RFR: 8361972: Clarify the condition of System.console() about standard input/output [v3]

[Stuart Marks]

On Mon, 14 Jul 2025 20:58:56 GMT, Justin Lu <jlu at openjdk.org> wrote:

>> Naoto Sato has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision:
>> 
>>  - Wording change, isTerminal() always returns true
>>  - Merge branch 'master' into JDK-8361972-System-console-condition
>>  - Wording modification
>>  - initial commit
>
> src/java.base/share/classes/java/io/Console.java line 47:
> 
>> 45:  * output streams then its console will exist and will typically be
>> 46:  * connected to the keyboard and display from which the virtual machine
>> 47:  * was launched.  If the virtual machine is started automatically, for
> 
> I think it might read easier if we reword the structure of the sentence to make it more concise.
> 
> E.g.
> 
>> The virtual machine may not have a console if started automatically, (e.g., by a background scheduler) or if either the standard input or output has been redirected.

I took another look at this and I agree that some rewording is necessary. There are several inconsistencies in the wording here, e.g., between "exists / does not exist" or "the virtual machine has a console / does not have a console" or "a console / a console device". I rewrote the first couple paragraphs here to unify the wording around a console as a noun (that is, no "console device") and to use "exists / does not exist" consistently. I also made some areas a bit more definite.

    * <p> Whether a virtual machine's console exists is dependent upon the
    * underlying platform and also upon the manner in which the virtual
    * machine is invoked.  If the virtual machine is started from an
    * interactive command line without redirecting the standard input and
    * output streams, then its console will generally exist and will be
    * connected to the keyboard and display from which the virtual machine
    * was launched. If the standard input or standard output have been
    * redirected (for example, to a file or to a pipe), or if the virtual
    * machine was started from a background job scheduler, the console
    * will not exist.
    * <p>
    * If the console exists, then it is represented by a unique instance of this
    * class which can be obtained by invoking the {@link System#console()} method.
    * If the console does not exist, that method will return {@code null}.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/26299#discussion_r2289573821