RFR: 8209937: Enhance java.io.Console - provide methods to query console width and height

[Peter Levart]

On 08/24/2018 03:18 PM, Langer, Christoph wrote:
> Hi Rémi, Hi Peter,
>
> thanks for your quick answers.
>
> What you've suggested, Rémi, is perfectly right. I've updated my webrev. The methods were copied from our old implementation (of a different class) where they were provided as static.
>
> I will also think of using an optional. I'm furthermore wondering if we should provide a method "dimensions()" returning an (optional) java.io.Console.Dimension object that contains both height and width...

Yes, a good idea. In AWT/Swing such methods are called getSize() or size():

     /**
      * @deprecated As of JDK version 1.1,
      * replaced by <code>getSize()</code>.
      */
     @Deprecated
     public Dimension size() {
         return new Dimension(width, height);
     }

It seems that at some stage, methods like size() have been @Deprecated 
and replaced with getSize(). Now we're going back from getSize() to 
size() as the preferred name...

I suggest you create a private native method that returns both 
dimensions (encoded in a jlong for example, with non-existence being 
-1L) and then do the conversion (to Optional<Console.Dimension>) in a 
public Java method. It would be much simpler than creating objects in 
native code...

Regards, Peter

>
> Here is a new webrev: http://cr.openjdk.java.net/~clanger/webrevs/8209937.1/
>
> Best regards
> Christoph
>
>> -----Original Message-----
>> From: Peter Levart <peter.levart at gmail.com>
>> Sent: Freitag, 24. August 2018 13:06
>> To: Remi Forax <forax at univ-mlv.fr>; Langer, Christoph
>> <christoph.langer at sap.com>
>> Cc: core-libs-dev <core-libs-dev at openjdk.java.net>; Baesken, Matthias
>> <matthias.baesken at sap.com>
>> Subject: Re: RFR: 8209937: Enhance java.io.Console - provide methods to
>> query console width and height
>>
>>
>>
>> On 08/24/2018 12:09 PM, Remi Forax wrote:
>>> Hi Christoph,
>>> getWidth() and getHeight() should be instance methods and not static
>> methods, providing the weight or the height if there is no console seems
>> weird.
>>> Also, they should be named width() and height() given the rest of the
>> methods of java.io.Console doesn't use the "get" convention.
>>> regards,
>>> Rémi
>> They could also return OptionalInt to force user to think about
>> "not-available" situations.
>>
>> Regards, Peter
>>
>>> ----- Mail original -----
>>>> De: "Christoph Langer" <christoph.langer at sap.com>
>>>> À: "core-libs-dev" <core-libs-dev at openjdk.java.net>
>>>> Cc: "Baesken, Matthias" <matthias.baesken at sap.com>
>>>> Envoyé: Vendredi 24 Août 2018 11:33:05
>>>> Objet: RFR: 8209937: Enhance java.io.Console - provide methods to query
>> console width and height
>>>> Hi,
>>>>
>>>> please review and give feedback for this augmentation of java.io.Console.
>>>>
>>>> We have users that have the need to query for Width and Height of the
>> console
>>>> device in Java. In our own JVM implementation we had given them this
>> hook as a
>>>> custom extension already quite some time ago. We think, however, that
>> it is a
>>>> worthwhile augmentation of java.io.Console.
>>>>
>>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8209937
>>>> Webrev: http://cr.openjdk.java.net/~clanger/webrevs/8209937.0/
>>>>
>>>> I'll also open a CSR for this, but I'll wait for some feedback on our proposal
>>>> first.
>>>>
>>>> Thanks & Best regards
>>>> Christoph