Welcome to LQ.
Example, a 32bits RHEL 6 :
# rpm -Uvh jdk-1.6.0_37-fcs.i586.rpm
http://ftp.scientificlinux.org/linux...7-fcs.i586.rpm
Or # yum localinstall --nogpgcheck jdk-1.6.0_37-fcs.i586.rpm
# /usr/sbin/alternatives --install /usr/bin/java java /usr/java/jdk1.6.0_37/bin/java 2
# /usr/sbin/alternatives --config java
... And then select the "Sun Java".
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