On Sun, 28 Apr 2024 09:54:34 GMT, Viktor Klang <vkl...@openjdk.org> wrote:
> Primarily offering this PR for discussion, as Throwables throwing exceptions > on toString(), getLocalizedMessage(), or getMessage() seems like a rather > unreasonable thing to do. > > Nevertheless, there is some things we can do, as witnessed in this PR. src/java.base/share/classes/java/util/concurrent/CompletableFuture.java line 352: > 350: return wrapping; > 351: } > 352: This is the main thing—and the big question is if this approach is the best path or not. src/java.base/share/classes/java/util/concurrent/CompletableFuture.java line 2653: > 2651: * its completion state. The state, in brackets, contains the > 2652: * String {@code "Completed normally"} or the String {@code > 2653: * "Completed exceptionally"}, or the String {@code "Not These two looks like a discrepancy between spec and implementation, and it seemed safer to amend the spec rather than the implementation, as code might be relying on *actual behavior* rather than the spec:ed one. @DougLea You might have some thoughts to offer on this :) src/java.base/share/classes/java/util/concurrent/CompletableFuture.java line 2670: > 2668: : "[Not completed, " + count + " dependents]") > 2669: : (((r instanceof AltResult) && ((AltResult)r).ex != null) > 2670: ? "[Completed exceptionally: " + > ((AltResult)r).ex.getClass().getName() + "]" @DougLea @AlanBateman It seemed safer to switch to outputting the cause FQCN rather than wrapping in a try-catch and trying to come up with a fallback text. The reason for amending this is for things like JShell, results are toString():ed which would mean that the current session would break if toString():ing the result throws (also further signalling that throwing on toString() seems unreasonable in general). test/jdk/java/util/concurrent/tck/CompletableFutureTest.java line 87: > 85: // even if thrown exceptions end up throwing exceptions from > their String > 86: // representations. > 87: @Override public String getMessage() { I decided to do this to make sure that *all pre-existing test cases* would still work even if the exception used has a misbehaving toString() (toString() transitively calls getLocalizedMessage() which in turn calls getMessage()) ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/18988#discussion_r1582075756 PR Review Comment: https://git.openjdk.org/jdk/pull/18988#discussion_r1582075209 PR Review Comment: https://git.openjdk.org/jdk/pull/18988#discussion_r1582075561 PR Review Comment: https://git.openjdk.org/jdk/pull/18988#discussion_r1582075630