Mercurial > hg > openjdk > jigsaw > jdk
changeset 7284:d8cae0195fe9
8010279: java.util.Stream.min/max((Comparator)null) is not consistent in throwing (unspecified) NPE
Reviewed-by: alanb, mduigou
| author | henryjen |
|---|---|
| date | Fri, 12 Apr 2013 12:41:18 -0700 |
| parents | 729ca1ef7c75 |
| children | 06dfdfa8c3e6 |
| files | src/share/classes/java/util/Comparators.java test/java/util/Comparators/BasicTest.java test/java/util/ComparatorsTest.java |
| diffstat | 3 files changed, 414 insertions(+), 353 deletions(-) [+] |
line wrap: on
line diff
--- a/src/share/classes/java/util/Comparators.java Fri Apr 12 12:12:53 2013 -0700 +++ b/src/share/classes/java/util/Comparators.java Fri Apr 12 12:41:18 2013 -0700 @@ -261,6 +261,7 @@ * according to the supplied {@code Comparator} */ public static<T> BinaryOperator<T> lesserOf(Comparator<? super T> comparator) { + Objects.requireNonNull(comparator); return (a, b) -> comparator.compare(a, b) <= 0 ? a : b; } @@ -274,6 +275,7 @@ * according to the supplied {@code Comparator} */ public static<T> BinaryOperator<T> greaterOf(Comparator<? super T> comparator) { + Objects.requireNonNull(comparator); return (a, b) -> comparator.compare(a, b) >= 0 ? a : b; } }
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/test/java/util/Comparators/BasicTest.java Fri Apr 12 12:41:18 2013 -0700 @@ -0,0 +1,412 @@ +/* + * Copyright (c) 2012, 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 8001667 8010279 + * @run testng BasicTest + */ + +import java.util.Comparator; +import java.util.Comparators; +import java.util.AbstractMap; +import java.util.Map; +import org.testng.annotations.Test; + +import java.util.function.BinaryOperator; +import java.util.function.Function; +import java.util.function.ToIntFunction; +import java.util.function.ToLongFunction; +import java.util.function.ToDoubleFunction; + +import static org.testng.Assert.assertEquals; +import static org.testng.Assert.assertTrue; +import static org.testng.Assert.assertSame; +import static org.testng.Assert.fail; + +/** + * Unit tests for helper methods in Comparators + */ +@Test(groups = "unit") +public class BasicTest { + private static class Thing { + public final int intField; + public final long longField; + public final double doubleField; + public final String stringField; + + private Thing(int intField, long longField, double doubleField, String stringField) { + this.intField = intField; + this.longField = longField; + this.doubleField = doubleField; + this.stringField = stringField; + } + + public int getIntField() { + return intField; + } + + public long getLongField() { + return longField; + } + + public double getDoubleField() { + return doubleField; + } + + public String getStringField() { + return stringField; + } + } + + private final int[] intValues = { -2, -2, -1, -1, 0, 0, 1, 1, 2, 2 }; + private final long[] longValues = { -2, -2, -1, -1, 0, 0, 1, 1, 2, 2 }; + private final double[] doubleValues = { -2, -2, -1, -1, 0, 0, 1, 1, 2, 2 }; + private final String[] stringValues = { "a", "a", "b", "b", "c", "c", "d", "d", "e", "e" }; + private final int[] comparisons = { 0, -1, 0, -1, 0, -1, 0, -1, 0 }; + + private<T> void assertComparisons(T[] things, Comparator<T> comp, int[] comparisons) { + for (int i=0; i<comparisons.length; i++) { + assertEquals(comparisons.length + 1, things.length); + assertEquals(comparisons[i], comp.compare(things[i], things[i+1])); + assertEquals(-comparisons[i], comp.compare(things[i+1], things[i])); + } + } + + public void testIntComparator() { + Thing[] things = new Thing[intValues.length]; + for (int i=0; i<intValues.length; i++) + things[i] = new Thing(intValues[i], 0L, 0.0, null); + Comparator<Thing> comp = Comparators.comparing(new ToIntFunction<BasicTest.Thing>() { + @Override + public int applyAsInt(Thing thing) { + return thing.getIntField(); + } + }); + + assertComparisons(things, comp, comparisons); + } + + public void testLongComparator() { + Thing[] things = new Thing[longValues.length]; + for (int i=0; i<longValues.length; i++) + things[i] = new Thing(0, longValues[i], 0.0, null); + Comparator<Thing> comp = Comparators.comparing(new ToLongFunction<BasicTest.Thing>() { + @Override + public long applyAsLong(Thing thing) { + return thing.getLongField(); + } + }); + + assertComparisons(things, comp, comparisons); + } + + public void testDoubleComparator() { + Thing[] things = new Thing[doubleValues.length]; + for (int i=0; i<doubleValues.length; i++) + things[i] = new Thing(0, 0L, doubleValues[i], null); + Comparator<Thing> comp = Comparators.comparing(new ToDoubleFunction<BasicTest.Thing>() { + @Override + public double applyAsDouble(Thing thing) { + return thing.getDoubleField(); + } + }); + + assertComparisons(things, comp, comparisons); + } + + public void testComparing() { + Thing[] things = new Thing[doubleValues.length]; + for (int i=0; i<doubleValues.length; i++) + things[i] = new Thing(0, 0L, 0.0, stringValues[i]); + Comparator<Thing> comp = Comparators.comparing(new Function<Thing, String>() { + @Override + public String apply(Thing thing) { + return thing.getStringField(); + } + }); + + assertComparisons(things, comp, comparisons); + } + + public void testNaturalOrderComparator() { + Comparator<String> comp = Comparators.naturalOrder(); + + assertComparisons(stringValues, comp, comparisons); + } + + public void testReverseComparator() { + Comparator<String> cmpr = Comparators.reverseOrder(); + Comparator<String> cmp = cmpr.reverseOrder(); + + assertEquals(cmp.reverseOrder(), cmpr); + assertEquals(0, cmp.compare("a", "a")); + assertEquals(0, cmpr.compare("a", "a")); + assertTrue(cmp.compare("a", "b") < 0); + assertTrue(cmpr.compare("a", "b") > 0); + assertTrue(cmp.compare("b", "a") > 0); + assertTrue(cmpr.compare("b", "a") < 0); + } + + public void testReverseComparator2() { + Comparator<String> cmp = (s1, s2) -> s1.length() - s2.length(); + Comparator<String> cmpr = cmp.reverseOrder(); + + assertEquals(cmpr.reverseOrder(), cmp); + assertEquals(0, cmp.compare("abc", "def")); + assertEquals(0, cmpr.compare("abc", "def")); + assertTrue(cmp.compare("abcd", "def") > 0); + assertTrue(cmpr.compare("abcd", "def") < 0); + assertTrue(cmp.compare("abc", "defg") < 0); + assertTrue(cmpr.compare("abc", "defg") > 0); + } + + @Test(expectedExceptions=NullPointerException.class) + public void testReverseComparatorNPE() { + Comparator<String> cmp = Comparators.reverseOrder(null); + } + + public void testComposeComparator() { + // Longer string in front + Comparator<String> first = (s1, s2) -> s2.length() - s1.length(); + Comparator<String> second = Comparators.naturalOrder(); + Comparator<String> composed = Comparators.compose(first, second); + + assertTrue(composed.compare("abcdefg", "abcdef") < 0); + assertTrue(composed.compare("abcdef", "abcdefg") > 0); + assertTrue(composed.compare("abcdef", "abcdef") == 0); + assertTrue(composed.compare("abcdef", "ghijkl") < 0); + assertTrue(composed.compare("ghijkl", "abcdefg") > 0); + } + + private <K, V> void assertPairComparison(K k1, V v1, K k2, V v2, + Comparator<Map.Entry<K, V>> ck, + Comparator<Map.Entry<K, V>> cv) { + final Map.Entry<K, V> p11 = new AbstractMap.SimpleImmutableEntry<>(k1, v1); + final Map.Entry<K, V> p12 = new AbstractMap.SimpleImmutableEntry<>(k1, v2); + final Map.Entry<K, V> p21 = new AbstractMap.SimpleImmutableEntry<>(k2, v1); + final Map.Entry<K, V> p22 = new AbstractMap.SimpleImmutableEntry<>(k2, v2); + + assertTrue(ck.compare(p11, p11) == 0); + assertTrue(ck.compare(p12, p11) == 0); + assertTrue(ck.compare(p11, p12) == 