Add PDP-TOPIC-CHECK message

Added a new PdpMessage subclass that a PDP can use to verify its ability
to send/receive to/from the PDP-PAP topic before it sends its first
registration message.

Issue-ID: POLICY-3531
Change-Id: Ied61caa805e93e25732385bf91272b4fc248fd69
Signed-off-by: Jim Hahn <jrh3@att.com>

3 files changed, 63 insertions, 4 deletions

diff --git a/models-pdp/src/main/java/org/onap/policy/models/pdp/concepts/PdpMessage.java b/models-pdp/src/main/java/org/onap/policy/models/pdp/concepts/PdpMessage.java
index 5d0359c74..219193266 100644
--- a/models-pdp/src/main/java/org/onap/policy/models/pdp/concepts/PdpMessage.java
+++ b/models-pdp/src/main/java/org/onap/policy/models/pdp/concepts/PdpMessage.java
@@ -1,7 +1,7 @@
 /*-
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2019 Nordix Foundation.
- *  Modifications Copyright (C) 2019 AT&T Intellectual Property.
+ *  Modifications Copyright (C) 2019, 2021 AT&T Intellectual Property.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,6 +23,7 @@ package org.onap.policy.models.pdp.concepts;
 
 import java.util.UUID;
 import lombok.AccessLevel;
+import lombok.EqualsAndHashCode;
 import lombok.Getter;
 import lombok.NonNull;
 import lombok.Setter;
@@ -38,6 +39,7 @@ import org.onap.policy.models.pdp.enums.PdpMessageType;
 @Getter
 @Setter
 @ToString
+@EqualsAndHashCode
 public class PdpMessage {
 
     @Setter(AccessLevel.NONE)
@@ -58,13 +60,13 @@ public class PdpMessage {
 
     /**
      * Group associated with the PDP. For state-change messages, this may be {@code null},
-     * if the {@link #name} is provided.
+     * if the {@link #name} is provided.  Also {@code null} for topic-check messages.
      */
     private String pdpGroup;
 
     /**
      * Group associated with the PDP. For state-change messages, this may be {@code null},
-     * if the {@link #name} is provided.
+     * if the {@link #name} is provided.  Also {@code null} for topic-check messages.
      */
     private String pdpSubgroup;
 
diff --git a/models-pdp/src/main/java/org/onap/policy/models/pdp/concepts/PdpTopicCheck.java b/models-pdp/src/main/java/org/onap/policy/models/pdp/concepts/PdpTopicCheck.java
new file mode 100644
index 000000000..2cd3a9d8b
--- /dev/null
+++ b/models-pdp/src/main/java/org/onap/policy/models/pdp/concepts/PdpTopicCheck.java
@@ -0,0 +1,52 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 AT&T Intellectual Property.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.models.pdp.concepts;
+
+import lombok.Getter;
+import lombok.Setter;
+import lombok.ToString;
+import org.onap.policy.models.pdp.enums.PdpMessageType;
+
+/**
+ * Class to represent the PDP_TOPIC_CHECK message that a PDP will send to itself.
+ */
+@Getter
+@Setter
+@ToString(callSuper = true)
+public class PdpTopicCheck extends PdpMessage {
+
+    /**
+     * Constructs the object.
+     *
+     */
+    public PdpTopicCheck() {
+        super(PdpMessageType.PDP_TOPIC_CHECK);
+    }
+
+    /**
+     * Constructs the object, making a deep copy.
+     *
+     * @param source source from which to copy
+     */
+    public PdpTopicCheck(PdpTopicCheck source) {
+        super(source);
+    }
+}
diff --git a/models-pdp/src/main/java/org/onap/policy/models/pdp/enums/PdpMessageType.java b/models-pdp/src/main/java/org/onap/policy/models/pdp/enums/PdpMessageType.java
index 7ba4ad73e..a8aad9667 100644
--- a/models-pdp/src/main/java/org/onap/policy/models/pdp/enums/PdpMessageType.java
+++ b/models-pdp/src/main/java/org/onap/policy/models/pdp/enums/PdpMessageType.java
@@ -1,7 +1,7 @@
 /*-
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2019 Nordix Foundation.
- *  Modifications Copyright (C) 2019 AT&T Intellectual Property.
+ *  Modifications Copyright (C) 2019, 2021 AT&T Intellectual Property.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -50,4 +50,9 @@ public enum PdpMessageType {
      * PDP_HEALTH_CHECK operation.
      */
     PDP_HEALTH_CHECK,
+
+    /**
+     * Used by PDPs to check their ability to send and receive messages on the PDP-PAP topic.
+     */
+    PDP_TOPIC_CHECK,
 }