Hi, I have been studying alternatives for making the Geoserver startup.bat to find the location of jre from Windows 7 machine automatically. Currently the startup.bat checks only if the JAVA_HOME environment variable is set and if it is not then the script stops and asks user to set it. I believe that a long time ago the idea has been that one Java version on a computer is enough and the latest one is the best and everybody could be made happy by launching all programs from %JAVA_HOME%\bin\java.exe.
Now I can see from my two year old computer that Java is extremely wide spread - I found totally 28 copies of java.exe from it! Amazingly many programs seem to install with its own copy of jre. No wonder that our admins do not set JAVA_HOME at all for our computers. After a short web review I believe this is status quo nowadays and startup.bat can't rely on finding the JAVA_HOME variable. Literature review ============== 1) There seems to be a modern alternative for JAVA_HOME which is using Windows registry with key HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java. http://stackoverflow.com/questions/3930383/jre-installation-directory-in-windows However, at least on our computers those keys are not set. Conclusion: Not reliable. 2) If Java is installed with installer then the Windows start menu has a few Java control tools. Especially the information that is shown by the javacpl.exe tool is stored into file: C:\Users\[user_name]\AppData\LocalLow\Sun\Java\Deployment. The file contains rows like deployment.javaws.jre.0.path=C\:\\Program Files (x86)\\Java\\jre7\\bin\\javaw.exe deployment.javaws.jre.0.product=1.7.0_51 3) Usually one copy of java.exe and javaw.exe can be found either from \Windows\System32 directory or in case of 32-bit jre on 64-bit Windows, from \Windows\SysWOW64. Those executables seem to start the highest and latest jre version of all versions which are listed by javacpl.exe. 4) Jre can also be installed simply by copying the program files to some directory. In this case jre can't be found by checking the registry or AppData\LocalLow\Sun\Java\Deployment file. Sometimes this jre path is added into PATH variable but fortunately not so often nowadays. Now how should we fix the startup.bat file? What about making it to use this logic: 1) If JAVA_HOME is set as system or user variable it is probably done for reason so use it. 2) Check if there is java.exe in \System32. That would start 64-bit jre on 64-bit computers and 32-bit jre on 32-bit computers. 3) If 2) fails and computer is 64-bit version, try to find 32-bit jre with the SysWOW64 system. 4) If all previous fail, prompt user to edit startup.bat file and set JAVA_HOME there. -Jukka Rahkonen- ------------------------------------------------------------------------------ Infragistics Professional Build stunning WinForms apps today! Reboot your WinForms applications with our WinForms controls. Build a bridge from your legacy apps to the future. http://pubads.g.doubleclick.net/gampad/clk?id=153845071&iu=/4140/ostg.clktrk _______________________________________________ Geoserver-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geoserver-devel