0); + assertTrue(ck.compare(p12, p22) < 0); + assertTrue(ck.compare(p12, p21) < 0); + assertTrue(ck.compare(p21, p11) > 0); + assertTrue(ck.compare(p21, p12) > 0); + + assertTrue(cv.compare(p11, p11) == 0); + assertTrue(cv.compare(p12, p11) > 0); + assertTrue(cv.compare(p11, p12) < 0); + assertTrue(cv.compare(p12, p22) == 0); + assertTrue(cv.compare(p12, p21) > 0); + assertTrue(cv.compare(p21, p11) == 0); + assertTrue(cv.compare(p21, p12) < 0); + + Comparator<Map.Entry<K, V>> cmp = Comparators.compose(ck, cv); + assertTrue(cmp.compare(p11, p11) == 0); + assertTrue(cmp.compare(p12, p11) > 0); + assertTrue(cmp.compare(p11, p12) < 0); + assertTrue(cmp.compare(p12, p22) < 0); + assertTrue(cmp.compare(p12, p21) < 0); + assertTrue(cmp.compare(p21, p11) > 0); + assertTrue(cmp.compare(p21, p12) > 0); + + cmp = Comparators.compose(cv, ck); + assertTrue(cmp.compare(p11, p11) == 0); + assertTrue(cmp.compare(p12, p11) > 0); + assertTrue(cmp.compare(p11, p12) < 0); + assertTrue(cmp.compare(p12, p22) < 0); + assertTrue(cmp.compare(p12, p21) > 0); + assertTrue(cmp.compare(p21, p11) > 0); + assertTrue(cmp.compare(p21, p12) < 0); + } + + public void testKVComparatorable() { + assertPairComparison(1, "ABC", 2, "XYZ", + Comparators.<Integer, String>naturalOrderKeys(), + Comparators.<Integer, String>naturalOrderValues()); + } + + private static class People { + final String firstName; + final String lastName; + final int age; + + People(String first, String last, int age) { + firstName = first; + lastName = last; + this.age = age; + } + + String getFirstName() { return firstName; } + String getLastName() { return lastName; } + int getAge() { return age; } + long getAgeAsLong() { return (long) age; }; + double getAgeAsDouble() { return (double) age; }; + } + + private final People people[] = { + new People("John", "Doe", 34), + new People("Mary", "Doe", 30), + new People("Maria", "Doe", 14), + new People("Jonah", "Doe", 10), + new People("John", "Cook", 54), + new People("Mary", "Cook", 50), + }; + + public void testKVComparators() { + // Comparator<People> cmp = Comparators.naturalOrder(); // Should fail to compiler as People is not comparable + // We can use simple comparator, but those have been tested above. + // Thus choose to do compose for some level of interation. + Comparator<People> cmp1 = Comparators.comparing((Function<People, String>) People::getFirstName); + Comparator<People> cmp2 = Comparators.comparing((Function<People, String>) People::getLastName); + Comparator<People> cmp = Comparators.compose(cmp1, cmp2); + + assertPairComparison(people[0], people[0], people[1], people[1], + Comparators.<People, People>byKey(cmp), + Comparators.<People, People>byValue(cmp)); + + } + + private <T> void assertComparison(Comparator<T> cmp, T less, T greater) { + assertTrue(cmp.compare(less, greater) < 0, "less"); + assertTrue(cmp.compare(less, less) == 0, "equal"); + assertTrue(cmp.compare(greater, less) > 0, "greater"); + } + + public void testComparatorDefaultMethods() { + Comparator<People> cmp = Comparators.comparing((Function<People, String>) People::getFirstName); + Comparator<People> cmp2 = Comparators.comparing((Function<People, String>) People::getLastName); + // reverseOrder + assertComparison(cmp.reverseOrder(), people[1], people[0]); + // thenComparing(Comparator) + assertComparison(cmp.thenComparing(cmp2), people[0], people[1]); + assertComparison(cmp.thenComparing(cmp2), people[4], people[0]); + // thenComparing(Function) + assertComparison(cmp.thenComparing(People::getLastName), people[0], people[1]); + assertComparison(cmp.thenComparing(People::getLastName), people[4], people[0]); + // thenComparing(ToIntFunction) + assertComparison(cmp.thenComparing(People::getAge), people[0], people[1]); + assertComparison(cmp.thenComparing(People::getAge), people[1], people[5]); + // thenComparing(ToLongFunction) + assertComparison(cmp.thenComparing(People::getAgeAsLong), people[0], people[1]); + assertComparison(cmp.thenComparing(People::getAgeAsLong), people[1], people[5]); + // thenComparing(ToDoubleFunction) + assertComparison(cmp.thenComparing(People::getAgeAsDouble), people[0], people[1]); + assertComparison(cmp.thenComparing(People::getAgeAsDouble), people[1], people[5]); + } + + public