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Building the JDK on Debian GNU/Linux

Posted by ryuzaki0 on from the first-invent-the-pc dept.

Ivan Tarasov writes "Ever wanted to hack the JDK sources to get rid of some nasty bug which bothered you for so long, but was embarrassed by the complexity of the JDK build process? Now you have a good tutorial on how to do it on Debian GNU/Linux: last night I posted a blog entry on how to build the JDK 6 (sources of which are available at the Peabody site). This entry describes in detail which packages you need installed, how do you tweak the sources to make them buildable and how to proceed with the build. The build process for other Linux distributions must be very similar, so don't turn away if you don't use Debian. There is also a nice blog entry by Cay Horstmann "Honey, I built the JDK! (on Ubuntu)"."

3 of 27 comments (clear)

  1. Re:License? by ForumTroll · · Score: 2, Informative

    IIRC you can modify it as much as you like for your own personal use but you can't redistribute it.

    --
    "A Lisp programmer knows the value of everything, but the cost of nothing." - Alan Perlis
  2. Re:GCJ by kwark · · Score: 2, Informative

    Once I thought that using gcj might be fine for running cli java programs but I found that gcj had the following problems:
    -the ahead of time compiling requires ALL sources to be compiled even though they are not needed at runtime. eg commons-cli.jar depends on commons-lang.jar in gcj as opposed to use in the Sun JVM.
    -it is very slow in some areas (about 3 times slower during disk IO and md5 checksumming)
    -I couldn't get it to create static binaries (dev. on Debian/unstable to run on Debian/stable), but this could be my fault.

    The only good thing was the slightly faster launch times (about 0.2ms on a process that runs 1.2ms total) compared to the Sun JVM. But since the program is only launched about 5 times per hour why bother.

    This was with gcj-4.0 some months ago.

  3. Re:Not the real problem by BigFootApe · · Score: 3, Informative
    Are you thinking that Sun JDK will conflict with, say, SableVM? Milarky! You just use update-alternatives to point javac, java, javaw, etc. at Sun JDK as the primary provider of said facility.

    e.g.
    update-alternatives --config java
     
    There are 4 alternatives which provide `java'.
     
    Selection Alternative
      1 /usr/bin/gij-wrapper-4.0
    *2 /usr/lib/j2sdk1.5-sun/bin/java
    +3 /usr/lib/jvm/java-gcj/jre/bin/java
      4 /usr/bin/gij-wrapper-4.1
     
    Press enter to keep the default[*], or type selection number: 2
    Using `/usr/lib/j2sdk1.5-sun/bin/java' to provide `java'.
    Simple, no?

    Sorry, it would look nicer if slashdot accepted preformatted text :(