RFR: 8364361: [process] java.lang.Process should implement Closeable [v14]

[Alan Bateman]

On Wed, 1 Oct 2025 17:45:41 GMT, Roger Riggs <rriggs at openjdk.org> wrote:

>> The teardown of a Process launched by `ProcessBuilder` includes the closing of streams and ensuring the termination of the process is the responsibility of the caller. The `Process.close()` method provides a clear and obvious way to ensure all the streams are closed and the process terminated.
>> 
>> The try-with-resources statement is frequently used to open streams and ensure they are closed on exiting the block. By implementing `AutoClosable.close()` the completeness of closing the streams and process termination can be done by try-with-resources.
>> 
>> The actions of the `close()` method are to close each stream and destroy the process if it has not terminated.
>
> Roger Riggs has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Clarify the use of waitFor after close() or T-W-R exit.

src/java.base/share/classes/java/lang/Process.java line 182:

> 180:      * Close all writer and reader streams and terminate the process.
> 181:      * The streams are closed immediately and the process is terminated without waiting.
> 182:      * This method is idempotent, if the process has already been closed

I think make this `{@code Process}` as that is the handle to the process (the process has terminated, it hasn't been closed, if you see what I mean).

src/java.base/share/classes/java/lang/Process.java line 185:

> 183:      * invoking this method has no effect.
> 184:      * <p>
> 185:      * If the data from the process streams is needed, it must be read before calling this method.

The process streams includes the output stream so it might be a bit better to say ".. data from the input or error streams are needed".

src/java.base/share/classes/java/lang/Process.java line 186:

> 184:      * <p>
> 185:      * If the data from the process streams is needed, it must be read before calling this method.
> 186:      * The contents of streams that have not been read fully are lost, they are discarded or ignored.

"read fully", have you considered read to end of stream?

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PR Review Comment: https://git.openjdk.org/jdk/pull/26649#discussion_r2403783569
PR Review Comment: https://git.openjdk.org/jdk/pull/26649#discussion_r2403783966
PR Review Comment: https://git.openjdk.org/jdk/pull/26649#discussion_r2403784104