void testGreaterOf() { + // lesser + assertSame(Comparators.greaterOf(Comparators.comparing( + (Function<People, String>) People::getFirstName)) + .apply(people[0], people[1]), + people[1]); + // euqal + assertSame(Comparators.greaterOf(Comparators.comparing( + (Function<People, String>) People::getLastName)) + .apply(people[0], people[1]), + people[0]); + // greater + assertSame(Comparators.greaterOf(Comparators.comparing( + (ToIntFunction<People>) People::getAge)) + .apply(people[0], people[1]), + people[0]); + } + + public void testLesserOf() { + // lesser + assertSame(Comparators.lesserOf(Comparators.comparing( + (Function<People, String>) People::getFirstName)) + .apply(people[0], people[1]), + people[0]); + // euqal + assertSame(Comparators.lesserOf(Comparators.comparing( + (Function<People, String>) People::getLastName)) + .apply(people[0], people[1]), + people[0]); + // greater + assertSame(Comparators.lesserOf(Comparators.comparing( + (ToIntFunction<People>) People::getAge)) + .apply(people[0], people[1]), + people[1]); + } + + public void testNulls() { + try { + Comparators.<String>naturalOrder().compare("abc", (String) null); + fail("expected NPE with naturalOrder"); + } catch (NullPointerException npe) {} + try { + Comparators.<String>naturalOrder().compare((String) null, "abc"); + fail("expected NPE with naturalOrder"); + } catch (NullPointerException npe) {} + + try { + Comparators.<String>reverseOrder().compare("abc", (String) null); + fail("expected NPE with naturalOrder"); + } catch (NullPointerException npe) {} + try { + Comparators.<String>reverseOrder().compare((String) null, "abc"); + fail("expected NPE with naturalOrder"); + } catch (NullPointerException npe) {} + + try { + Comparator<Map.Entry<String, String>> cmp = Comparators.byKey(null); + fail("byKey(null) should throw NPE"); + } catch (NullPointerException npe) {} + + try { + Comparator<Map.Entry<String, String>> cmp = Comparators.byValue(null); + fail("byValue(null) should throw NPE"); + } catch (NullPointerException npe) {} + + try { + Comparator<People> cmp = Comparators.comparing((Function<People, String>) null); + fail("comparing(null) should throw NPE"); + } catch (NullPointerException npe) {} + try { + Comparator<People> cmp = Comparators.comparing((ToIntFunction<People>) null); + fail("comparing(null) should throw NPE"); + } catch (NullPointerException npe) {} + try { + Comparator<People> cmp = Comparators.comparing((ToLongFunction<People>) null); + fail("comparing(null) should throw NPE"); + } catch (NullPointerException npe) {} + try { + Comparator<People> cmp = Comparators.comparing((ToDoubleFunction<People>) null); + fail("comparing(null) should throw NPE"); + } catch (NullPointerException npe) {} + + try { + BinaryOperator<String> op = Comparators.lesserOf(null); + fail("lesserOf(null) should throw NPE"); + } catch (NullPointerException npe) {} + + try { + BinaryOperator<String> op = Comparators.greaterOf(null); + fail("lesserOf(null) should throw NPE"); + } catch (NullPointerException npe) {} + } +}
