Java example source code file (Neg04.java)

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Java - Java tags/keywords

ia1, ia2, integer, neg04, number

The Neg04.java Java example source code

/* @test /nodynamiccopyright/
 * @bug 7192246
 * @summary check that default method must have most specific return type
 * @compile/fail/ref=Neg04.out -XDrawDiagnostics Neg04.java
 */

class Neg04 {
    interface IA1 { Integer m(); }
    interface IA2 extends IA1 { default Number m() { return Neg04.m(this); } } //error

    abstract class C implements IA1, IA2 {}

    static int m(IA2 a) { return 0; }
}