Java类加载器按什么顺序加载类？

Question

I have two libraries of different versions in classpath. Which version will classloader load? How could I change it?

Answer 1

If you have

lib-v1.jar:lib-v2.jar

then it's in order. lib-v1.jar will be loaded first (analogous to PATH ).

I'd likely avoid this in practise (beyond uses for testing etc.) It can get confusing if you reference a library class in lib-v2.jar that's not in lib-v1.jar (possible if API's are retired). That way you'd load the initial class from v2, and further common classes from v1, and these may not be compatible.

Answer 2

这取决于将这些库列表提供给JVM的顺序。

Answer 3

Classloader has no information about your jar version. Generally You should avoid this kind of situations. You should hold the most recent version in your classpath