--- a/test/java/util/ComparatorsTest.java Fri Apr 12 12:12:53 2013 -0700 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,353 +0,0 @@ -/* - * Copyright (c) 2012, 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 8001667 - * @run testng ComparatorsTest - */ - -import java.util.Comparator; -import java.util.Comparators; -import java.util.AbstractMap; -import java.util.Map; -import org.testng.annotations.Test; - -import java.util.function.Function; -import java.util.function.ToIntFunction; -import java.util.function.ToLongFunction; -import java.util.function.ToDoubleFunction; - -import static org.testng.Assert.assertEquals; -import static org.testng.Assert.assertTrue; -import static org.testng.Assert.assertSame; - -/** - * Unit tests for helper methods in Comparators - */ -@Test(groups = "unit") -public class ComparatorsTest { - private static class Thing { - public final int intField; - public final long longField; - public final double doubleField; - public final String stringField; - - private Thing(int intField, long longField, double doubleField, String stringField) { - this.intField = intField; - this.longField = longField; - this.doubleField = doubleField; - this.stringField = stringField; - } - - public int getIntField() { - return intField; - } - - public long getLongField() { - return longField; - } - - public double getDoubleField() { - return doubleField; - } - - public String getStringField() { - return stringField; - } - } - - private final int[] intValues = { -2, -2, -1, -1, 0, 0, 1, 1, 2, 2 }; - private final long[] longValues = { -2, -2, -1, -1, 0, 0, 1, 1, 2, 2 }; - private final double[] doubleValues = { -2, -2, -1, -1, 0, 0, 1, 1, 2, 2 }; - private final String[] stringValues = { "a", "a", "b", "b", "c", "c", "d", "d", "e", "e" }; - private final int[] comparisons = { 0, -1, 0, -1, 0, -1, 0, -1, 0 }; - - private<T> void assertComparisons(T[] things, Comparator<T> comp, int[] comparisons) { - for (int i=0; i<comparisons.length; i++) { - assertEquals(comparisons.length + 1, things.length); - assertEquals(comparisons[i], comp.compare(things[i], things[i+1])); - assertEquals(-comparisons[i], comp.compare(things[i+1], things[i])); - } - } - - public void testIntComparator() { - Thing[] things = new Thing[intValues.length]; - for (int i=0; i<intValues.length; i++) - things[i] = new Thing(intValues[i], 0L, 0.0, null); - Comparator<Thing> comp = Comparators.comparing(new ToIntFunction<ComparatorsTest.Thing>() { - @Override - public int applyAsInt(Thing thing) { - return thing.getIntField(); - } - }); - - assertComparisons(things, comp, comparisons); - } - - public void testLongComparator() { - Thing[] things = new Thing[longValues.length]; - for (int i=0; i<longValues.length; i++) - things[i] = new Thing(0, longValues[i], 0.0, null); - Comparator<Thing> comp = Comparators.comparing(new ToLongFunction<ComparatorsTest.Thing>() { - @Override - public long applyAsLong(Thing thing) { - return thing.getLongField(); - } - }); - - assertComparisons(things, comp, comparisons); - } - - public void testDoubleComparator() { - Thing[] things = new Thing[doubleValues.length]; - for (int i=0; i<doubleValues.length; i++) - things[i] = new Thing(0, 0L, doubleValues[i], null); - Comparator<Thing> comp = Comparators.comparing(new ToDoubleFunction<ComparatorsTest.Thing>() { - @Override - public double applyAsDouble(Thing thing) { - return thing.getDoubleField(); - } - }); - - assertComparisons(things, comp, comparisons); - } - - public void testComparing() { - Thing[] things = new Thing[doubleValues.length]; - for (int i=0; i<doubleValues.length; i++) - things[i] = new Thing(0, 0L, 0.0, stringValues[i]); - Comparator<Thing> comp = Comparators.comparing(new Function<Thing, String>() { - @Override - public String apply(Thing thing) { - return thing.getStringField(); - } - }); - - assertComparisons(things, comp, comparisons); - } - - public void testNaturalOrderComparator() { - Comparator<String> comp = Comparators.naturalOrder(); - - assertComparisons(stringValues, comp, comparisons); - } - - public