I have successfully developed a WAR file with Eclipse Version: 2024-06
(4.32.0) which has JRE System Library Java SE-17 and tested using
Tomcat 9.0.91 as a local host on Windows 11.
I had started work on this around a year ago and do not recall setting
up CATALINA_HOME or JAVA_HOME, but assume I must have done this somehow.
I have now been trying so set up a test system on another laptop
(Windows 10) with Tomcat 9.0.106 so that I can pass it to someone else
for testing.
I dropped the same WAR file used on my successful test system on this
other laptop and got
07-Jul-2025 17:09:06.094 SEVERE [http-nio-8080-exec-7]
org.apache.catalina.core.StandardWrapperValve.invoke Allocate
exception for servlet [amcon.mps_methods.Login
*Java.lang.UnsupportedClassVersionError: amcon/mps_methods/Login has
been compiled by a more recent version of the Java Runtime (class
file version 61.0), this version of the Java Runtime only recognizes
class file versions up to 52.0 (unable to load class
[amcon.mps_methods.Login])*
*On the Windows 10 test system I checked the Java Version*
*Java -version java version "1.8.0_451" Java(TM) SE Runtime
Environment (build 1.8.0_451-b10)*
*Then I downloaded Java 17 SDK and set a Windows environment variable
JAVA_HOME C:\Program Files\Java\jdk-17*
*I also set **a Windows environment variable CATALINA_HOME appropriately.*
*Tomcat then refused to run the JSP used to launch the Login Servlet (at
least with the 1.8 JRE I was able to execute the login JSP, but not the
Login servlet)*
**
*HTTP Status 404 – Not Found*
*
------------------------------------------------------------------------
TypeStatus Report
MessageJSP file [/MPSv3/Login.jsp] not found
DescriptionThe origin server did not find a current representation
for the target resource or is not willing to disclose that one exists.
------------------------------------------------------------------------
Apache Tomcat/9.0.106
*
Please could someone advise how I can correct my configuration on
the *Windows 10 test system *
*Many thanks, Alan Masters*
**
**
