Most of these are harmless, and are best fixed simply by removing the
redundant check or assignment. The one in FlowType.compareBlocks,
however, revealed a real problem. This code checks for nullness of
`a` *after* having called a method on `a`. Assuming that `a` can
indeed be `null` here, the check must come first to avoid a
`NullPointerException`.
In several places, I saw code of this form:
if (thing == null)
assert thing != null : ... ;
I honestly don't understand the purpose of that `if` statement. Why
not just have the `assert` statement there directly? I removed the
seemingly irrelevant `if` statements in these cases, but if this is
some intentional pattern, please explain it to me.
In a few places where nullness is statically known but non-obvious,
add assert statements to point out what's going on to help future
developers.
Upgrade future such warnings to errors to keep us moving in a cleaner
direction.
In general, my approach was to try to eliminate each unused parameter
using Eclipse's "Change Method Signature" refactoring. That did not
always succeed: a parameter may be unused in some base class method,
but then be used in subclass's override of that method. In cases
where refactoring to eliminate a parameter failed, I instead annotated
the parameter with '@SuppressWarnings("unused")' to silence the
warning.
Note: this group of changes creates a significant risk of
incompatibility for third-party WALA code. Some removed parameters
change externally-visible APIs. Furthermore, these changes do not
necessarily lead to Java compilation errors. For example, suppose
third-party code subclasses a WALA class or interface, overrides a
method, but does not annotate that method as @Override. Removing a
parameter means that the third-party method no longer overrides. This
can quietly change code behavior without compile-time errors or
warnings. This is exactly why one should use @Override wherever
possible, but we cannot guarantee that third-party WALA users have
done that.
Along the way, I also converted many "for (;;)" loops into modern
"for (:)" loops. I didn't systematically look for all opportunities
to do this, though. I merely made this change where I was already
converting raw Iterator uses into modern Iterator<...> uses.
Better use of generics also allowed many casts to become statically
redundant. I have removed all such redundant casts.
Only three raw-types warnings remain after this batch of fixes. All
three involve raw uses of CallGraphBuilder. I've tried to fix these
too, but it quickly snowballs into a cascade of changes that may or
may not eventually reach a statically-type-save fixed point. I may
give these last few problem areas another go in the future. For now,
though, the hundreds of other fixes seem worth keeping even if there
are a few stragglers.
This commit may change some public APIs, but only by making weaker
type signatures stronger by replacing raw types with generic types.
For example, we may change something like "Set" into "Set<String>",
but we're not adding new arguments, changing any
underlying (post-generics-erasure) types, etc.
If a method is private, there's no risk that a subclass elsewhere
might be overriding it and depending on dynamic dispatch to choose the
right implementation. So all of these private methods can safely be
declared static without risk of regression in either WALA code or
unseen third-party code.
1) Structural changes in the AstTranslator to allow retranslation and generation of custom IR. This is mostly moving state from the translator itself into the context.
2) Some refactoring to share some AST generation code across the Java and JavaScript front ends.
3) Switching to the latest Rhino, release 1.7R3; this is a pervasive change to the JavaScript Rhino translator, since it involves switching to the new AST interface in Rhino.
4) Common code to, as an option, translate Do-style loops by replicating the loop body. This allows the use of CAstNode.LOOP forms for such loops.
5) Some bug fixes to the mechanisms of the CAstRewriter to handle weird control flow cases.
6) An example of retranslation to specialize JavaScript methods based on how many arguments they receive at call sites.
git-svn-id: https://wala.svn.sourceforge.net/svnroot/wala/trunk@4425 f5eafffb-2e1d-0410-98e4-8ec43c5233c4
1) extend ContextSelector interface to allow it to specify parameters of interest
2) extend filtering mechanism at call sites to allow CPA-style filtering when requested by contexts
3) various related fixes and extensions:
a) removed redundant code to handle dispatch for JavaScript, so now it shares the core mechanism
b) tighten types for operators that take an array of args - now the array is T[] at the cost of a few array allocation methods
c) a bit more support for empty int sets
d) void function objects
e) bug fixes for lexical scoping support, and adaptation to work with core dispatch mechanism
f) example of CPA-style sensitivity to handle nastiness in a JavaScript for(.. in ...) loop
git-svn-id: https://wala.svn.sourceforge.net/svnroot/wala/trunk@4150 f5eafffb-2e1d-0410-98e4-8ec43c5233c4
Julian Dolby
Ben Liblit
Juergen Graf
Julian Dolby
Manu Sridharan
msridhar1
dolby-oss
rmfuhrer
sjfink