Java example source code file (Test3.java)

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Java - Java tags/keywords

list, serializable, util

The Test3.java Java example source code

/**
 * @test     /nodynamiccopyright/
 * @bug      7062745 7157798
 * @summary  Negative test of conflicting same-name methods inherited from multiple interfaces when return type not compatible
 * @compile/fail/ref=Test3.out -Werror -Xlint:unchecked -XDrawDiagnostics Test3.java
 */

import java.util.List;
import java.io.Serializable;

interface A { int m(); }
interface B { Integer m(); }

interface AB extends A, B {} //error

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

interface CD extends C, D {} //error

interface E<T> { T m(); }
interface F<T> { T m(); }
interface G { Serializable m(); }

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

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

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

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

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

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

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