RFR: 8072379: Implement jdk.Version and jdk.OracleVersion

[Iris Clark]

Hi, Joe, Roger, Alan, Magnus, and Mandy.

At the end of December (shortly before the Christmas/Winter 
break and my vacation), I provided responses to your messages 
and an updated webrev:

  http://cr.openjdk.java.net/~iris/verona/8072379/webrev.2/

I didn't hear from anybody, so I'd like to optimistically assume
that you were satisfied.  Is that correct? 

For you convenience, here's a reference to the December and November
threads:

    http://mail.openjdk.java.net/pipermail/core-libs-dev/2015-December/037062.html
    http://mail.openjdk.java.net/pipermail/core-libs-dev/2015-November/036904.html

I'd like to wrap up this work for the initial implementation of 
jdk.Version soon.  

Regards,
iris

-----Original Message-----
From: Iris Clark 
Sent: Friday, December 18, 2015 1:55 PM
To: Joe Darcy; Mandy Chung
Cc: core-libs-dev at openjdk.java.net; verona-dev at openjdk.java.net
Subject: RE: RFR: 8072379: Implement jdk.Version and jdk.OracleVersion

Hi, Joe.

Thanks for the review comments.

>>>     http://cr.openjdk.java.net/~irisa/verona/8072379/webrev.1/

> Is the intention that downstream JDK distributions, such as IcedTea, 
> whether based on OpenJDK or otherwise, would provide their own 
> specialization of the jdk.Version class?

No.  Downstream users may provide their own specialization, but there is no requirement that they must do so. 

jdk.OracleVersion has been removed.  The functionality it provided, access to the fourth element of the version number, is trivially accessed by existing methods in jdk.Version.

I've filed the following bug to address the more general use case:

    8145793:  Provide vendor-specific interpretation of a JDK version string
    https://bugs.openjdk.java.net/browse/JDK-8145793

> The equals / hashCode behavior of Version and OracleVersion is bit 
> surprising and I think somewhat underspecified given the possibility 
> of defining subclasses.

Given the above regarding downstream use, I've make jdk.Version final and the constructor is now private.  Oracle or any other JDK distribution wishing to impose additional semantics to the version string interpretation will need to do so via encapsulation rather than inheritance.

> How is this API supposed to behave if the component version strings 
> have a numerical value greater than Integer.MAX_VALUE?

>From the specification of the only instance method, Version.parse():

     * @throws  NumberFormatException 
     *          If an element of the version number or the build number cannot
     *          be represented as an {@link Integer}

> Was using Longs to record numerical versions rather than Integers 
> considered?

Yes.  In an informal poll conducted during implementation, it was thought that 2^32 bits would be more than sufficient to represent the components of typical version numbers.

An updated webrev is forthcoming.

Thanks,
iris

PS:  I believe that we are both out the week of 21 December, so I don't expect to hear back from you until the New Year.