Not able to find JAVA after installation

[Former Member]

Dear sir,

I would like to install ECC.6 on Red Hat Enterprises Linux 5.0 server for test purpose. I have already completed RHEL installation and perform all the recommendation written in SAP NOTES 171356, 1048303 etc.

I have installed JAVA as per the instructions given in the following links.

http://java.sun.com/j2se/1.4.2/install-linux.html

http://www.java.com/en/download/help/linux_install.xml

http://www.yolinux.com/TUTORIALS/LinuxTutorialJava.html#INSTALL_SDK

I am able to install JAVA on my Linux server but when I try to check whether the installation is successful or not I tried following commands, with the unexpected result.

#which java

/usr/bin/java

1. Java -fullversion*

gives details of by default installed java.

Can anybody help me or guide me to install java correctly on my Linux server?

Any other details if you like I will provide.

Regards

Ahsan

[Former Member]

This message was moderated.

[Former Member]

Hi

I have installed java on Linux by exactly performing your steps given, however when check the JAVA -Version it still says no java installed.

Detailed output.

-

---

[root@localhost /]# which java

/usr/bin/java

[root@localhost /]# java -version

java version "1.4.2"

gij (GNU libgcj) version 4.1.2 20070626 (Red Hat 4.1.2-14)

Copyright (C) 2006 Free Software Foundation, Inc.

This is free software; see the source for copying conditions. There is NO

warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

[root@localhost /]# ls -ltr

total 70406

-rw-rr 1 root root 35513469 May 10 2006 j2sdk-1_4_2_12-linux-i586.rpm

drwxr-xr-x 2 root root 4096 Oct 11 2006 srv

drwxr-xr-x 2 root root 4096 Oct 11 2006 opt

drwxr-xr-x 2 root root 4096 Oct 11 2006 mnt

drwxr-xr-x 2 root root 4096 Oct 11 2006 home

-rwxrwxrwx 1 root root 36337163 Sep 20 18:09 j2sdk-1_4_2_12-linux-i586.bin

drwx------ 2 root root 16384 Sep 24 22:18 lost+found

drwxr-xr-x 3 root root 4096 Sep 24 22:20 sapmnt

drwxr-xr-x 3 root root 4096 Sep 24 22:21 oracle

drwxr-xr-x 2 root root 4096 Sep 24 22:22 selinux

drwxr-xr-x 15 root root 4096 Sep 24 22:25 usr

drwxr-xr-x 4 root root 1024 Sep 24 22:26 boot

drwxr-xr-x 2 root root 4096 Sep 24 22:27 bin

drwxr-xr-x 14 root root 4096 Sep 24 22:27 lib

drwxr-xr-x 21 root root 4096 Sep 24 22:29 var

drwxr-xr-x 2 root root 12288 Sep 24 22:31 sbin

dr-xr-xr-x 141 root root 0 Sep 24 22:34 proc

drwxr-xr-x 11 root root 0 Sep 24 22:34 sys

drwxr-xr-x 2 root root 0 Sep 24 22:34 misc

drwxr-xr-x 2 root root 0 Sep 24 22:34 net

drwxr-xr-x 11 root root 4320 Sep 24 22:43 dev

drwxr-xr-x 3 root root 4096 Sep 24 22:45 media

drwxr-xr-x 4 root root 4096 Sep 24 22:46 dump

drwxr-xr-x 91 root root 4096 Sep 24 22:46 etc

drwxrwxr-x 9 root root 4096 Sep 24 22:57 j2sdk1.4.2_12

drwxrwxrwt 11 root root 4096 Sep 24 22:58 tmp

drwxr-x--- 15 root root 4096 Sep 24 22:58 root

[root@localhost /]# chmod 777 j2sdk-1_4_2_12-linux-i586.rpm

[root@localhost /]# rpm -Uvh j2sdk-1_4_2_12-linux-i586.rpm

Preparing... ########################################### [100%]

1:j2sdk ########################################### [100%]

[root@localhost /]# which java

/usr/bin/java

[root@localhost /]# java -fullversion

java full version "gcj-1.4.2"

[root@localhost /]# alternatives --config java

There is 1 program that provides 'java'.

Selection Command

-

---

*+ 1 /usr/lib/jvm/jre-1.4.2-gcj/bin/java

Enter to keep the current selection[+], or type selection number:

[root@localhost /]# ls -l /usr/bin/java

lrwxrwxrwx 1 root root 22 Sep 24 22:28 /usr/bin/java -> /etc/alternatives/java

[root@localhost /]# echo $JAVA_HOME

[root@localhost /]#

-

---

Regards

Ahsan

Edited by: Ahsan Rizvi on Sep 30, 2010 7:29 AM

[Former Member]

hi,

you forgot to set environment variable JAVA_HOME

set it to /usr/bin/java

[Former Member]

Dear Eric,

I have already set environment variable JAVA_HOME.

[root@localhost /]# export JAVA_HOME=/usr/java/j2re1.4.2_12/bin

[root@localhost /]# export PATH=$PATH:/usr/java/j2re1.4.2_12

However the result is below.

root@localhost /# which java

/usr/bin/java

root@localhost /# java -fullversion

java full version "gcj-1.4.2"

Please correct me if I'm not understanding anything.

Warm Regards

Ahsan

[Former Member]

Hi,

Please use the below mentioned commands

export JAVA_HOME=/usr/java/j2re1.4.2_12

export PATH=$PATH:/usr/java/j2re1.4.2_12/bin

Just a slight modification in your command.

Regards,

Deepak Kori

[hannes_kuehnemund]

Dear Ahsan,

the reason behind Deepak suggestion is, that the $PATH variable checks the path from the first given directory to the last given directory. If you place the /usr/java/j2re1.4.2_12 path at the end of the $PATH variable, if will still use a java that is found earlier in the path. Therefore, make sure that /usr/java/j2re1.4.2_12 comes first. With this you ensure that this directory is searched first.

Basically, $PATH variables are very basics in IT and work the same on Windows and UNIX systems. It is quite strange that you bypassed this concept until now

Thanks, Hannes