How exactly does URLClassLoader work? java

So I know how to use URLClassLoader, and I know what it does, what I want to know is how exactly does it do it.

Basically I'm asking: Is it a live stream? Or does it do a temporary download and reads the classes lo开发者_如何学编程cally?

So if you where continually calling a method from a class you are loading with the URLClassLoader and you lost internet randomly would your java snip-it fail?

Or is it a one time thing and downloads it and if you lost internet it would be ok because it already downloaded it at the beginning?

Any information would be awesome, thank you.

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No. The classloader loads and caches content from the URL and does not refetch.

All custom class loader implementations have to work through defineClass which takes a byte[]. No streaming is possible with this API -- you either have all the bytes for the class or you don't.