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/*
* Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* @test
* @bug 8025290
* @summary javac implicit versus explicit lambda compilation error
* @compile ExplicitVSImplicitLambdaTest.java
*/
import java.util.function.*;
public class ExplicitVSImplicitLambdaTest {
private void test()
{
/* in the explicit case "e" is inferred to String so we can use a String
* only method.
*/
MyComparator.mycomparing1((String e) -> e.concat(""));
MyComparator.mycomparing2((String e) -> e.concat(""));
MyComparator.mycomparing3((String e) -> e.concat(""));
MyComparator.mycomparing4((String e) -> e.concat(""));
/* in the implicit case "e" is inferred to Object so toString() is OK.
*/
MyComparator.mycomparing1((e) -> e.toString());
MyComparator.mycomparing2((e) -> e.toString());
MyComparator.mycomparing3((e) -> e.toString());
MyComparator.mycomparing4((e) -> e.toString());
}
}
interface MyComparator<T> {
public static <T, U extends Comparable<? super U>> MyComparator<T> mycomparing1(
Function<? super T, ? extends U> keyExtractor) {
return null;
}
public static <T, U extends Comparable<? super U>> MyComparator<T> mycomparing2(
Function<? super T, ? super U> keyExtractor) {
return null;
}
public static <T, U extends Comparable<? super U>> MyComparator<T> mycomparing3(
Function<? extends T, ? extends U> keyExtractor) {
return null;
}
public static <T, U extends Comparable<? super U>> MyComparator<T> mycomparing4(
Function<? extends T, ? super U> keyExtractor) {
return null;
}
}
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