Issue
I am trying to move from Tomcat 7 to Tomcat 8. I use maven as build tool. From Tomcat 8 Maven Plugin for Java 8 I see that it is possible to use tomcat7-maven-plugin with Tomcat8. However, the issue here is Jasper complaints of an invalid JSP version when it should not actually.
pom.xml
<dependency>
<groupId>javax.faces</groupId>
<artifactId>jsf-api</artifactId>
<version>2.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.servlet.jsp</groupId>
<artifactId>javax.servlet.jsp-api</artifactId>
<version>2.3.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.el</groupId>
<artifactId>javax.el-api</artifactId>
<version>3.0.0</version>
<scope>provided</scope>
</dependency>
...
...
<plugin>
<groupId>org.apache.tomcat.maven</groupId>
<artifactId>tomcat7-maven-plugin</artifactId>
<version>2.2</version>
</plugin>
The error I get is
Jan 22, 2016 2:54:55 AM org.apache.jasper.compiler.TldLocationsCache tldScanJar
INFO: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
Jan 22, 2016 2:54:55 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [jsp] in context with path [/push] threw exception [/index.jsp (line: 7, column: 66) Invalid version number: "2.3", must be "1.2", "2.0", "2.1" or "2.2"] with root cause
org.apache.jasper.JasperException: /index.jsp (line: 7, column: 66) Invalid version number: "2.3", must be "1.2", "2.0", "2.1" or "2.2"
at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:42)
at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:443)
at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:149)
at org.apache.jasper.compiler.Validator$ValidateVisitor.visit(Validator.java:526)
at org.apache.jasper.compiler.Node$JspRoot.accept(Node.java:564)
at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2375)
at org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2427)
at org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2433)
at org.apache.jasper.compiler.Node$Root.accept(Node.java:474)
at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2375)
at org.apache.jasper.compiler.Validator.validateExDirectives(Validator.java:1798)
at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:217)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:373)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:353)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:340)
at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:646)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:357)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Since Tomcat 8 uses Jasper 2 to implement JSF 2.3 and from the below code for Jasper 2:-
public void visit(Node.JspRoot n) throws JasperException {
JspUtil.checkAttributes(TagConstants.ROOT_ACTION, n, jspRootAttrs, err);
String version = n.getTextAttribute("version");
if (!version.equals("1.2") && !version.equals("2.0") &&
!version.equals("2.1") && !version.equals("2.2") &&
!version.equals("2.3")) {
err.jspError(n, MESSAGES.invalidJspVersionNumber(version));
}
visitBody(n);
}
I suspect that the version of Jasper may not be the right one getting referenced causing the error, but I do not have a way to assess that. Any leads are appreciated!
Solution
This is an issue with tomcat7-maven-plugin which has support for just Tomcat 7 at the moment. There are recommendations on adjusting the embedded tomcat version at http://tomcat.apache.org/maven-plugin-trunk/tomcat7-maven-plugin/adjust-embedded-tomcat-version.html. However, it causes issue as described at- https://issues.apache.org/jira/browse/MTOMCAT-234
At the time of writing this, it still stands unresolved. I am considering to shift my entire project to Gradle for good, given that gradle-tomcat-plugin supports Tomcat 8.
Answered By - Phalgun
