I just downloaded the Java SDK/JDK versions 5 and 6, and I just need the development tools (and some libraries) contained in the installation packages, I don't need to perform an installation and that's why I was only looking for a zip package at first (for Windows there is only an exe installation file), I only need to extract the contents of the installation packages, I think this can be done from the command line but so far I haven't found how to do this (I already considered WinRar and 7-Zip, but I really want to find how to do it without using these tools)
Have you done this before and how?
You can do the installation once and then zip up the installed stuff placed under \Programs\Java.
This can be unzipped elsewhere later and used as a JDK in most IDE's without needing a full reinstall (but then Windows does not know about it)