On Fri, 23 Oct 2020 17:47:36 GMT, Jorn Vernee <jver...@openjdk.org> wrote:
> Hi, > > This patch adds an asExact() combinator to VarHandle, that will return a new > VarHandle that performs exact type checks, similar to > MethodHandle::invokeExact, to help developers catch inexact VarHandle usage, > which can lead to performance degradation. > > This is implemented using a boolean flag in VarForm. If the flag is set, the > exact type of the invocation is checked against the exact type in the > VarForm. If there is a mismatch, a WrongMethodTypeException is thrown. > > Other than that, there is also an asGeneric() combinator added that does the > inverse operation (thanks to Rémi for the suggestion). I've also added The > `@Hidden` annotation to the VarHandleGuards methods, as well as a > type-checking helper method called from the generic invocation lambda form, > so that the stack trace we get points at the location where the VarHandle is > being used. > > Thanks, > Jorn > > CSR link: https://bugs.openjdk.java.net/browse/JDK-8255375 This pull request has now been integrated. Changeset: 0a41ca6b Author: Jorn Vernee <jver...@openjdk.org> URL: https://git.openjdk.java.net/jdk/commit/0a41ca6b Stats: 1668 lines in 12 files changed: 1263 ins; 62 del; 343 mod 8254354: Add a withInvokeExactBehavior() VarHandle combinator Reviewed-by: psandoz, chegar ------------- PR: https://git.openjdk.java.net/jdk/pull/843
