iluwatar#105 Updated Random Number generation code and its unit test

Shanty97 · Feb 11, 2024 · 826733f · 826733f
1 parent f3a57cc
commit 826733f
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Showing 2 changed files with 30 additions and 13 deletions.
diff --git a/src/main/java/math/RandomNumber.java b/src/main/java/math/RandomNumber.java
@@ -42,18 +42,24 @@ public class RandomNumber {
 	 * 
 	 */
 	public static <T extends Number> Number getRandomNumber(T start, T end) {
-
-		if ((start instanceof Byte && end instanceof Byte) || 
-				(start instanceof Short && end instanceof Short) || 
-				(start instanceof Integer && end instanceof Integer))
-			return (int) start.intValue() + new Random().nextInt(end.intValue() - start.intValue() + 1);
-		else if (start instanceof Long && end instanceof Long)
-			return (long) start.longValue() + new Random().nextLong(end.longValue() - start.longValue() + 1);
-		else if (start instanceof Float && end instanceof Float)
-			return (float) start.floatValue() + new Random().nextFloat(end.floatValue() - start.floatValue() + 1);
-		else if (start instanceof Double && end instanceof Double)
-			return (double) start.doubleValue() + new Random().nextDouble(end.doubleValue() - start.doubleValue() + 1);
-		return end;
+
+		Random random = new Random();
+
+		if ((start instanceof Byte && end instanceof Byte)) {
+			return (byte) (start.byteValue() + random.nextInt(end.byteValue() - start.byteValue() + 1));
+		} else if ((start instanceof Byte && end instanceof Byte) || (start instanceof Short && end instanceof Short)) {
+			return (short) (start.shortValue() + random.nextInt(end.shortValue() - start.shortValue() + 1));
+		} else if ((start instanceof Integer && end instanceof Integer)) {
+			return (int) (start.intValue() + random.nextInt(end.intValue() - start.intValue() + 1));
+		} else if (start instanceof Long && end instanceof Long) {
+			return (long) (start.longValue() + random.nextLong(end.longValue() - start.longValue() + 1));
+		} else if (start instanceof Float && end instanceof Float) {
+			return (float) (start.floatValue() + random.nextFloat(end.floatValue() - start.floatValue() + 1));
+		} else if (start instanceof Double && end instanceof Double) {
+			return (double) (start.doubleValue() + random.nextDouble(end.doubleValue() - start.doubleValue() + 1));
+		} else {
+			throw new IllegalArgumentException("Invalid Numbers As Arguments "+start.getClass()+" and "+end.getClass());
+		}
 
 	}
 

diff --git a/src/test/java/math/RandomNumberTest.java b/src/test/java/math/RandomNumberTest.java
@@ -25,6 +25,8 @@
 package math;
 
 import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 
 
 import org.junit.jupiter.api.Test;
@@ -64,7 +66,7 @@ void test_longRandomNumber() {
 		// Test for Long range
 		Number longResult = RandomNumber.getRandomNumber(Long.valueOf((long) -100), Long.valueOf((long) 2500));
 		assertTrue(longResult instanceof Long);
-		assertTrue((longResult.longValue() <= -100) && (longResult.longValue() <= 2500));
+		assertTrue((longResult.longValue() >= -100) && (longResult.longValue() <= 2500));
 	}
 
 	/**
@@ -88,4 +90,13 @@ void test_doubleRandomNumber() {
 		assertTrue(doubleResult instanceof Double);
 		assertTrue((doubleResult.doubleValue() >= 100.12) && (doubleResult.doubleValue() <= 200.28));
 	}
+
+	/**
+	 * Test for invalid argument numbers
+	 */
+	@Test
+	void test_invalidNumberArguments() {
+		// Test for Double range
+		assertThrows(IllegalArgumentException.class, () -> RandomNumber.getRandomNumber(Double.valueOf((double) 100.12), Integer.valueOf((int) 200)));
+	}
 }