JSP Document - JSP Version Error

JSP Tutorials - Herong's Tutorial Examples

∟JSP Document - JSP Version Error

This section provides tutorial example on how to verify what JSP versions are supported by Tomcat server using an invalid version number in a JSP Document.

If you want to know what JSP versions are supported by Apache Tomcat server, you can specify an invalid version number in the root element of a JSP Document. Tomcat will return an error and list all JSP version it supports.

Here is my version test example in JSP Document XML format:

<?xml version="1.0"?>
<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="?">
<!-- jsp_version_error.jspx
 - Copyright (c) 2006 HerongYang.com. All Rights Reserved.
-->
<jsp:directive.page contentType="text/html"/>
<html><body>
<jsp:scriptlet>out.println("JSP Version Error");</jsp:scriptlet>
</body></html>
</jsp:root>

Save the above document on the Tomcat server at: \local\tomcat\webapps\ROOT\jsp_version_error.jspx.

Then open this JSP Document with a Web browser with this URL: http://localhost:8080/jsp_version_error.jspx. The follow error shows up in the browser:

HTTP Status 500 – Internal Server Error
Type Exception Report

Message /jsp_version_error.jspx (line: [2], column: [64])
 Invalid version number: [?], must be "1.2", "2.0", "2.1", "2.2" or "2.3"

Description The server encountered an unexpected condition that prevented
it from fulfilling the request.

Exception
org.apache.jasper.JasperException:
 /jsp_version_error.jspx (line: [2], column: [64])
 Invalid version number: [?], must be "1.2", "2.0", "2.1", "2.2" or "2.3"
 org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:42)
 org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:292)
 org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:115)
 org.apache.jasper.compiler.Validator$ValidateVisitor.visit(Validator.java:531)
 org.apache.jasper.compiler.Node$JspRoot.accept(Node.java:554)
 org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2389)
 org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2441)
 org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2447)
 org.apache.jasper.compiler.Node$Root.accept(Node.java:470)
 org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2389)
 org.apache.jasper.compiler.Validator.validateExDirectives(Validator.java:1856)
 org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:224)
 org.apache.jasper.compiler.Compiler.compile(Compiler.java:385)
 org.apache.jasper.compiler.Compiler.compile(Compiler.java:362)
 org.apache.jasper.compiler.Compiler.compile(Compiler.java:346)
 org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:603)
 org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:383)
 org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:386)
 org.apache.jasper.servlet.JspServlet.service(JspServlet.java:330)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
 org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

Apache Tomcat/9.0.12