[#693] Fix resource leak warnings for org.eclipse.cdt.core.utils

[ruspl-afed]

• use try-with-resources for AutoCloseable

Fixes #693

[ruspl-afed]

@jld01 we have more hidden resource leak issues near Dwarf and related types when exposing them via ISymbolReader adapter: it is really not clear when to close them properly. Idea to override finalize is not good for Java, since the usage of this method was deprecated long ago. But these seem to be out of scope here, since most probably the proper fix will cause breaking API changes.

[jld01]

These changes look positive, @ruspl-afed, but I'm struggling to understand why the dispose() methods are necessary in the first place. For example, the Dwarf section maps should fall out of scope with each Dwarf instance. Do you have any insight into what is preventing the garbage collector from doing its job here?

[ruspl-afed]

Do you have any insight into what is preventing the garbage collector from doing its job here?

TBH I have no idea why people were struggling with essential things here. Now I even not sure why we need to have it AutoClosable. Perhaps, they had some streams inside to be closed.

[jonahgraham]

The history of why it needs to be autocloseable and not wait until gc runs is in #132

But the short answer is that all these classes hold onto real files so waiting until gc is too late.

[jld01]

Thanks for the explanation, @jonahgraham. 👍