diff --git a/src/main/java/org/cactoos/scalar/Equality.java b/src/main/java/org/cactoos/scalar/Equality.java new file mode 100644 index 0000000000..75eb39d42a --- /dev/null +++ b/src/main/java/org/cactoos/scalar/Equality.java @@ -0,0 +1,85 @@ +/** + * The MIT License (MIT) + * + * Copyright (c) 2017-2018 Yegor Bugayenko + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ +package org.cactoos.scalar; + +import org.cactoos.Bytes; +import org.cactoos.Scalar; + +/** + * Equality. + * + * Returns: + * the value {@code 0} if {@code x == y}; + * the value {@code -1} if {@code x < y}; + * the value {@code 1} if {@code x > y} + * + *

There is no thread-safety guarantee. + * + * @author Vedran Vatavuk (123vgv@gmail.com) + * @version $Id$ + * @param Type of input + * @since 0.31 + */ +public final class Equality implements Scalar { + + /** + * Left. + */ + private final T left; + + /** + * Right. + */ + private final T right; + + /** + * Ctor. + * @param lft Left + * @param rght Right + */ + public Equality(final T lft, final T rght) { + this.left = lft; + this.right = rght; + } + + @Override + public Integer value() throws Exception { + final byte[] lft = this.left.asBytes(); + final byte[] rght = this.right.asBytes(); + return new Ternary<>( + () -> lft.length == rght.length, + () -> { + int result = 0; + for (int idx = rght.length - 1; idx >= 0; --idx) { + result = lft[idx] - rght[idx]; + if (result != 0) { + break; + } + } + return Integer.signum(result); + }, + () -> Integer.signum(lft.length - rght.length) + ).value(); + } +} diff --git a/src/test/java/org/cactoos/scalar/EqualityTest.java b/src/test/java/org/cactoos/scalar/EqualityTest.java new file mode 100644 index 0000000000..5e905ca474 --- /dev/null +++ b/src/test/java/org/cactoos/scalar/EqualityTest.java @@ -0,0 +1,124 @@ +/** + * The MIT License (MIT) + * + * Copyright (c) 2017-2018 Yegor Bugayenko + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ +package org.cactoos.scalar; + +import org.cactoos.Bytes; +import org.cactoos.matchers.ScalarHasValue; +import org.hamcrest.MatcherAssert; +import org.junit.Test; + +/** + * Test case for {@link Equality}. + * @author Vedran Vatavuk (123vgv@gmail.com) + * @version $Id$ + * @since 0.31 + * @checkstyle JavadocMethodCheck (500 lines) + * @checkstyle MagicNumberCheck (500 lines) + */ +public final class EqualityTest { + + @Test + public void notEqualLeft() throws Exception { + MatcherAssert.assertThat( + new Equality<>( + new EqualityTest.Letters("A"), new EqualityTest.Letters("AB") + ), + new ScalarHasValue<>(-1) + ); + } + + @Test + public void notEqualRight() throws Exception { + MatcherAssert.assertThat( + new Equality<>( + new EqualityTest.Letters("AB"), new EqualityTest.Letters("A") + ), + new ScalarHasValue<>(1) + ); + } + + @Test + public void notEqualLeftWithSameSize() throws Exception { + MatcherAssert.assertThat( + new Equality<>( + new EqualityTest.Letters("A"), new EqualityTest.Letters("B") + ), + new ScalarHasValue<>(-1) + ); + } + + @Test + public void notEqualRightWithSameSize() throws Exception { + MatcherAssert.assertThat( + new Equality<>( + new EqualityTest.Letters("B"), new EqualityTest.Letters("A") + ), + new ScalarHasValue<>(1) + ); + } + + @Test + public void equal() throws Exception { + MatcherAssert.assertThat( + new Equality<>( + new EqualityTest.Letters("A"), new EqualityTest.Letters("A") + ), + new ScalarHasValue<>(0) + ); + } + + @Test + public void compareEmptyArrays() throws Exception { + MatcherAssert.assertThat( + new Equality<>( + new EqualityTest.Letters(""), new EqualityTest.Letters("") + ), + new ScalarHasValue<>(0) + ); + } + + /** + * Weight. + */ + private static final class Letters implements Bytes { + + /** + * Bytes. + */ + private final String text; + + /** + * Ctor. + * @param txt Text + */ + Letters(final String txt) { + this.text = txt; + } + + @Override + public byte[] asBytes() { + return this.text.getBytes(); + } + } +}