[ODTN] Support of multiple optical bands (L, C, and S band).
- patch 1: first commit
- patch 2: example driver, checkstyle
- patch 3,4,5: checkstyle
- patch 6,7: andrea's comments

Change-Id: I1f872e5df76073f427da8184c4f2a4e18dfbf4bb
diff --git a/core/api/src/main/java/org/onosproject/net/OpticalBandType.java b/core/api/src/main/java/org/onosproject/net/OpticalBandType.java
new file mode 100644
index 0000000..06b5b4f
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/OpticalBandType.java
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2023-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * This Work is contributed by CNR within the B5G-OPEN project.
+ */
+
+package org.onosproject.net;
+
+
+/**
+ * Represents type of optical bands.
+ *
+ */
+public enum OpticalBandType {
+    L_BAND, // Starts at 184500 GHz ends at 191500 GHz
+    C_BAND, // Starts at 191500 GHz ends at 195500 GHz
+    S_BAND; // Starts at 195500 GHz ends at 205300 GHz
+}
+