On 10/3/2015 5:40 AM, Stuart Marks wrote:
On 9/28/15 2:03 AM, Alexander Scherbatiy wrote:
Is it possible to use autoboxing in the fix instead of
Boolean.valueOf(someBooleanVariable)?
Hi,
These cases are all interesting because they end up requiring boxed
Boolean values, whether explicitly or implicitly via autoboxing:
1. AquaTabbedPaneUI.java -- use of boxed Boolean as a tri-state (!)
2. CAccessibility.java -- return value from Callable<Boolean>
3. LWCToolkit.java -- value in Properties (like Map<Object,Object>)
For #2 and #3 I think auto-boxing instead of valueOf() is just fine. I
guess using Boolean.TRUE or Boolean.FALSE instead of true or false is
ok, as it's a micro-optimization to prevent autoboxing from generating
a call to Boolean.valueOf(true|false). I'm sure the JIT compiler will
inline such calls, so this speeds up interpreted code a tiny bit at
the expense of a little verbosity in the code.
The explicit calls to Boolean.valueOf(some boolean expression) I think
can simply be replaced with autoboxing in all cases.
The weird one is in AquaTabbedPaneUI.java, which has
protected Boolean isDefaultFocusReceiver = null;
I do not mean to change the isDefaultFocusReceivertype type to
boolean. It was just interesting are there pros and cons to use a short
version with autoboxing for assignment:
isDefaultFocusReceiver = defaultFocusReceiver != null &&
defaultFocusReceiver.equals(component);
instead of the long version:
isDefaultFocusReceiver = Boolean.valueOf(defaultFocusReceiver !=
null && defaultFocusReceiver.equals(component));
Thanks,
Alexandr.
Ugh! It would be nice to get rid of null as a marker for uninitialized
state, but that might require too much analysis to show that the
change would be correct. This is, I think, the only case where the
code has to be explicit about dealing with a boxed Boolean object that
might be null, as opposed to true or false.
The only place that really has to do that is isDefaultFocusReceiver(),
which checks for null up front. I'm not sure that using
Boolean.valueOf() and Boolean.booleanValue() in the rest of the method
are really helpful in denoting that this is a boxed, nullable Boolean
though. So I'd switch to autoboxing here too.
s'marks
