RFR: 8364361: [process] java.lang.Process should implement close and be AutoCloseable [v4]

[Archie Cobbs]

On Tue, 19 Aug 2025 21:50:33 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:
> 
>   Revisited handling of IOExceptions to throw instead of completely ignoring or logging.

src/java.base/share/classes/java/lang/Process.java line 652:

> 650:      */
> 651:     public void close() throws IOException {
> 652:         synchronized(this) {

Might be safer to create a dedicated, private object to use for locking here instead of `this`. Otherwise there's a possibility of deadlock (or indefinite delay), for example, if a subclass happens to have a `synchronized` method that could block while trying to communicate with the process, etc.

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PR Review Comment: https://git.openjdk.org/jdk/pull/26649#discussion_r2286415567