Added isogram utility class and unit tests (#6594)

* added isogram utility class and unit tests Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * checking lint issue Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * checking lint issue Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * checking lint issue Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * checking lint issue Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * checking lint issue Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * checking lint issue Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * checking lint issue Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * checking lint issue Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * linter fix Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * fix: HideUtilityClassConstructor Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * linter fix Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * updated isogram class to final Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * pipeline bug fixing Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> * renamed function names and few fixes w.r.t to suggestion Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com> --------- Signed-off-by: JeevaRamanathan <jeevaramanathan.m@infosys.com>
2025-12-19 07:00:35 +08:00 · 2025-10-03 17:03:12 +05:30
parent 8d14b492fd
commit 7e29be3ad8
2 changed files with 209 additions and 0 deletions
--- a/src/test/java/com/thealgorithms/strings/IsogramTest.java
+++ b/src/test/java/com/thealgorithms/strings/IsogramTest.java
@@ -0,0 +1,117 @@
+package com.thealgorithms.strings;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.stream.Stream;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+
+public class IsogramTest {
+
+    record IsogramTestCase(String input, boolean expected) {
+    }
+
+    private static Stream<IsogramTestCase> isAlphabeticIsogram() {
+        return Stream.of(
+            // Valid isograms (only checks letters)
+            new IsogramTestCase("uncopyrightable", true), new IsogramTestCase("dermatoglyphics", true), new IsogramTestCase("background", true), new IsogramTestCase("python", true), new IsogramTestCase("keyboard", true), new IsogramTestCase("clipboard", true), new IsogramTestCase("flowchart", true),
+            new IsogramTestCase("bankruptcy", true), new IsogramTestCase("computer", true), new IsogramTestCase("algorithms", true),
+
+            // Not isograms - letters repeat
+            new IsogramTestCase("hello", false), new IsogramTestCase("programming", false), new IsogramTestCase("java", false), new IsogramTestCase("coffee", false), new IsogramTestCase("book", false), new IsogramTestCase("letter", false), new IsogramTestCase("mississippi", false),
+            new IsogramTestCase("google", false),
+
+            // Edge cases
+            new IsogramTestCase("", true), new IsogramTestCase("a", true), new IsogramTestCase("ab", true), new IsogramTestCase("abc", true), new IsogramTestCase("aa", false), new IsogramTestCase("abcdefghijklmnopqrstuvwxyz", true),
+
+            // Case insensitive
+            new IsogramTestCase("Python", true), new IsogramTestCase("BACKGROUND", true), new IsogramTestCase("Hello", false), new IsogramTestCase("PROGRAMMING", false));
+    }
+
+    private static Stream<IsogramTestCase> isFullIsogram() {
+        return Stream.of(
+            // Valid isograms (checks all characters)
+            new IsogramTestCase("uncopyrightable", true), new IsogramTestCase("dermatoglyphics", true), new IsogramTestCase("background", true), new IsogramTestCase("python", true), new IsogramTestCase("keyboard", true), new IsogramTestCase("clipboard", true), new IsogramTestCase("flowchart", true),
+            new IsogramTestCase("bankruptcy", true), new IsogramTestCase("computer", true), new IsogramTestCase("algorithms", true),
+
+            // Not isograms - characters repeat
+            new IsogramTestCase("hello", false), new IsogramTestCase("programming", false), new IsogramTestCase("java", false), new IsogramTestCase("coffee", false), new IsogramTestCase("book", false), new IsogramTestCase("letter", false), new IsogramTestCase("mississippi", false),
+            new IsogramTestCase("google", false),
+
+            // Edge cases
+            new IsogramTestCase("", true), new IsogramTestCase("a", true), new IsogramTestCase("ab", true), new IsogramTestCase("abc", true), new IsogramTestCase("aa", false), new IsogramTestCase("abcdefghijklmnopqrstuvwxyz", true),
+
+            // Case insensitive
+            new IsogramTestCase("Python", true), new IsogramTestCase("BACKGROUND", true), new IsogramTestCase("Hello", false), new IsogramTestCase("PROGRAMMING", false),
+
+            // Strings with symbols and numbers
+            new IsogramTestCase("abc@def", true), // all characters unique
+            new IsogramTestCase("test-case", false), // 't', 's', 'e' repeat
+            new IsogramTestCase("python123", true), // all characters unique
+            new IsogramTestCase("hello@123", false), // 'l' repeats
+            new IsogramTestCase("abc123!@#", true), // all characters unique
+            new IsogramTestCase("test123test", false), // 't', 'e', 's' repeat
+            new IsogramTestCase("1234567890", true), // all digits unique
+            new IsogramTestCase("12321", false), // '1' and '2' repeat
+            new IsogramTestCase("!@#$%^&*()", true) // all special characters unique
+        );
+    }
+
+    @ParameterizedTest
+    @MethodSource("isAlphabeticIsogram")
+    void testIsogramByArray(IsogramTestCase testCase) {
+        assertEquals(testCase.expected(), Isogram.isAlphabeticIsogram(testCase.input()));
+    }
+
+    @ParameterizedTest
+    @MethodSource("isFullIsogram")
+    void testIsogramByLength(IsogramTestCase testCase) {
+        assertEquals(testCase.expected(), Isogram.isFullIsogram(testCase.input()));
+    }
+
+    @Test
+    void testNullInputByArray() {
+        assertTrue(Isogram.isAlphabeticIsogram(null));
+    }
+
+    @Test
+    void testNullInputByLength() {
+        assertTrue(Isogram.isFullIsogram(null));
+    }
+
+    @Test
+    void testEmptyStringByArray() {
+        assertTrue(Isogram.isAlphabeticIsogram(""));
+    }
+
+    @Test
+    void testEmptyStringByLength() {
+        assertTrue(Isogram.isFullIsogram(""));
+    }
+
+    @Test
+    void testAlphabeticIsogramThrowsException() {
+        // Test that IllegalArgumentException is thrown for non-alphabetic characters
+        assertThrows(IllegalArgumentException.class, () -> Isogram.isAlphabeticIsogram("1"));
+        assertThrows(IllegalArgumentException.class, () -> Isogram.isAlphabeticIsogram("@"));
+        assertThrows(IllegalArgumentException.class, () -> Isogram.isAlphabeticIsogram("python!"));
+        assertThrows(IllegalArgumentException.class, () -> Isogram.isAlphabeticIsogram("123algorithm"));
+        assertThrows(IllegalArgumentException.class, () -> Isogram.isAlphabeticIsogram("hello123"));
+        assertThrows(IllegalArgumentException.class, () -> Isogram.isAlphabeticIsogram("!@@#$%^&*()"));
+    }
+
+    @Test
+    void testFullIsogramWithMixedCharacters() {
+        // Test that full isogram method handles all character types without exceptions
+        assertTrue(Isogram.isFullIsogram("abc123"));
+        assertFalse(Isogram.isFullIsogram("test@email")); // 'e' repeats
+        assertFalse(Isogram.isFullIsogram("hello123")); // 'l' repeats
+        assertTrue(Isogram.isFullIsogram("1234567890"));
+        assertFalse(Isogram.isFullIsogram("12321")); // '1' and '2' repeat
+        assertTrue(Isogram.isFullIsogram("!@#$%^&*()"));
+    }
+}