1 /**

     2  * @test     /nodynamiccopyright/

     3  * @bug      7062745 7157798

     4  * @summary  Negative test of conflicting same-name methods inherited from multiple interfaces when return type not compatible

     5  * @compile/fail/ref=Test3.out -Werror -Xlint:unchecked -XDrawDiagnostics Test3.java

     6  */

     7 

     8 import java.util.List;

     9 import java.io.Serializable;

    10 

    11 interface A { int m(); }

    12 interface B { Integer m(); }

    13 

    14 interface AB extends A, B {} //error

    15 

    16 interface C { List<Integer> m(); }

    17 interface D { List<Number> m(); }

    18 

    19 interface CD extends C, D {} //error

    20 

    21 interface E<T> { T m(); }

    22 interface F<T> { T m(); }

    23 interface G { Serializable m(); }

    24 

    25 interface BE extends B, E<Number> {} //ok, covariant return

    26 

    27 interface BE2<T> extends B, E<T> {} //error

    28 

    29 interface EF<T> extends E<T>, F<T> {} //ok

    30 

    31 interface EF2<U, V extends U> extends E<U>, F<V> {} //ok, covariant return

    32 

    33 interface EF3<U, V> extends E<U>, F<V> {} //error

    34 

    35 interface EG<T extends Number> extends E<T>, G {} //ok

    36 

    37 interface EFG<U extends Serializable, V extends Serializable> extends E<U>, F<V>, G {} //error