1 /* 2 * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /* 25 * @test 26 * @bug 8009736 8010279 27 * @run testng BasicTest 28 */ 29 30 import java.util.Comparator; 31 import java.util.function.BinaryOperator; 32 import java.util.function.Function; 33 import java.util.function.ToIntFunction; 34 import org.testng.annotations.Test; 35 36 37 import static java.util.function.BinaryOperator.minBy; 38 import static java.util.function.BinaryOperator.maxBy; 39 import static org.testng.Assert.assertSame; 40 import static org.testng.Assert.fail; 41 42 /** 43 * Unit tests for helper methods in Comparators 44 */ 45 @Test(groups = "unit") 46 public class BasicTest { 47 48 private static class People { 49 final String firstName; 50 final String lastName; 51 final int age; 52 53 People(String first, String last, int age) { 54 firstName = first; 55 lastName = last; 56 this.age = age; 57 } 58 59 String getFirstName() { return firstName; } 60 String getLastName() { return lastName; } 61 int getAge() { return age; } 62 } 63 64 private final People people[] = { 65 new People("John", "Doe", 34), 66 new People("Mary", "Doe", 30), 67 }; 68 69 public void testMaxBy() { 70 Comparator<People> cmp = Comparator.comparing(People::getFirstName); 71 // lesser 72 assertSame(maxBy(cmp).apply(people[0], people[1]), people[1]); 73 // euqal 74 cmp = Comparator.comparing(People::getLastName); 75 assertSame(maxBy(cmp).apply(people[0], people[1]), people[0]); 76 // greater 77 cmp = Comparator.comparingInt(People::getAge); 78 assertSame(maxBy(cmp).apply(people[0], people[1]), people[0]); 79 } 80 81 public void testMinBy() { 82 Comparator<People> cmp = Comparator.comparing(People::getFirstName); 83 // lesser 84 assertSame(minBy(cmp).apply(people[0], people[1]), people[0]); 85 // euqal 86 cmp = Comparator.comparing(People::getLastName); 87 assertSame(minBy(cmp).apply(people[0], people[1]), people[0]); 88 // greater 89 cmp = Comparator.comparingInt(People::getAge); 90 assertSame(minBy(cmp).apply(people[0], people[1]), people[1]); 91 } 92 93 public void testNulls() { 94 try { 95 BinaryOperator<String> op = minBy(null); 96 fail("minBy(null) should throw NPE"); 97 } catch (NullPointerException npe) {} 98 99 try { 100 BinaryOperator<String> op = maxBy(null); 101 fail("maxBy(null) should throw NPE"); 102 } catch (NullPointerException npe) {} 103 } 104 }