added after review

core-java-modules/core-java-string-operations-3/src/main/java/com/baeldung/tostring/StringCastUtils.java

@@ -2,9 +2,14 @@ package com.baeldung.tostring;
 
 public class StringCastUtils {
     public static String castToString(Object object) {
-        if (object instanceof String) {
+        if (object instanceof String)
             return (String) object;
-        }
+        return null;
+    }
+
+    public static String getToString(Object object) {
+        if (object != null)
+            return object.toString();
         return null;
     }
 }

core-java-modules/core-java-string-operations-3/src/test/java/com/baeldung/tostring/ToStringUnitTest.java

@@ -89,4 +89,14 @@ public class ToStringUnitTest {
 
         assertEquals(null, StringCastUtils.castToString(obj));
     }
+
+    @Test
+    public void givenIntegerNotNull_whenCastToObject_thenGetToStringReturnsString() {
+        Integer input = 1234;
+
+        Object obj = input;
+
+        assertEquals("1234", StringCastUtils.getToString(obj));
+        assertNotSame("1234", StringCastUtils.getToString(obj));
+    }
 }