8 Replies Latest reply: Feb 22, 2013 5:13 PM by jschellSomeoneStoleMyAlias RSS

    Is JVM working?

    769160
      An important Java app quit working on my computer. Is there a way to test whether the JVM is healthy?

      Thanks,
        • 1. Re: Is JVM working?
          EJP
          Try any of the JVM tools, even 'java -version', 'keytool -help', 'rmiregistry', ...
          • 2. Re: Is JVM working?
            769160
            Thank you. I went to the cmd prompt and typed java-version and received a "not recognized" response. I don't know how to use the tools you mentioned, so I have to ask that now.

            Thanks,

            Edited by: user12101224 on Feb 21, 2013 4:44 AM
            • 3. Re: Is JVM working?
              gimbal2
              Add a space.
              java -version
              Now you're trying to execute a command java-version, that does indeed not exist.
              • 4. Re: Is JVM working?
                769160
                That worked. I get:
                java version "1.6.0_23"
                Java(TM) SE Runtime Environment (build 1.6.0_23-b05)
                Java HotSpot(TM) Client VM (build 19.0-b09, mixed mode)

                Any clue in that as to why the Java-based server application does not run? (It used to, but very slowly - I did a defrag and everything sped up - except now the Java app does not run at all)

                Thanks,
                • 5. Re: Is JVM working?
                  gimbal2
                  When you don't post any information other than "it doesn't work", nobody can help you. You must be getting an error, post it - in a forum related to the particular product you're using.
                  • 6. Re: Is JVM working?
                    769160
                    It doesn't work
                    That's what's so frustrating. I would have given them up front if there were any.

                    As far as I can tell the Java server app just starts and exists with no error messages and no logging. When it runs there is very verbose logging, but nothiing now.

                    That's why I wondered if the JVM were working.

                    Perhaps the JVM logs somewhere I don't know about. I would at least want to see some acknowlegement that it tried to run the app. ???

                    Thanks,
                    • 7. Re: Is JVM working?
                      gimbal2
                      Its not the job of the JVM to log - it is the job of the application to do so. Its a server, so check the server's logs. If there are none, read its documentation to see how you can make it do verbose logging.

                      If all else fails, you're of course entitled to just entirely remove anything related to Java and then reinstall, just to be sure.
                      That's why I wondered if the JVM were working.
                      Run another application. If that works, the runtime is ok. An IDE like Eclipse or Netbeans is a good bet.
                      • 8. Re: Is JVM working?
                        jschellSomeoneStoleMyAlias
                        user12101224 wrote:
                        As far as I can tell the Java server app just starts and exists with no error messages and no logging. When it runs there is very verbose logging, but nothiing now.
                        How exactly do you run it?
                        What OS are you running on?