Saturday, June 9, 2018

Thread Methods destroy() and stop(Throwable) Removed in JDK 11

The message "RFR(s): 8204243: remove Thread.destroy() and Thread.stop(Throwable)" by @DrDeprecator (Stuart Marks) on the core-libs-dev OpenJDK mailing list is a request for review (RFR) of a change set associated with JDK-8204243 ["remove Thread.destroy() and Thread.stop(Throwable)"]. Both the bug report and the mailing list message describe the history of these two referenced Thread methods and explain that neither method really does anything useful.

The JDK 10 Javadoc API documentation for java.lang.Thread shows six methods on the Thread class that are deprecated, three of which are explicitly marked for removal. The table below summarizes these deprecated Thread methods.

Methods Deprecated in java.lang.Thread as of JDK 10
JDK 10
countStackFrames() 1.2 Yes Depends on deprecated suspend()
destroy() 1.5 Yes Throws NoSuchMethodError since inception
(never implemented)
resume() 1.2 No "Exists solely for use with suspend()"
stop() 1.2 No "This method is inherently unsafe."
stop(Throwable) 1.2 Yes Throws UnsupportedOperationException since JDK 8
suspend() 1.2 No "This method ... is inherently deadlock-prone."

It now appears that two of the three Thread methods that are deprecated and marked for removal will be removed with JDK 11. Both methods Thread.destroy() and Thread.stop(Throwable) should be completely removed as of JDK 11. The destroy() method has never done anything except throw the NoSuchMethodError and the stop(Throwable) method hasn't done anything except throw UnsupportedOperationException since JDK 8. Good riddance to these methods!

Additional References

1 comment:

@DustinMarx said...

It turns out that there are some "negative ramifications" of these methods being removed as documented on the Java subreddit. :)