[int-to-short] add intToShort()

Author: sk1418

core-java-modules/core-java-numbers-conversions-2/src/test/java/com/baeldung/inttoshort/ConvertIntToShortUnitTest.java

@@ -1,6 +1,7 @@
 package com.baeldung.inttoshort;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import org.junit.jupiter.api.Test;
 
@@ -33,4 +34,22 @@ void whenIntOutOfShortRange_thenGetTheUnexpectedResult() {
         assertEquals(-31616, result);
     }
 
+    short intToShort(int i) {
+        if (i < Short.MIN_VALUE || i > Short.MAX_VALUE) {
+            throw new IllegalArgumentException("Int is out of short range");
+        }
+        return (short) i;
+    }
+
+    @Test
+    void whenCheckShortRangeBeforeCasting_thenGetExpectedResult() {
+        short expected = 42;
+        int int42 = 42;
+        assertEquals(expected, intToShort(int42));
+
+        int oneMillion = 1_000_000;
+        assertThrows(IllegalArgumentException.class, () -> intToShort(oneMillion));
+
+    }
+
 }