from the java site? please use search engines and search for this before giving up and just asking questions
to get to the downloads page. click 'Download JRE 5.0 Update 7'. accept the lisence agreement and click a file to download under 'Linux Platform - J2SE(TM) Runtime Environment 5.0 Update 7' heading.
instructions are here
. if you download the rpm file, look at the rpm installation instructions; bin file look at self-extracting installation file.
download whatever one you like, .bin or .rpm.bin file.