> 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
Jorn Vernee has updated the pull request incrementally with one additional commit since the last revision: Use AccessType ordinal in guard checks instead of the AccessMode ordinal ------------- Changes: - all: https://git.openjdk.java.net/jdk/pull/843/files - new: https://git.openjdk.java.net/jdk/pull/843/files/16d9fd0e..8e5fb451 Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=843&range=07 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=843&range=06-07 Stats: 164 lines in 3 files changed: 0 ins; 0 del; 164 mod Patch: https://git.openjdk.java.net/jdk/pull/843.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/843/head:pull/843 PR: https://git.openjdk.java.net/jdk/pull/843