JDK 8: Second Release Candidate

[Martijn Verburg]

Hi Brenden,

Thanks for reporting this issue, but it should be submitted via bugs.sun.com:-).

Cheers,
Martijn


On 14 February 2014 18:54, Brenden Towey <brendentowey at gmail.com> wrote:

> I'd like to make a bug report.  Java has had for a while now a bug in its
> regex system which I'd like to see fixed.
>
> The short of it is that the \z pattern does not return 'requiresEnd' and
> it should.
>
>    public void endTest()
>    {
>       Matcher m = Pattern.compile( "\\z" ).matcher( "" );
>       m.find();
>       System.out.println( m.requireEnd() );
>       assert ( m.requireEnd() );
>    }
>
> This prints 'false'.  It shouldn't take much thought to convince yourself
> that if the end of input is required, then 'requiresEnd()' should always be
> true.  There's never a case for the \z pattern that you want to match less
> than all of input.  The above code snippet would make a fine unit test for
> this bug, btw.
>
> You can see the results of this bug if you use other parts of the API, for
> example java.util.Scanner.  Since the the requiresEnd() method always
> returns false, the Scanner will match its own internal buffer (usually 1024
> characters) and not the end of input.
>
>
>    public void demo()
>    {
>       StringBuilder str = new StringBuilder( 4 * 1024 );
>       for( int i = 0; i < 1024; i++ ) {
>          str.append( i );
>          str.append( ',' );
>       }
>       Scanner s = new Scanner( str.toString() );
>       String result = s.useDelimiter( "\\z" ).next();
>       String expected = str.toString();
>       System.out.println( result.length()+", "+expected.length() );
>       assert( expected.equals( result ) );
>    }
>
> Output:
> C:\Users\Brenden\Dev\proj\Test2\build\classes>java -version
> java version "1.8.0"
> Java(TM) SE Runtime Environment (build 1.8.0-b129)
> Java HotSpot(TM) 64-Bit Server VM (build 25.0-b69, mixed mode)
>
> C:\Users\Brenden\Dev\proj\Test2\build\classes>java -cp .
> quicktest.RegexBug
> 1024, 4010
>
> You can see that the length of the matched string is 1024, not 4010 from
> the original string.
>
> Finally, if you need more convincing, you can test the \Z (capital Z)
> pattern, which does essentially the same thing as \z.  \Z always sets its
> requiresEnd() flag, and it works as expected in the tests above.
>
> Summary: \z should always set its 'requiresEnd' flag.
>
> Thanks for taking the time to read this!
>
>
>
> On 2/11/2014 2:31 PM, mark.reinhold at oracle.com wrote:
>
>> Last week a serious flaw in a new API was reported [1].  We decided to
>> fix that bug, along with an unrelated JCK failure on Mac OS X [2], so
>> we now have a second JDK 8 Release Candidate, build 129.
>>
>> Binaries available here, as usual: https://jdk8.java.net/download.html
>>
>>
>>
>
>