#2536 installation not working if only 64-bit java installed


windows installer of freecol-0.10.7 is complaining about missing java when only 64-bit java is installed

+ 64-bit windows 7
+ 64-bit java is installed (1.6.0_29 JDK & 1.7.0_01 JDK both including standalone JRE)
+ calling java/javaw from command line is succesful (known command)


  • Mike Pope
    Mike Pope

    • milestone: Fixed_0.10.7 --> Current
  • Evgeny

    Does using 64-bit JRE have any benefits against 32-bit? And why just do not install 32-bit JRE in addition? (For example - like explained here - http://www.java.com/en/download/faq/java_win64bit.xml )

    Should this case/question itself be considered a bug since it is so easy to fix?

  • SOA Guy
    SOA Guy

    Yes. 64-bit JRE can run natively on a 64-bit processor. Running 32-bit JRE on, say a Windows machine, will require the application to run through the 32-bit emulator, WOW64, http://en.wikipedia.org/wiki/WoW64. At the macro level, your call stack is Windows-64 (pick your particular version, XP, Vista, 7, 8) -> WOW64 -> JRE -> FreeCol. Running 64-bit Java, the call stack is shortened to Windows-64 -> JRE -> FreeCol. Removing a stack layer should have an obvious improvement on performance as well as the elimination of a possible layer of defects.

    Finally, if a person enjoys multiplying their security risk exposure, by all means, install as many different versions of Java as you like.

    In the end, it's been something like a year since I've installed an updated FreeCol. I can still run the old version under my 64-bit java (at least it starts - don't really play since it's old). The check for 32-bit Java fails during installation and I cannot install updates.

    Of course, the question exists, does WOW64 do a better job of translating 32-bit code (is there still 16-bit Java) than does the 64-bit JRE? That sounds like a great endeavor for a college student seeking a senior project.

  • Evgeny

    Thanks! I got the information! You are right. By theory, it really might be a performance drop of 5 to 15 percent.
    I just often use only 32-bit software (JRE) on 64-bit OS because in my perception it is still more stable (except 64-bit OS itself).

    Last edit: Evgeny 2013-08-30
  • Mike Pope
    Mike Pope

    • labels: installer --> Installer, Windows