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Build Identifier: 20100617-1415 The method <fails> in the following does not compile, resulting in "Bound mismatch: The generic method fails(E) of type ServiceUtils is not applicable for the arguments (OwnedEntity<Integer,Entity<Integer>>). The inferred type Entity<Integer> is not a valid substitute for the bounded parameter <O extends Entity<L>>" Whereas the method <works> does. Both compile under javac public class Service { public void fails(OwnedEntity<Integer, Entity<Integer>> entity) { ServiceUtils.fails(entity); } public void works(OwnedEntity<Integer, Entity<Integer>> entity, Integer dummy) { ServiceUtils.works(entity, dummy); } } public class Entity<K extends Serializable> { K key; } public class OwnedEntity<K extends Serializable, O extends Entity<? extends Serializable>> extends Entity<K> { O owner; } public class ServiceUtils { public static <E extends OwnedEntity<K, O>, K extends Serializable, O extends Entity<L>, L extends Serializable> void fails( E entity) { } public static <E extends OwnedEntity<K, O>, K extends Serializable, O extends Entity<L>, L extends Serializable> void works( E entity, L dummy) { } } Reproducible: Always Steps to Reproduce: 1. Attempt to compile
Srikanth, please investigate.
See that this code does not compile with JDK7. javac 7b147 complains: X.java:7: error: invalid inferred types for K,O,L; inferred type does not confor m to declared bound(s) ServiceUtils.fails(entity); ^ inferred: Entity<Integer> bound(s): Entity<Serializable> where K,E,O,L are type-variables: K extends Serializable declared in method <E,K,O,L>fails(E) E extends OwnedEntity<K,O> declared in method <E,K,O,L>fails(E) O extends Entity<L> declared in method <E,K,O,L>fails(E) L extends Serializable declared in method <E,K,O,L>fails(E) 1 error While eclipse complains: Bound mismatch: The generic method fails(E) of type ServiceUtils is not applicable for the arguments (OwnedEntity<Integer,Entity<Integer>>). The inferred type Entity<Integer> is not a valid substitute for the bounded parameter <O extends Entity<L>> against the simplified test case below which can be cut & pasted into a single file: //--------------------------------------------------- import java.io.Serializable; public class X { public void fails(OwnedEntity<Integer, Entity<Integer>> entity) { ServiceUtils.fails(entity); } public void works(OwnedEntity<Integer, Entity<Integer>> entity, Integer dummy) { ServiceUtils.works(entity, dummy); } } class Entity<K extends Serializable> { K key; } class OwnedEntity<K extends Serializable, O extends Entity<? extends Serializable>> extends Entity<K> { O owner; } class ServiceUtils { public static <E extends OwnedEntity<K, O>, K extends Serializable, O extends Entity<L>, L extends Serializable> void fails( E entity) { } public static <E extends OwnedEntity<K, O>, K extends Serializable, O extends Entity<L>, L extends Serializable> void works( E entity, L dummy) { } } // --------------------------------------------------------------- Since eclipse behavior matches the latest javac behavior, I conclude that this was a bug in JDK5,6 compilers which has since been fixed. Closing this as INVALID.
Verified for 3.8M4
