update some utils methods and add new one

Author: JavaSaBr

rlib-common/src/main/java/com/ss/rlib/common/util/ArrayUtils.java

@@ -1890,7 +1890,7 @@ public static boolean isEmpty(@Nullable double[] array) {
     }
 
     /**
-     * Create a new array with mapped each element from source array.
+     * Convert T array to R array if a source array is not null.
      *
      * @param <T>        the source component type.
      * @param <M>        the mapped element's type.
@@ -1922,6 +1922,28 @@ public static boolean isEmpty(@Nullable double[] array) {
         return resultArray;
     }
 
+    /**
+     * Convert long array to int array.
+     *
+     * @param source the source array.
+     * @return the int array.
+     * @since 9.3.0
+     */
+    public static int @NotNull [] longsToInts(long @NotNull [] source) {
+
+        if (source.length == 0) {
+            return ArrayUtils.EMPTY_INT_ARRAY;
+        }
+
+        int[] resultArray = new int[source.length];
+
+        for (int i = 0; i < source.length; i++) {
+            resultArray[i] = (int) source[i];
+        }
+
+        return resultArray;
+    }
+
     private ArrayUtils() {
         throw new RuntimeException();
     }

rlib-common/src/test/java/com/ss/rlib/common/test/util/ArrayUtilsTests.java

@@ -67,4 +67,18 @@ void mapNullableTest() {
             ArrayFactory.toArray(8, 1, 6), ArrayUtils.mapNullable(strings, Integer::parseInt, Integer.class)
         );
     }
+
+    @Test
+    void longsToIntsTest() {
+
+        Assertions.assertArrayEquals(
+            ArrayFactory.toIntArray(1, 5, 3),
+            ArrayUtils.longsToInts(ArrayFactory.toLongArray(1, 5, 3))
+        );
+
+        Assertions.assertArrayEquals(
+            ArrayUtils.EMPTY_INT_ARRAY,
+            ArrayUtils.longsToInts(ArrayUtils.EMPTY_LONG_ARRAY)
+        );
+    }
 }