There are two such diagnostics: one for collection methods and one for
equals(). See
<https://www.eclipse.org/eclipse/news/4.7/jdt.php#unlikely-argument-types>
for more information about these two new diagnostics.
For each of these diagnostics, I've set the severity level to
"warning" in projects that have some instances of the suspicious code,
or to "error" in projects that have no instances of the suspicious
code.
These should mostly be things that we've already decided earlier that
we explicitly don't want to "fix" because they simply disagree with
the WALA project's coding style.
The additional diagnostics are ones that were previously being
ignored, but which we seem to have been ignoring by default rather
than as a conscious choice.
For diagnostics of which we currently have *zero* instances, treat
these as errors rather than merely warnings. The intent is to
permanently lock out future regressions of things we've completely
fixed. In the future, whenever we fix the last instance of a given
warning in a given Eclipse project, we should also promote that
diagnostic to an error to keep things clean into the future.
The "potentially" qualifier is here because these methods are visible
outside the WALA source tree. These methods may seem OK to be static
based on the code we have here, but we have no way of knowing whether
third-party code expected to be able to subclass and override. I'm
going to play it safe and assume that we want to allow that.
Note that we are still allowing Eclipse warnings about methods that
can *definitely* be declared static; a different configuration option
controls these. For private methods, final methods, and methods in
final classes, if the code seems static-safe based on what we have
here, then that's good enough: we don't need to worry about
third-party overrides.
Specifically, we're turning off Eclipse warnings about missing version
constraints on required bundles ("Require-Bundle"), exported
packages ("Export-Package"), and imported packages ("Import-Package").
We're not turning these off absolutely everywhere, though: only in
packages where one or more such warnings were actually being reported.
So if a given package was already providing all version constraints
for, say, package imports, then we've kept that warning on in that
package.
Honestly I don't entirely understand the practical implications of
these warnings. However, there were 355 of them across many WALA
subprojects. I take this as evidence that the WALA developers do not
consider these version constraints to be important. Therefore, we may
as well stop warning about something we have no intention of fixing.
That being said, if we *do* want to fix some or all of these, I
welcome any advice on what those fixes should look like. I am rather
ignorant about all things OSGi.
Manu requested that we use this approach instead of adding
`@SuppressWarnings("unused")` at each affected catch block. That
seems reasonable to me, given the large number of such warnings and
the lack of likely harm from ignoring such caught exceptions.
These changes turn off Eclipse warnings for Javadoc tags without
descriptions. In some subprojects, we turn these off entirely. In
others, leave on missing-descrption checks for "@return" tags only.
We don't turn this warning off in all projects. Rather, we turn it
off only in projects that were producing at least one such warning.
In other words, if a project was already completely "clean" with
respect to this warning, then we leave this warning enabled for that
project.
Turning off these warnings is a partial declaration of Javadoc
bankruptcy. In an ideal world, we would enable and fix all of these
warnings. However, there are 576 of them. Apparently the WALA team's
implicit coding style says that omitting descriptions is OK. If
there's no intent to systematically add descriptions, then we may as
well turn off these warnings so that we can see other warnings that we
may want to fix.
I think the "target/p2artifacts.xml" and "target/p2content.xml" files
are generated by Maven. They are well-formed XML but Eclipse's XML
validator legitimately warns that they lack grammar constraints.
Since we're not maintaining the tool that creates these files, we are
not in a position to do anything about that. Therefore, we may as
well exclude these from validation entirely. That way we can
more-clearly recognize warnings that we *can* do something about.
As created by Tycho Surefire, these files are XML documents without
DTD or XML Schema declarations. The XML validator warns about this
omission. However, Surefire is not a WALA component. We are not in a
suitable position to change it to include XML schema or DTD
declarations in the XML files it generates. Better, then, to ignore
this benign problem so we can focus on warnings that we can act on
directly.
Eclipse validation warns about invalid HTML content in all
Maven-generated "target/site/dependency-convergence.html" files. The
warnings are legitimate: these HTML files are indeed invalid.
However, we don't maintain the tool that generates these files, so we
are not in a position to fix them. Better, therefore, to suppress
these warnings so that we can notice and fix other problems over which
we do have control.
In general, the WALA code base is not really ready for nullness
checking. It would be nice if we got there some day, but I'm not
planning to take that on now or any time soon. Until then, it's not
useful to warn about missing @NonNullByDefault declarations on WALA
packages.
See also older commit 7b6811b.
Ben Liblit
Manu Sridharan
Julian Dolby
Manu Sridharan
dolby-oss