> This proposes a new static `Proxy::invokeDefaultMethod` method to invoke > the given default method on the given proxy instance. > > The implementation looks up a method handle for `invokespecial` instruction > as if called from with the proxy class as the caller, equivalent to calling > `X.super::m` where `X` is a proxy interface of the proxy class and > `X.super::m` will resolve to the specified default method. > > The implementation will call a private static `proxyClassLookup(Lookup > caller)` > method of the proxy class to obtain its private Lookup. This private method > in the proxy class only allows a caller Lookup on java.lang.reflect.Proxy > class > with full privilege access to use, or else `IllegalAccessException` will be > thrown. > > This patch also proposes to define a proxy class in an unnamed module to > a dynamic module to strengthen encapsulation such that they are only > unconditionally exported from a named module but not open for deep reflective > access. This only applies to the case if all the proxy interfaces are public > and in a package that is exported or open. > > One dynamic module is created for each class loader that defines proxies. > The change changes the dynamic module to contain another package (same > name as the module) that is unconditionally exported and is opened to > `java.base` only. > > There is no change to the package and module of the proxy class for > the following cases: > > - if at least one proxy interface is non-public, then the proxy class is > defined > in the package and module of the non-public interfaces > - if at least one proxy is in a package that is non-exported and non-open, > if all proxy interfaces are public, then the proxy class is defined in > a non-exported, non-open package of a dynamic module. > > The spec change is that a proxy class used to be defined in an unnamed > module, i.e. in a exported and open package, is defined in an unconditionally > exported but non-open package. Programs that assume it to be open > unconditionally > will be affected and cannot do deep reflection on such proxy classes. > > Peter Levart contributed an initial prototype [1] (thanks Peter). I think > the exceptions could be simplified as more checking should be done prior to > the invocation of the method handle like checking the types of the arguments > with the method type. This approach avoids defining a public API > `protected Proxy::$$proxyClassLookup$$` method. Instead it defines a > private static method that is restricted for Proxy class to use (by > taking a caller parameter to ensure it's a private lookup on Proxy class). > > javadoc/specdiff: > http://cr.openjdk.java.net/~mchung/jdk16/webrevs/8159746/api/ > http://cr.openjdk.java.net/~mchung/jdk16/webrevs/8159746/specdiff/ > > [1] > http://mail.openjdk.java.net/pipermail/core-libs-dev/2016-June/041629.html
Mandy Chung has updated the pull request incrementally with one additional commit since the last revision: Performance improvement contributed by plevart ------------- Changes: - all: https://git.openjdk.java.net/jdk/pull/313/files - new: https://git.openjdk.java.net/jdk/pull/313/files/8352a20b..d443f10e Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=313&range=05 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=313&range=04-05 Stats: 24 lines in 4 files changed: 7 ins; 8 del; 9 mod Patch: https://git.openjdk.java.net/jdk/pull/313.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/313/head:pull/313 PR: https://git.openjdk.java.net/jdk/pull/313
