Refactor to use FileTime API

[jorsol]

Closes #198

This still preserves backward compatibility with Java 7.

[michael-o]

What about tests? Are they implicitly tested?

[jorsol]

What about tests? Are they implicitly tested?

Ok, I thought that it was implicitly tested, but it looks that is not, I will add some tests for this and make sure that everything works correctly. Thanks for your input.

[jorsol]

This should be good to go, I added a test that checks the last modification time of every entry in the zip file in all available Time Zones (although probably with just a couple of them should be enough actually).

[olamy]

do we really need this noisy bot?

[hboutemy]

what about the @InlineMe suggestion: it seems a good idea to prepare about future removal, isn't it?

[jorsol]

what about the @InlineMe suggestion: it seems a good idea to prepare about future removal, isn't it?

That will require adding com.google.errorprone:error_prone_annotations:2.11.0 dependency, and the use of it it's just as a hint for IDEs, it's probably a good idea, but I don't like to add a dependency for no good reason, so if you like it I will add it.

[olamy]

what about the @InlineMe suggestion: it seems a good idea to prepare about future removal, isn't it?

That will require adding com.google.errorprone:error_prone_annotations:2.11.0 dependency, and the use of it it's just as a hint for IDEs, it's probably a good idea, but I don't like to add a dependency for no good reason, so if you like it I will add it.

personally I don't think this worth adding a new dependency

[hboutemy]

sure, not worth an additional dependency: thanks for evaluating