Code Review Request: 7164636: (prefs) Cleanup src/macosx/classes/java/util/prefs (original) (raw)

Kurchi Hazra kurchi.subhra.hazra at oracle.com
Mon May 14 20:00:11 UTC 2012

Thanks for the detailed explanation. I have removed the default initializations: http://cr.openjdk.java.net/~khazra/7164636/webrev.01/

On 5/14/2012 10:07 AM, Chris Hegarty wrote: > I always thought that removing these superfluous "default" values > would be a good clean up opportunity. >> Maybe one to be added to the warnings/StringBuilder potential cleanup > targets for external folks? >> -Chris. >> On 14/05/12 17:41, Brian Goetz wrote: >> From a concurrency perspective it is also preferable to NOT initialize >> variables to their default values, as doing so can cause some weird >> problems. For example: >>>> class A { >> public int x = 0; >>>> public void increment() { ++x; } >> public int get() { return x; } >> } >>>> // Thread X >> // Assume: Thread X never touches 'a' again >> A a = new A(); >>>> // Thread Y >> // Assume: No other thread than Y touches 'a' >> if (a != null) { >> a.increment(); >> System.out.println(a.get()); >> } >>>> With the explicit initialization, this code could print zero (because >> the set of writes to 'x' contains two writes, one by X to zero and one >> by Y to 1), whereas without the explicit initialization, it would always >> print one. >>>> Now, this is an example of "improper publication" of the A by Thread X, >> but this is the sort of improper publication (where an object was >> initialized by one thread and then "handed off" to another) that was >> widely thought to be safe a long time ago and was enshrined in many >> examples, particularly Swing examples. >>>> The sharing here is clearly wrong, but the approach of not unnecessarily >> initializing non-final fields eliminates a path to tickling the improper >> publication into actually producing the wrong result. >>>> On 5/14/2012 5:28 AM, Chris Hegarty wrote: >>> This change looks fine to me. >>>>>> Trivially, changedFiles and cachedFiles do not need to be set to >>> null (I >>> believe this will generate a little less bytecode), as this is the >>> default reference value. Since you are in clean-up mode ;-) >>>>>> -Chris. >>>>>> On 11/05/2012 22:46, Kurchi Hazra wrote: >>>> Hi, >>>>>>>> This change aims at removing some rawtype usages in >>>> src/macosx/classes/java/util/prefs that were brought >>>> into jdk8 with the macport. I have added @Override tags too where >>>> applicable. >>>>>>>> Bug: http://bugs.sun.com/bugdatabase/viewbug.do?bugid=7164636 >>>> Webrev: http://cr.openjdk.java.net/~khazra/7164636/webrev.00/ >>>>>>>>>>>> Thanks, >>>> Kurchi >>>>

-Kurchi

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