Troy, This is mainly because most Java apps are pure Java and don't use JNI. But if you use JNI inside your application, I don't think the API allows you to select the arch, thus you use the default one wich depends on something I don't know! I just know that if you have the 64-bit Java installed you cannot use 32-bit libs and vice versa. Michel --On mardi 4 novembre 2008 11:05 -0600 Troy Dawson <[log in to unmask]> wrote: > > That is a very good question Michel. If you have both jdk's installed, > and both java compat's installed, which java does it choose. > > Well, the answer is "both" > > They only have to point to one java, because there only is one java, > javac, etc... > > If you do a comparison of jdk-1.6 i586 versus x86_64, the majority of > files are the same file. There is some files that are only in the i586 > (the java plugin mostly) and there are some files that are only in x86_64 > (some 64 bit libraries), but all the main programs are the same. > java is /usr/java/jdk1.6.0_10/bin/java for 32 and 64 bit > javac is /usr/java/jdk1.6.0_10/bin/javac for 32 and 64 bit > and so forth. > > It seems to work. > > Let me know if there are cases where it doesn't work. > > Thanks > Troy > > Michel Jouvin wrote: >> Troy, >> >> AFAIK, the only difference between both versions is about JNI which >> allows to use non-Java libraries from a Java application. If you install >> the i586 version, you can use 32-bit libraries, if you install x86_64 >> version, you can use 64-bit libraries. I am not convinced you can >> install both in fact (how Java will choose the one to use)... but I may >> be wrong. >> >> Cheers, >> >> Michel >> >> --On lundi 3 novembre 2008 14:57 -0600 Troy Dawson <[log in to unmask]> >> wrote: >> >>> OK, it should be working now. >>> On SL4 there is only i586 java, even on x86_64. This is because that is >>> what we started with, and it makes things simpler. >>> On SL5, we have both i586 and x86_64. This gives people more choices. >>> I have tried installing the java-1.6.0-sun-compat x86_64 and i586 on the >>> same x86_64 machine. They installed without any problem, except some >>> odd font errors when installing the 32 bit version. >>> But, without the 32 bit compat rpm installed, my browser didn't see the >>> java plugin, even though the i586 jdk was installed. >>> Troy >>> >>> Dr Andrew C Aitchison wrote: >>>> On Wed, 22 Oct 2008, Troy Dawson wrote: >>>> >>>>> Discussion Topic: Java - when will we upgrade to Java 1.6? >>>>> Conclusion: Many scientific programs really need us to update to java >>>>> 1.6, the biggest name is dCache. >>>>> We will put the latest java 1.6 into testing and let people test it >>>>> for a month. If we don't have any show stoppers, we will push it out >>>>> on December 1, 2008 >>>> Executive Summary: >>>> yum --enablerepo=sl-testing install java-1.6.0-sun-compat >>>> Error: Missing Dependency: jdk = 2000:1.5.0_16-fcs is needed by package >>>> java-1.5.0-sun-compat >>>> >>>> --- >>>> Suplementary question: >>>> We had >>>> java-1.5.0-sun-compat-1.5.0.16-1jpp.noarch.rpm >>>> which has been replaced by >>>> java-1.6.0-sun-compat-1.6.0.10-1.sl5.jpp.i586.rpm >>>> java-1.6.0-sun-compat-1.6.0.10-1.sl5.jpp.x86_64.rpm >>>> >>>> How do I choose which to install on an x86_64 machine ? >>>> --- >>>> >>>> -- More info about tbhe main problem: >>>> >>>> java-1.6.0-sun-compat-1.6.0.10-1.sl5.jpp.x86_64.rpm >>>> "replaces" jdk-1.6.0_10-fcs.x86_64.rpm but jdk-1.50... >>>> is needed by java-1.5.0-sun-compat-1.5.0.16-1.1.sl5.jpp.noarch.rpm >>>> which isn't (and since it is a -compat package maybe shouldn't be) >>>> "obsoleted" by java-1.6.0-sun-compat-1.6.0.10-1.sl5.jpp.*.rpm >>>> >>>> yum --enablerepo=sl-testing install java-1.6.0-sun-compat >>>> Loading "tsflags" plugin >>>> Loading "fastestmirror" plugin >>>> Loading "skip-broken" plugin >>>> Loading "priorities" plugin >>>> Loading "protectbase" plugin >>>> Loading "kmdl" plugin >>>> Loading "allowdowngrade" plugin >>>> Loading "fedorakmod" plugin >>>> Loading "changelog" plugin >>>> Loading "downloadonly" plugin >>>> Loading "kernel-module" plugin >>>> Loading mirror speeds from cached hostfile >>>> * dpmms-sl5: >>>> * sl-security: ftp.scientificlinux.org >>>> * sl-base: ftp.scientificlinux.org >>>> * dpmms-sl52-all: >>>> * sl-testing: ftp.scientificlinux.org >>>> 3786 packages excluded due to repository priority protections >>>> 0 packages excluded due to repository protections >>>> Setting up Install Process >>>> Parsing package install arguments >>>> Resolving Dependencies >>>> --> Running transaction check >>>> ---> Package java-1.6.0-sun-compat.i586 0:1.6.0.10-1.sl5.jpp set to be >>>> updated --> Processing Dependency: jdk = 2000:1.6.0_10-fcs for package: >>>> java-1.6.0-sun-compat ---> Package java-1.6.0-sun-compat.x86_64 >>>> 0:1.6.0.10-1.sl5.jpp set to be updated --> Running transaction check >>>> --> Processing Dependency: jdk = 2000:1.5.0_16-fcs for package: >>>> java-1.5.0-sun-compat ---> Package jdk.x86_64 2000:1.6.0_10-fcs set to >>>> be updated >>>> ---> Package jdk.i586 2000:1.6.0_10-fcs set to be updated >>>> --> Processing Dependency: jdk = 2000:1.5.0_16-fcs for package: >>>> java-1.5.0-sun-compat --> Finished Dependency Resolution >>>> Beginning Kernel Module Plugin >>>> Finished Kernel Module Plugin >>>> Error: Missing Dependency: jdk = 2000:1.5.0_16-fcs is needed by package >>>> java-1.5.0-sun-compat >>>> >>>> >>>> [ I'm adding these packages to my repo rather than using testing >>>> directly building a >>>> > > -- > __________________________________________________ > Troy Dawson [log in to unmask] (630)840-6468 > Fermilab ComputingDivision/LCSI/CSI DSS Group > __________________________________________________ ************************************************************* * Michel Jouvin Email : [log in to unmask] * * LAL / CNRS Tel : +33 1 64468932 * * B.P. 34 Fax : +33 1 69079404 * * 91898 Orsay Cedex * * France * *************************************************************