Corporation Java home: /home/alkao/jdk/jdk1.8.0_144/jre Default locale: en_CA, platform encoding: UTF-8 OS name: "linux", version: "4.4.0-21-generic", arch: "i386", family: "unix" To fix it, I removed just the <scope> tag in pom.xml. Then run mvn: $ cd /home/alkao/Struts2/Apache_Struts_2_Web_Application_Development/ch02/sanity $ mvn clean package Running wildfly-10.1.0.Final: $ JBOSS_HOME/bin/standalone.sh $ jboss-cli.sh --connect --command="deploy /home/alkao/Struts2/Apache_Struts_2_Web_Application_Development/ch02/sanity/target/ch02-sanity-1.0.war --force" Running these 3 http links resulted in the same error in the web browser below. Please help. Thanks. http://localhost:8080/ch02-sanity-1.0/index.html http://localhost:8080/ch02-sanity-1.0/sanity.jsp http://localhost:8080/ch02-sanity-1.0/sanity.action Error processing request Context Path: /ch02-convention-1.0 Servlet Path: /index.html Path Info: null Query String: null Stack Trace java.lang.NullPointerException com.opensymphony.xwork2.util.FileManager$FileRevision.needsReloading(FileManager.java:209) com.opensymphony.xwork2.util.FileManager.fileNeedsReloading(FileManager.java:60) com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.needsReload(XmlConfigurationProvider.java:325) org.apache.struts2.config.StrutsXmlConfigurationProvider.needsReload(StrutsXmlConfigurationProvider.java:168) com.opensymphony.xwork2.config.ConfigurationManager.conditionalReload(ConfigurationManager.java:220) com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:61) org.apache.struts2.dispatcher.Dispatcher.getContainer(Dispatcher.java:774) org.apache.struts2.dispatcher.ng.InitOperations.initStaticContentLoader(InitOperations.java:77) org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.init(StrutsPrepareAndExecuteFilter.java:49) io.undertow.servlet.core.LifecyleInterceptorInvocation.proceed(LifecyleInterceptorInvocation.java:111) org.wildfly.extension.undertow.security.RunAsLifecycleInterceptor.init(RunAsLifecycleInterceptor.java:84) io.undertow.servlet.core.LifecyleInterceptorInvocation.proceed(LifecyleInterceptorInvocation.java:97) io.undertow.servlet.core.ManagedFilter.createFilter(ManagedFilter.java:80) io.undertow.servlet.core.ManagedFilter.getFilter(ManagedFilter.java:66) io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:61) io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) io.undertow.servlet.handlers.FilterHandler.handleRequest(FilterHandler.java:84) io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62) io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78) io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131) io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57) io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46) io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64) io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60) io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77) io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50) io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43) io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61) io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:292) io.undertow.servlet.handlers.ServletInitialHandler.access$100(ServletInitialHandler.java:81) io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:138) io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135) io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48) io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43) io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44) io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44) io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44) io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44) io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44) io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:272) io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81) io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:104) io.undertow.server.Connectors.executeRootHandler(Connectors.java:202) io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:805) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) java.lang.Thread.run(Thread.java:748)
