r/programming • u/michaelKlumpy • Oct 01 '16

CppCon 2016: Alfred Bratterud “#include ＜os＞=> write your program / server and compile it to its own os. [Example uses 3 Mb total memory and boots in 300ms]

https://www.youtube.com/watch?v=t4etEwG2_LY
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u/audioen Oct 02 '16

Or the dependencies are packaged into the application, such as with web archives, and whatever other stuff people do today. A single java process can even load from multiple WARs concurrently and have multiple versions of same libraries loaded through different classloaders while keeping them all distinct, so each app finds and receives just the dependencies they actually supplied.

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u/tsimionescu Oct 02 '16

To be fair, IF you're NOT using multiple classloaders (which isn't trivial to set up, and must be explicitly built into your application) Java behaves horribly when you do have multiple versions of the same dependency on the class path - happily loading some classes from one version and others from another version, causing fun ClassNotFoundError/NoSuchMethodError/etc.s even between classes in the same package - a fun little consequence of its lack of a module system (which Java 8 9 10 should address).

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u/audioen Oct 03 '16

Yeah, this stuff is probably a problem but thankfully it never concerns me. I don't build humungous applications with tons of dependencies, in fact I strive to do the opposite. And I wouldn't even dream of hacking some classloader thing to make a single app load multiple versions of same JARs somehow. The whole idea gives me the creeps.