Tue, 14 May 2013 11:11:09 -0700
8012556: Implement lambda methods on interfaces as static
8006140: Javac NPE compiling Lambda expression on initialization expression of static field in interface
Summary: Lambdas occurring in static contexts or those not needing instance information should be generated into static methods. This has long been the case for classes. However, as a work-around to the lack of support for statics on interfaces, interface lambda methods have been generated into default methods. For lambdas in interface static contexts (fields and static methods) this causes an NPE in javac because there is no 'this'. MethodHandles now support static methods on interfaces. This changeset allows lambda methods to be generated as static interface methods. An existing bug in Hotspot (8013875) is exposed in a test when the "-esa" flag is used. This test and another test that already exposed this bug have been marked with @ignore.
Reviewed-by: mcimadamore
mcimadamore@1415 | 1 | /* |
mcimadamore@1415 | 2 | * @test /nodynamiccopyright/ |
mcimadamore@1415 | 3 | * @bug 8003280 |
mcimadamore@1415 | 4 | * @summary Add lambda tests |
mcimadamore@1415 | 5 | * This test is for identifying a non-SAM type: Having more than one methods due to inheritance, and none of them has a subsignature of all other methods |
mcimadamore@1415 | 6 | * @compile/fail/ref=NonSAM2.out -XDrawDiagnostics NonSAM2.java Helper.java |
mcimadamore@1415 | 7 | */ |
mcimadamore@1415 | 8 | |
mcimadamore@1415 | 9 | import java.util.List; |
mcimadamore@1415 | 10 | |
mcimadamore@1415 | 11 | interface Foo1 { int getAge(String s);} |
mcimadamore@1415 | 12 | interface Bar1 { Integer getAge(String s);} |
mcimadamore@1415 | 13 | interface Foo1Bar1 extends Foo1, Bar1 {} //types Bar1 and Foo1 are incompatible; both define getAge(String), but with unrelated return types |
mcimadamore@1415 | 14 | |
mcimadamore@1415 | 15 | interface AC extends A, C {} //name clash: getOldest(List<?>) in C and getOldest(List<Number>) in A have the same erasure, yet neither overrides the other |
mcimadamore@1415 | 16 | interface ABC extends A, B, C {} //name clash: getOldest(List<?>) in C and getOldest(List<Number>) in A have the same erasure, yet neither overrides the other |
mcimadamore@1415 | 17 | interface AD extends A, D {} //name clash: getOldest(List<Integer>) in D and getOldest(List<Number>) in A have the same erasure, yet neither overrides the other |
mcimadamore@1415 | 18 | |
mcimadamore@1415 | 19 | interface Foo2<T> { void m(T arg);} |
mcimadamore@1415 | 20 | interface Bar2<S> { void m(S arg);} |
mcimadamore@1415 | 21 | interface Foo2Bar2<T1, T2> extends Foo2<T1>, Bar2<T2> {} //name clash: m(S) in Bar and m(T) in Foo have the same erasure, yet neither overrides the other |