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/*
* Copyright (c) 2011, 2014, 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 8003280
* @summary Add lambda tests
* Test lambda expressions for existing SAM interfaces like Runnable and Comparator<T>
* @compile LambdaTest1.java
* @run main LambdaTest1
*/
import java.util.Collections;
import java.util.List;
import java.util.ArrayList;
public class LambdaTest1 {
private static String assertionStr = "";
private static void assertTrue(boolean b) {
if(!b)
throw new AssertionError();
}
private static void test1(Runnable r) {
r.run();
}
void test2(Object o) {
if(o instanceof Runnable)
((Runnable)o).run();
}
Runnable test3() {
return ()-> { assertionStr += "Runnable6"; };
}
public static void main(String[] args) {
//lambda expressions for SAM interface Runnable:
//assign:
Runnable r = ()-> { assertionStr += "Runnable1 "; };
r.run();
//cast:
((Runnable)()-> { assertionStr += "Runnable2 "; }).run();
Object o = (Runnable)()-> {};
o = (Runnable)()-> {
switch (assertionStr) {
case "Runnable1 Runnable2 ":
assertionStr += "Runnable3 ";
break;
default:
throw new AssertionError();
}
return;
};
//method parameter:
test1(()-> { assertionStr += "Runnable4 "; return; });
LambdaTest1 test = new LambdaTest1();
test.test2((Runnable)()-> { assertionStr += "Runnable5 "; });
//return type:
r = test.test3();
r.run();
assertTrue(assertionStr.equals("Runnable1 Runnable2 Runnable4 Runnable5 Runnable6"));
//lambda expressions for SAM interface Comparator<T>:
List<Integer> list = new ArrayList<Integer>();
list.add(4);
list.add(10);
list.add(-5);
list.add(100);
list.add(9);
Collections.sort(list, (Integer i1, Integer i2)-> i2 - i1);
String result = "";
for(int i : list)
result += i + " ";
assertTrue(result.equals("100 10 9 4 -5 "));
Collections.sort(list,
(i1, i2) -> {
String s1 = i1.toString();
String s2 = i2.toString();
return s1.length() - s2.length();
});
result = "";
for(int i : list)
result += i + " ";
assertTrue(result.equals("9 4 10 -5 100 "));
}
}
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