void testReverseComparator() { - Comparator<String> cmpr = Comparators.reverseOrder(); - Comparator<String> cmp = cmpr.reverseOrder(); - - assertEquals(cmp.reverseOrder(), cmpr); - assertEquals(0, cmp.compare("a", "a")); - assertEquals(0, cmpr.compare("a", "a")); - assertTrue(cmp.compare("a", "b") < 0); - assertTrue(cmpr.compare("a", "b") > 0); - assertTrue(cmp.compare("b", "a") > 0); - assertTrue(cmpr.compare("b", "a") < 0); - } - - public void testReverseComparator2() { - Comparator<String> cmp = (s1, s2) -> s1.length() - s2.length(); - Comparator<String> cmpr = cmp.reverseOrder(); - - assertEquals(cmpr.reverseOrder(), cmp); - assertEquals(0, cmp.compare("abc", "def")); - assertEquals(0, cmpr.compare("abc", "def")); - assertTrue(cmp.compare("abcd", "def") > 0); - assertTrue(cmpr.compare("abcd", "def") < 0); - assertTrue(cmp.compare("abc", "defg") < 0); - assertTrue(cmpr.compare("abc", "defg") > 0); - } - - @Test(expectedExceptions=NullPointerException.class) - public void testReverseComparatorNPE() { - Comparator<String> cmp = Comparators.reverseOrder(null); - } - - public void testComposeComparator() { - // Longer string in front - Comparator<String> first = (s1, s2) -> s2.length() - s1.length(); - Comparator<String> second = Comparators.naturalOrder(); - Comparator<String> composed = Comparators.compose(first, second); - - assertTrue(composed.compare("abcdefg", "abcdef") < 0); - assertTrue(composed.compare("abcdef", "abcdefg") > 0); - assertTrue(composed.compare("abcdef", "abcdef") == 0); - assertTrue(composed.compare("abcdef", "ghijkl") < 0); - assertTrue(composed.compare("ghijkl", "abcdefg") > 0); - } - - private <K, V> void assertPairComparison(K k1, V v1, K k2, V v2, - Comparator<Map.Entry<K, V>> ck, - Comparator<Map.Entry<K, V>> cv) { - final Map.Entry<K, V> p11 = new AbstractMap.SimpleImmutableEntry<>(k1, v1); - final Map.Entry<K, V> p12 = new AbstractMap.SimpleImmutableEntry<>(k1, v2); - final Map.Entry<K, V> p21 = new AbstractMap.SimpleImmutableEntry<>(k2, v1); - final Map.Entry<K, V> p22 = new AbstractMap.SimpleImmutableEntry<>(k2, v2); - - assertTrue(ck.compare(p11, p11) == 0); - assertTrue(ck.compare(p12, p11) == 0); - assertTrue(ck.compare(p11, p12) == 0); - assertTrue(ck.compare(p12, p22) < 0); - assertTrue(ck.compare(p12, p21) < 0); - assertTrue(ck.compare(p21, p11) > 0); - assertTrue(ck.compare(p21, p12) > 0); - - assertTrue(cv.compare(p11, p11) == 0); - assertTrue(cv.compare(p12, p11) > 0); - assertTrue(cv.compare(p11, p12) < 0); - assertTrue(cv.compare(p12, p22) == 0); - assertTrue(cv.compare(p12, p21) > 0); - assertTrue(cv.compare(p21, p11) == 0); - assertTrue(cv.compare(p21, p12) < 0); - - Comparator<Map.Entry<K, V>> cmp = Comparators.compose(ck, cv); - assertTrue(cmp.compare(p11, p11) == 0); - assertTrue(cmp.compare(p12, p11) > 0); - assertTrue(cmp.compare(p11, p12) < 0); - assertTrue(cmp.compare(p12, p22) < 0); - assertTrue(cmp.compare(p12, p21) < 0); - assertTrue(cmp.compare(p21, p11) > 0); - assertTrue(cmp.compare(p21, p12) > 0); - - cmp = Comparators.compose(cv, ck); - assertTrue(cmp.compare(p11, p11) == 0); - assertTrue(cmp.compare(p12, p11) > 0); - assertTrue(cmp.compare(p11, p12) < 0); - assertTrue(cmp.compare(p12, p22) < 0); - assertTrue(cmp.compare(p12, p21) > 0); - assertTrue(cmp.compare(p21, p11) > 0); - assertTrue(cmp.compare(p21, p12) < 0); - } - - public void testKVComparatorable() { - assertPairComparison(1, "ABC", 2, "XYZ", - Comparators.<Integer, String>naturalOrderKeys(), - Comparators.