What I don't understand is why you would want to use gcj and gij when a more robust java runtime and compiler is freely available at http://www-106.ibm.com/developerworks/views/linux/downloads.jsp ----- Original Message ----- From: "Joe Dumais" <jjejdumais@xxxxxxxxxxx> To: "For users of Fedora Core releases" <fedora-list@xxxxxxxxxx> Sent: Tuesday, March 16, 2004 6:56 PM Subject: Re: Using java in FC1(with eclipse)-help needed > gcj is the java compiler in the gnu suite. > gij is the java executable. What I have done is to link gij to a file > called > java. Then when I type in java somejavabytecode file, I am actually > executing gij, but it runs the same. For gcj, it is a little more complex > in that the equivalent for javac is "gcj -C" (capital C) which tells gcj to > compile to byte code. There are other options to gcj that allow compilation > to OS specific binary codes. You have a few options here, which is to > alias javac to "gcj -C" or to create an executable shell script file called > javac which calls "gcj -C". > > Michael Kearey wrote: > > > Mark Eggers wrote: > > > >> On Tue, 2004-03-16 at 12:21, fedora-list-request@xxxxxxxxxx wrote: > >> > >> > >> > >>> Kaustubh Ghosh wrote: > >> > >> > >> > >>> I am quite novice towards java programming in linux.To start with I > >>> installed j2re1.4.2_03 and also j2sdk1.4.2_04 in FC1(Both from > >>> java.sin.com).Now peculiar problems arise. > >>> When I type "java -version" it gives 1.3.1( > >>> When I type "/usr/java/j2sdk1.4.2_04/bin/java -version" it gives > >>> 1.4.2_04. > >>> Anyway I can compile any .java file with javac. > >>> But when I try to run it with java(any of the above) the gui would > >>> not come.(Hello World executes perfectly with System.out.println as > >>> also other non-gui programs). > >> > >> > >> > >> You have both Sun's Java and GNU's Java installed. GNU's Java comes by > >> default when you select all of the compilers during the install. > > > > > > GNU's Java RPMS for Fedora do not include any 'java' executable. This > > is what gcc-java package has for executables: > > > > /usr/bin/gcj > > /usr/bin/gcjh > > /usr/bin/jcf-dump > > /usr/bin/jv-scan > > > > And this is what libgcj has : > > > > /usr/bin/gij > > /usr/bin/grepjar > > /usr/bin/jar > > /usr/bin/jv-convert > > /usr/bin/rmic > > /usr/bin/rmiregistry > > > > gij is the bytecode interpretor for GNU java - the equivalent of > > 'java' executable BTW. > > > > > > I really don't know how you can be so convinced that the java -version > > that gives 1.3.1 is anything to do with GNU's java.. > > > >> > >> What I did was to find all the matching files in /usr that were supplied > >> by Sun's J2SDK and moved them to a /usr/<directory>/orig. I then added > >> my $JAVA_HOME/bin and $JAVA_HOME/jre/javaws to my PATH variable. javaws > >> is where Java WebStart is located. > >> > >> Like you, I have multiple Java versions installed. I usually keep the > >> current release and the previous release around in case something breaks > >> in the current release that didn't break in the previous release. > >> > >> To do this I make a symbolic link from where I installed Java to > >> /usr/java. > >> > >> For example, if I have j2sdk1.4.2_02 and j2sdk1.4.2_04 installed in > >> /usr, I will link /usr/j2sdk1.4.2_04 to /usr/java. > >> > >> I then set JAVA_HOME to /usr/java. > >> > >> This arrangement seems to work reasonably well. Another approach would > >> be to not make the link to /usr/java and just set the JAVA_HOME > >> environment variable appropriately. > >> > >> However, in both cases you'll need to take the GNU commands out of your > >> path and make sure that you have the Sun-supplied versions in your path. > > > > > > I'd do 'which java' to see the java executable that is found in path. > > Also do 'rpm -qa |grep j2' to see what, if any, RPMS are installed > > related to java 2... > > > > Yes, and sort out the PATH to have the correct java executable needed.. > > > > Cheers, > > Michael > > > > > > > > -- > fedora-list mailing list > fedora-list@xxxxxxxxxx > To unsubscribe: http://www.redhat.com/mailman/listinfo/fedora-list
