It recently happened to me that I was stuck at work on a Windows installation without access to admin privileges. While I could use a bunch of portable apps I could not find a portable JDK. To get a portable JDK without admin privileges in Windows you have to follow three simple steps.
Download the JDK from Oracle (e.g. JDK 8 8u111).
If you want to use the x86 version simply open the .exe file with 7-Zip. It contains a single file
tools.zip, which contains all the files we need.
For x64 the tools.zip can be found in
Extract the tools.zip to the desired JDK directory (e.g. “D:\JavaJDK\”).
Now we need to unpack a few files packed with pack200. We do that by executing this script in a console window inside the root of the JDK directory (e.g. “D:\JavaJDK\”):
for /R %f in (.\*.pack) do @"%cd%\bin\unpack200" -r -v -l "" "%f" "%~pf%~nf.jar"
Congrats you now have a working, portable JDK!