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On Windows we can not make it totally portable (if you want the nice gui system tray and Windows Services entry) but we can make use of multiple instances. As such, I call this semi portable.
Manually Setup JRE
The main advantage is here is there are no entries in your registry and no automatic updates of Java (which I find can cause problems).
I install the version of Java I want on a test machine such as a VM and then copy the uncompressed Java folder over to your server and rename it according to the Linux instructions. For this example, C:\opt\jre1.6.0_16. The main advantage is here is there are no entries in your registry and no automatic updates of Java (which I find can cause problems).apache\java.
For older of Java versions go to the Java Archives site.
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