Hi Mike,
Some comments about the test...
40 String benchmark = "exemplar"; 41 String
constructorCopy = new String(benchmark); 42 String jlaCopy =
jla.newStringUnsafe(benchmark.toCharArray()); 43 44 if
(constructorCopy == constructorCopy) { 45 throw new
Error("should be different instances"); 46 }
Wouldn't this always throw error? You really wanted to test benchmark
== constructorCopy, right?
47 if (!benchmark.equals(constructorCopy)) { 48
throw new Error("Copy not equal"); 49 } 50 if (0 !=
Objects.compare(benchmark, constructorCopy,
Comparators.naturalOrder())) { 51 throw new Error("Copy
not equal"); 52 }
53 54 if (benchmark == jlaCopy) { 55 throw
new Error("should be different instances"); 56 } 57
if (!benchmark.equals(jlaCopy)) { 58 throw new
Error("Copy not equal"); 59 } 60 if (0 !=
Objects.compare(benchmark, jlaCopy, Comparators.naturalOrder())) { 61
throw new Error("Copy not equal"); 62 } 63 64
if (constructorCopy == jlaCopy) { 65 throw new
Error("should be different instances"); 66 } 67 if
(!constructorCopy.equals(jlaCopy)) { 68 throw new
Error("Copy not equal"); 69 } 70 if (0 !=
Objects.compare(constructorCopy, jlaCopy, Comparators.naturalOrder()))
{ 71 throw new Error("Copy not equal");
To check whether the jlaCopy is really taking the given char array by
reference, a test could also do something "illegal" like:
char[] array = benchmark.toCharArray();
String jlaCopy = jla.newStringUnsafe(array);
array[0] = "X"; // ouch!
String constructorCopy = new String(array);
if (!constructorCopy.equals(jlaCopy)) { ... }
Regards, Peter
2013/5/1 Mike Duigou <mike.dui...@oracle.com>
> Hello all;
>
> Since this code will be introduced without any usages I decided it was
> critical to make a stand alone unit test. I've updated the webrev:
>
> http://cr.openjdk.java.net/~mduigou/JDK-8013528/1/webrev/
>
> The webrev mistakes my hg copy for a rename... Ignore that. Capturing the
> provenance of the test file probably isn't critical since the file is
> repurposed for a different test, but I prefer to have the origin tracked
> rather than use a non-vcs copy.
>
> I also made the other changes suggested by reviewers.
>
> Thanks
>
> Mike
>
> On Apr 29 2013, at 21:30 , Mike Duigou wrote:
>
> > Hello all;
> >
> > This change originated as part of JDK-8006627 (which was also previously
> split into JDK-8007398 as well). It adds an internal mechanism for
> performance sensitive usages to create a string from a provided character
> array without copying that array. This saves both in the allocation (and
> subsequent GC) as well as the copying of the characters. There are a few
> places in the JDK that return Strings which can benefit from this change.
> >
> > http://cr.openjdk.java.net/~mduigou/JDK-8013528/0/webrev/
> >
> > Fear not, JDK-8006627 and JDK-8007398 will be revisited... For now it
> would be to get this change in to allow other potential users to move
> forward with their changes.
> >
> > Mike
>
>
