You may want to adjust the path and classpath settings after such an operation - but you wouldn't have to depending on how you use the JDK. I think that the best answer is, "Give it a try and find out how well it works." If you let us know what you learn, we all get to learn something. Good Luck.
It depends on whether or not the install affects the registry, installs files in other subdirectories, etc. I have not seen any documentation on it, but it seems that suddenly my javac is coming from 1.4 even though I have not changed my path and classpath.
I think would copy the .exe file and reinstall it with the install program. But if you decide to try installing with just copying the files in the subdir, let us know whether or not it works.
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