Fix: SpotBugs violation and improve test for ElGamalEncryption

Author: Shewale41

src/main/java/com/thealgorithms/ciphers/ElGamalEncryption.java

@@ -16,7 +16,6 @@ public final class ElGamalEncryption {
 
     private static final SecureRandom RANDOM = new SecureRandom();
 
-    // Private constructor to prevent instantiation
     private ElGamalEncryption() {
         throw new UnsupportedOperationException("Utility class");
     }
@@ -27,25 +26,21 @@ private ElGamalEncryption() {
      * @param message the plaintext message to encrypt
      * @param bitLength the bit length for prime generation
      */
-    @SuppressWarnings({"PMD.SystemPrintln", "PMD.DataflowAnomalyAnalysis"})
+    @SuppressWarnings({ "PMD.SystemPrintln", "PMD.DataflowAnomalyAnalysis" })
     public static void runElGamal(final String message, final int bitLength) {
-        // Key generation
         final BigInteger p = BigInteger.probablePrime(bitLength, RANDOM);
         final BigInteger g = new BigInteger("2");
         final BigInteger x = new BigInteger(bitLength - 2, RANDOM);
         final BigInteger y = g.modPow(x, p);
 
-        // Encryption
         final BigInteger k = new BigInteger(bitLength - 2, RANDOM);
         final BigInteger a = g.modPow(k, p);
         final BigInteger m = new BigInteger(message.getBytes());
         final BigInteger b = (y.modPow(k, p).multiply(m)).mod(p);
 
-        // Decryption
         final BigInteger aInverse = a.modPow(p.subtract(BigInteger.ONE).subtract(x), p);
         final BigInteger decrypted = (b.multiply(aInverse)).mod(p);
 
-        // Display results
         System.out.println("Prime (p): " + p);
         System.out.println("Generator (g): " + g);
         System.out.println("Private Key (x): " + x);

src/test/java/com/thealgorithms/ciphers/ElGamalEncryptionTest.java

@@ -1,8 +1,9 @@
 package com.thealgorithms.ciphers;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-
 import org.junit.jupiter.api.Test;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Modifier;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * Unit tests for {@link ElGamalEncryption}.
@@ -11,8 +12,6 @@ public class ElGamalEncryptionTest {
 
     @Test
     void testEncryptionDecryption() {
-        // Basic functional test (simulated output check)
-        // Since ElGamal uses randomization, we only verify successful execution
         try {
             ElGamalEncryption.runElGamal("Hello", 64);
         } catch (Exception e) {
@@ -21,14 +20,9 @@ void testEncryptionDecryption() {
     }
 
     @Test
-    void testUtilityConstructor() {
-        // Ensures the utility class constructor is private
-        try {
-            var constructor = ElGamalEncryption.class.getDeclaredConstructor();
-            constructor.setAccessible(true);
-            constructor.newInstance();
-        } catch (Exception e) {
-            assertEquals("Utility class", e.getCause().getMessage());
-        }
+    void testUtilityConstructor() throws NoSuchMethodException {
+        Constructor<ElGamalEncryption> constructor = ElGamalEncryption.class.getDeclaredConstructor();
+        assertTrue(Modifier.isPrivate(constructor.getModifiers()),
+                "Utility class constructor should be private");
     }
 }