ONOS-4417 Remove OtuPort out of core.

Change-Id: Ibc72ee617b238005585f0bcd873b9123e48ee7fc
diff --git a/core/api/src/main/java/org/onosproject/net/optical/device/OtuPortHelper.java b/core/api/src/main/java/org/onosproject/net/optical/device/OtuPortHelper.java
new file mode 100644
index 0000000..aeac4f9
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/optical/device/OtuPortHelper.java
@@ -0,0 +1,129 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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.
+ */
+package org.onosproject.net.optical.device;
+
+import static org.slf4j.LoggerFactory.getLogger;
+
+import java.util.Optional;
+
+import org.onosproject.net.Annotations;
+import org.onosproject.net.DefaultAnnotations;
+import org.onosproject.net.Port;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.SparseAnnotations;
+import org.onosproject.net.DefaultAnnotations.Builder;
+import org.onosproject.net.OtuSignalType;
+import org.onosproject.net.device.DefaultPortDescription;
+import org.onosproject.net.device.PortDescription;
+import org.onosproject.net.optical.OtuPort;
+import org.onosproject.net.optical.impl.DefaultOtuPort;
+import org.slf4j.Logger;
+
+import com.google.common.annotations.Beta;
+
+/**
+ * OTU port related helpers.
+ */
+@Beta
+public final class OtuPortHelper {
+
+    private static final Logger log = getLogger(OtuPortHelper.class);
+
+    // Annotation keys
+    /**
+     * {@link OtuSignalType} as String.
+     */
+    private static final String SIGNAL_TYPE = "signalType";
+
+    /**
+     * Creates OTU port description based on the supplied information.
+     *
+     * @param number        port number
+     * @param isEnabled     port enabled state
+     * @param signalType    OTU client signal type
+     */
+    public static PortDescription otuPortDescription(PortNumber number,
+                                                     boolean isEnabled,
+                                                     OtuSignalType signalType) {
+        return otuPortDescription(number, isEnabled, signalType, DefaultAnnotations.EMPTY);
+    }
+
+    /**
+     * Creates OTU port description based on the supplied information.
+     *
+     * @param number        port number
+     * @param isEnabled     port enabled state
+     * @param signalType    OTU client signal type
+     * @param annotations   key/value annotations map
+     */
+    public static PortDescription otuPortDescription(PortNumber number,
+                                                     boolean isEnabled,
+                                                     OtuSignalType signalType,
+                                                     SparseAnnotations annotations) {
+        Builder builder = DefaultAnnotations.builder();
+        builder.putAll(annotations);
+
+        builder.set(SIGNAL_TYPE, signalType.toString());
+
+        long portSpeed = 0; // TODO specify appropriate value?
+        return new DefaultPortDescription(number,
+                                          isEnabled,
+                                          Port.Type.OTU,
+                                          portSpeed,
+                                          builder.build());
+    }
+
+    /**
+     * Creates OTU port description based on the supplied information.
+     *
+     * @param base          PortDescription to get basic information from
+     * @param signalType    OTU client signal type
+     * @param annotations   key/value annotations map
+     */
+    public static PortDescription otuPortDescription(PortDescription base,
+                                                     OtuSignalType signalType,
+                                                     SparseAnnotations annotations) {
+        return otuPortDescription(base.portNumber(), base.isEnabled(), signalType, annotations);
+    }
+
+    public static Optional<OtuPort> asOtuPort(Port port) {
+        if (port instanceof OtuPort) {
+            return Optional.of((OtuPort) port);
+        }
+
+        try {
+            Annotations an = port.annotations();
+
+            OtuSignalType signalType = Enum.valueOf(OtuSignalType.class,
+                                                    an.value(SIGNAL_TYPE));
+
+
+            // Note: OTU specific annotations is not filtered-out here.
+            //       DefaultOtuPort should filter them, if necessary.
+            return Optional.of(new DefaultOtuPort(port, signalType));
+
+        } catch (NullPointerException | IllegalArgumentException e) {
+
+            log.warn("{} was not well-formed Otu port.", port, e);
+            return Optional.empty();
+        }
+    }
+
+
+    // not meant to be instantiated
+    private OtuPortHelper() {}
+
+}