<Integer, String>naturalOrderValues()); - } - - private static class People { - final String firstName; - final String lastName; - final int age; - - People(String first, String last, int age) { - firstName = first; - lastName = last; - this.age = age; - } - - String getFirstName() { return firstName; } - String getLastName() { return lastName; } - int getAge() { return age; } - long getAgeAsLong() { return (long) age; }; - double getAgeAsDouble() { return (double) age; }; - } - - private final People people[] = { - new People("John", "Doe", 34), - new People("Mary", "Doe", 30), - new People("Maria", "Doe", 14), - new People("Jonah", "Doe", 10), - new People("John", "Cook", 54), - new People("Mary", "Cook", 50), - }; - - public void testKVComparators() { - // Comparator<People> cmp = Comparators.naturalOrder(); // Should fail to compiler as People is not comparable - // We can use simple comparator, but those have been tested above. - // Thus choose to do compose for some level of interation. - Comparator<People> cmp1 = Comparators.comparing((Function<People, String>) People::getFirstName); - Comparator<People> cmp2 = Comparators.comparing((Function<People, String>) People::getLastName); - Comparator<People> cmp = Comparators.compose(cmp1, cmp2); - - assertPairComparison(people[0], people[0], people[1], people[1], - Comparators.<People, People>byKey(cmp), - Comparators.<People, People>byValue(cmp)); - - } - - private <T> void assertComparison(Comparator<T> cmp, T less, T greater) { - assertTrue(cmp.compare(less, greater) < 0, "less"); - assertTrue(cmp.compare(less, less) == 0, "equal"); - assertTrue(cmp.compare(greater, less) > 0, "greater"); - } - - public void testComparatorDefaultMethods() { - Comparator<People> cmp = Comparators.comparing((Function<People, String>) People::getFirstName); - Comparator<People> cmp2 = Comparators.comparing((Function<People, String>) People::getLastName); - // reverseOrder - assertComparison(cmp.reverseOrder(), people[1], people[0]); - // thenComparing(Comparator) - assertComparison(cmp.thenComparing(cmp2), people[0], people[1]); - assertComparison(cmp.thenComparing(cmp2), people[4], people[0]); - // thenComparing(Function) - assertComparison(cmp.thenComparing(People::getLastName), people[0], people[1]); - assertComparison(cmp.thenComparing(People::getLastName), people[4], people[0]); - // thenComparing(ToIntFunction) - assertComparison(cmp.thenComparing(People::getAge), people[0], people[1]); - assertComparison(cmp.thenComparing(People::getAge), people[1], people[5]); - // thenComparing(ToLongFunction) - assertComparison(cmp.thenComparing(People::getAgeAsLong), people[0], people[1]); - assertComparison(cmp.thenComparing(People::getAgeAsLong), people[1], people[5]); - // thenComparing(ToDoubleFunction) - assertComparison(cmp.thenComparing(People::getAgeAsDouble), people[0], people[1]); - assertComparison(cmp.thenComparing(People::getAgeAsDouble), people[1], people[5]); - } - - public void testGreaterOf() { - // lesser - assertSame(Comparators.greaterOf(Comparators.comparing( - (Function<People, String>) People::getFirstName)) - .apply(people[0], people[1]), - people[1]); - // euqal - assertSame(Comparators.greaterOf(Comparators.comparing( - (Function<People, String>) People::getLastName)) - .apply(people[0], people[1]), - people[0]); - // greater - assertSame(Comparators.greaterOf(Comparators.comparing( - (ToIntFunction<People>) People::getAge)) - .apply(people[0], people[1]), - people[0]); - } - - public void testLesserOf() { - // lesser - assertSame(Comparators.lesserOf(Comparators.comparing( - (Function<People, String>) People::getFirstName)) - .apply(people[0], people[1]), - people[0]); - // euqal - assertSame(Comparators.lesserOf(Comparators.comparing( - (Function<People, String>) People::getLastName)) - .apply(people[0], people[1]), - people[0]); - // greater - assertSame(Comparators.lesserOf(Comparators.comparing( - (ToIntFunction<People>) People::getAge)) - .apply(people[0], people[1]), - people[1]); - } -} \ No newline at end of file