Adding NOOP sources support

In addition, Noop* classes have been refactored to
increase code reuse and clean some checkstyle issues.
Additional Junits have been added for existing functionality.

Change-Id: I072f9ff2f415630ac82eca949a8360249f73da86
Issue-ID: POLICY-1397
Signed-off-by: Jorge Hernandez <jorge.hernandez-herrero@att.com>

1 files changed, 144 insertions, 0 deletions

diff --git a/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/bus/NoopTopicEndpoint.java b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/bus/NoopTopicEndpoint.java
new file mode 100644
index 00000000..091e46bf
--- /dev/null
+++ b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/bus/NoopTopicEndpoint.java
@@ -0,0 +1,144 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2019 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.endpoints.event.comm.bus;
+
+import java.util.List;
+import org.onap.policy.common.endpoints.event.comm.bus.internal.TopicBase;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * No Operation topic endpoint.
+ */
+public abstract class NoopTopicEndpoint extends TopicBase {
+
+    /**
+     * Logger.
+     */
+    private static Logger logger = LoggerFactory.getLogger(NoopTopicEndpoint.class);
+
+    /**
+     * Network logger.
+     */
+    private static final Logger netLogger = LoggerFactory.getLogger(NETWORK_LOGGER);
+
+    /**
+     * {@inheritDoc}.
+     */
+    public NoopTopicEndpoint(List<String> servers, String topic) {
+        super(servers, topic);
+    }
+
+    /**
+     *  I/O.
+     *
+     * @param message message.
+     * @return true if sucessful.
+     */
+    protected boolean io(String message) {
+
+        if (message == null || message.isEmpty()) {
+            throw new IllegalArgumentException("Message is empty");
+        }
+
+        if (!this.alive) {
+            throw new IllegalStateException(this + " is stopped");
+        }
+
+        try {
+            synchronized (this) {
+                this.recentEvents.add(message);
+            }
+
+            netLogger.info("[OUT|{}|{}]{}{}", this.getTopicCommInfrastructure(), this.topic, System.lineSeparator(),
+                    message);
+
+            broadcast(message);
+        } catch (Exception e) {
+            logger.warn("{}: cannot send because of {}", this, e.getMessage(), e);
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * {@inheritDoc}.
+     */
+    @Override
+    public CommInfrastructure getTopicCommInfrastructure() {
+        return CommInfrastructure.NOOP;
+    }
+
+    /**
+     * {@inheritDoc}.
+     */
+    @Override
+    public boolean start() {
+        logger.info("{}: starting", this);
+
+        synchronized (this) {
+
+            if (this.alive) {
+                return true;
+            }
+
+            if (locked) {
+                throw new IllegalStateException(this + " is locked.");
+            }
+
+            this.alive = true;
+        }
+
+        return true;
+    }
+
+    /**
+     * {@inheritDoc}.
+     */
+    @Override
+    public boolean stop() {
+        logger.info("{}: stopping", this);
+
+        synchronized (this) {
+            this.alive = false;
+        }
+        return true;
+    }
+
+    /**
+     * {@inheritDoc}.
+     */
+    @Override
+    public void shutdown() {
+        logger.info("{}: shutdown", this);
+
+        this.stop();
+    }
+
+    /**
+     * {@inheritDoc}.
+     */
+    @Override
+    public String toString() {
+        return "NoopTopicEndpoint[" + super.toString() + "]";
+    }
+}