On 10/21/2013 08:16 PM, Joe Darcy wrote:
Hello,
Earlier in JDK 8, various core library classes were annotated with the
@FunctionalInterface annotation (JDK-8005623 Retrofit
FunctionalInterface annotations to core platform interfaces). As
experience has been gained with the feature, the time has come to
revisit some of those annotations under issue
JDK-8022658: Revisit FunctionalInterface on some core libs types
In brief, I propose removing @FunctionalInterface from the following
six types:
src/share/classes/java/io/Closeable.java
src/share/classes/java/io/Flushable.java
src/share/classes/java/lang/AutoCloseable.java
src/share/classes/java/lang/Comparable.java
src/share/classes/java/lang/Iterable.java
src/share/classes/java/lang/Readable.java
In these cases, the single method of the interface is more so a
mix-in/trait like feature and not readily usable standalone in a
lambda expression. Patch below.
Thanks,
-Joe
As a design note, the real way to avoid lambda conversion is to replace
the abstract method by a default method that
throws a runtime exception.
I don't propose to do that here :)
cheers,
Rémi
