Merge branch '__rultor'

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}
+ *
+ * <p>There is no thread-safety guarantee.
+ *
+ * @author Vedran Vatavuk (123vgv@gmail.com)
+ * @version $Id$
+ * @param <T> Type of input
+ * @since 0.31
+ */
+public final class Equality<T extends Bytes> implements Scalar<Integer> {
+
+    /**
+     * 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();
+    }
+}

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();
+        }
+    }
+}