Create basic structure of pap component

1) Creating the basic code structure of pap component which includes
main sub-module having Main, PapActivator, PapCommandLineArguments,
PapParameterGroup & PapParameterHandler. Along with few exception
classes. Basicalliy the structure follows the pattern developed in
policy/distribution component.

2) Created the related unit test cases and required test resources.

Change-Id: I67c82f9d072e6c8a306cb983accb693da70e58a2
Issue-ID: POLICY-1476
Signed-off-by: ramverma <ram.krishna.verma@est.tech>

1 files changed, 130 insertions, 0 deletions

diff --git a/main/src/main/java/org/onap/policy/pap/main/startstop/PapActivator.java b/main/src/main/java/org/onap/policy/pap/main/startstop/PapActivator.java
new file mode 100644
index 00000000..8aec2adf
--- /dev/null
+++ b/main/src/main/java/org/onap/policy/pap/main/startstop/PapActivator.java
@@ -0,0 +1,130 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2019 Nordix 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.pap.main.startstop;
+
+import org.onap.policy.common.parameters.ParameterService;
+import org.onap.policy.pap.main.PolicyPapException;
+import org.onap.policy.pap.main.parameters.PapParameterGroup;
+import org.slf4j.ext.XLogger;
+import org.slf4j.ext.XLoggerFactory;
+
+/**
+ * This class wraps a distributor so that it can be activated as a complete service together with all its pap and
+ * forwarding handlers.
+ *
+ * @author Ram Krishna Verma (ram.krishna.verma@est.tech)
+ */
+public class PapActivator {
+    // The logger for this class
+    private static final XLogger LOGGER = XLoggerFactory.getXLogger(PapActivator.class);
+
+    // The parameters of this policy pap activator
+    private final PapParameterGroup papParameterGroup;
+
+    private static boolean alive = false;
+
+    /**
+     * Instantiate the activator for policy pap as a complete service.
+     *
+     * @param papParameterGroup the parameters for the pap service
+     */
+    public PapActivator(final PapParameterGroup papParameterGroup) {
+        this.papParameterGroup = papParameterGroup;
+    }
+
+    /**
+     * Initialize pap as a complete service.
+     *
+     * @throws PolicyPapException on errors in initializing the service
+     */
+    public void initialize() throws PolicyPapException {
+        try {
+            LOGGER.debug("Policy pap starting as a service . . .");
+            registerToParameterService(papParameterGroup);
+            PapActivator.setAlive(true);
+            LOGGER.debug("Policy pap started as a service");
+        } catch (final Exception exp) {
+            LOGGER.error("Policy pap service startup failed", exp);
+            throw new PolicyPapException(exp.getMessage(), exp);
+        }
+    }
+
+    /**
+     * Terminate policy pap.
+     *
+     * @throws PolicyPapException on errors in terminating the service
+     */
+    public void terminate() throws PolicyPapException {
+        try {
+            deregisterToParameterService(papParameterGroup);
+            PapActivator.setAlive(false);
+
+        } catch (final Exception exp) {
+            LOGGER.error("Policy pap service termination failed", exp);
+            throw new PolicyPapException(exp.getMessage(), exp);
+        }
+    }
+
+    /**
+     * Get the parameters used by the activator.
+     *
+     * @return the parameters of the activator
+     */
+    public PapParameterGroup getParameterGroup() {
+        return papParameterGroup;
+    }
+
+    /**
+     * Method to register the parameters to Common Parameter Service.
+     *
+     * @param papParameterGroup the pap parameter group
+     */
+    public void registerToParameterService(final PapParameterGroup papParameterGroup) {
+        ParameterService.register(papParameterGroup);
+    }
+
+    /**
+     * Method to deregister the parameters from Common Parameter Service.
+     *
+     * @param papParameterGroup the pap parameter group
+     */
+    public void deregisterToParameterService(final PapParameterGroup papParameterGroup) {
+        ParameterService.deregister(papParameterGroup.getName());
+    }
+
+    /**
+     * Returns the alive status of pap service.
+     *
+     * @return the alive
+     */
+    public static boolean isAlive() {
+        return alive;
+    }
+
+    /**
+     * Change the alive status of pap service.
+     *
+     * @param status the status
+     */
+    public static void setAlive(final boolean status) {
+        alive = status;
+    }
+}