Preserve order in collections.

[carmenerre]

This MR tries to solve #146

It replaces the use of HashMap with LinkedHashMap, which preserves the performance improvement done in #144 but keeps the insertion order in collections.

Because LinkedHashMap is not synchronized, it has been wrapped using Collections.synchronizedMap method.

[goneall]

Thanks @carmenerre - great improvement to the code.

[beltran-rubo]

@goneall any ETA for a new release in June? This is a great improvement, thanks.

[goneall]

@beltran-rubo - would you want a complete release of all the java tools or just this library? I could spin the library version pretty quickly if it helps. Otherwise, it will probably be towards the end of June for a release of the complete set of Java tools as I'm working on a release of the online tools over the next week or two.

[beltran-rubo]

We are using the Java library itself, it would be great to get it sooner than later including this improvement. Thanks!

[goneall]

We are using the Java library itself, it would be great to get it sooner than later including this improvement. Thanks!

In that case I'll plan on producing a release of this library over the next couple of days.

[goneall]

@beltran-rubo - Totally different topic - as a user of the library directly, would you be interested, available to review the approach and design for the SPDX 3 changes? I'm just starting to implement and there are some breaking changes I'd like to get feedback on before going too far.

I just created #178 to track feedback prior to a pull request being created.

[beltran-rubo]

Thanks! Still a bit early to move to version 3 on our side but we can help with the revision and testing.

[goneall]

@beltran-rubo The release with this fix has been published: https://github.com/spdx/Spdx-Java-Library/releases/tag/v1.1.7
It should be available in Maven Central soon.