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, 489 insertions, 0 deletions

diff --git a/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/TopicEndpointProxy.java b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/TopicEndpointProxy.java
new file mode 100644
index 00000000..9912761f
--- /dev/null
+++ b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/TopicEndpointProxy.java
@@ -0,0 +1,489 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2017-2019 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;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Properties;
+import org.onap.policy.common.capabilities.Startable;
+import org.onap.policy.common.endpoints.event.comm.bus.DmaapTopicSink;
+import org.onap.policy.common.endpoints.event.comm.bus.DmaapTopicSource;
+import org.onap.policy.common.endpoints.event.comm.bus.NoopTopicSink;
+import org.onap.policy.common.endpoints.event.comm.bus.NoopTopicSource;
+import org.onap.policy.common.endpoints.event.comm.bus.UebTopicSink;
+import org.onap.policy.common.endpoints.event.comm.bus.UebTopicSource;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * This implementation of the Topic Endpoint Manager, proxies operations to the appropriate
+ * implementation(s).
+ */
+class TopicEndpointProxy implements TopicEndpoint {
+    /**
+     * Logger.
+     */
+    private static final Logger logger = LoggerFactory.getLogger(TopicEndpointProxy.class);
+
+    /**
+     * Is this element locked boolean.
+     */
+    private volatile boolean locked = false;
+
+    /**
+     * Is this element alive boolean.
+     */
+    private volatile boolean alive = false;
+
+    @Override
+    public List<TopicSource> addTopicSources(Properties properties) {
+
+        // 1. Create UEB Sources
+        // 2. Create DMAAP Sources
+        // 3. Create NOOP Sources
+
+        List<TopicSource> sources = new ArrayList<>();
+
+        sources.addAll(UebTopicSource.factory.build(properties));
+        sources.addAll(DmaapTopicSource.factory.build(properties));
+        sources.addAll(NoopTopicSource.factory.build(properties));
+
+        if (this.isLocked()) {
+            for (final TopicSource source : sources) {
+                source.lock();
+            }
+        }
+
+        return sources;
+    }
+
+    @Override
+    public List<TopicSink> addTopicSinks(Properties properties) {
+        // 1. Create UEB Sinks
+        // 2. Create DMAAP Sinks
+        // 3. Create NOOP Sinks
+
+        final List<TopicSink> sinks = new ArrayList<>();
+
+        sinks.addAll(UebTopicSink.factory.build(properties));
+        sinks.addAll(DmaapTopicSink.factory.build(properties));
+        sinks.addAll(NoopTopicSink.factory.build(properties));
+
+        if (this.isLocked()) {
+            for (final TopicSink sink : sinks) {
+                sink.lock();
+            }
+        }
+
+        return sinks;
+    }
+
+    @Override
+    public List<TopicSource> getTopicSources() {
+
+        final List<TopicSource> sources = new ArrayList<>();
+
+        sources.addAll(UebTopicSource.factory.inventory());
+        sources.addAll(DmaapTopicSource.factory.inventory());
+        sources.addAll(NoopTopicSource.factory.inventory());
+
+        return sources;
+    }
+
+    @Override
+    public List<TopicSource> getTopicSources(List<String> topicNames) {
+
+        if (topicNames == null) {
+            throw new IllegalArgumentException("must provide a list of topics");
+        }
+
+        final List<TopicSource> sources = new ArrayList<>();
+        for (final String topic : topicNames) {
+            try {
+                final TopicSource uebSource = this.getUebTopicSource(topic);
+                if (uebSource != null) {
+                    sources.add(uebSource);
+                }
+            } catch (final Exception e) {
+                logger.debug("No UEB source for topic: {}", topic, e);
+            }
+
+            try {
+                final TopicSource dmaapSource = this.getDmaapTopicSource(topic);
+                if (dmaapSource != null) {
+                    sources.add(dmaapSource);
+                }
+            } catch (final Exception e) {
+                logger.debug("No DMAAP source for topic: {}", topic, e);
+            }
+
+            try {
+                final TopicSource noopSource = this.getNoopTopicSource(topic);
+                if (noopSource != null) {
+                    sources.add(noopSource);
+                }
+            } catch (final Exception e) {
+                logger.debug("No NOOP source for topic: {}", topic, e);
+            }
+        }
+        return sources;
+    }
+
+    @Override
+    public List<TopicSink> getTopicSinks() {
+
+        final List<TopicSink> sinks = new ArrayList<>();
+
+        sinks.addAll(UebTopicSink.factory.inventory());
+        sinks.addAll(DmaapTopicSink.factory.inventory());
+        sinks.addAll(NoopTopicSink.factory.inventory());
+
+        return sinks;
+    }
+
+    @Override
+    public List<TopicSink> getTopicSinks(List<String> topicNames) {
+
+        if (topicNames == null) {
+            throw new IllegalArgumentException("must provide a list of topics");
+        }
+
+        final List<TopicSink> sinks = new ArrayList<>();
+        for (final String topic : topicNames) {
+            try {
+                final TopicSink uebSink = this.getUebTopicSink(topic);
+                if (uebSink != null) {
+                    sinks.add(uebSink);
+                }
+            } catch (final Exception e) {
+                logger.debug("No UEB sink for topic: {}", topic, e);
+            }
+
+            try {
+                final TopicSink dmaapSink = this.getDmaapTopicSink(topic);
+                if (dmaapSink != null) {
+                    sinks.add(dmaapSink);
+                }
+            } catch (final Exception e) {
+                logger.debug("No DMAAP sink for topic: {}", topic, e);
+            }
+
+            try {
+                final TopicSink noopSink = this.getNoopTopicSink(topic);
+                if (noopSink != null) {
+                    sinks.add(noopSink);
+                }
+            } catch (final Exception e) {
+                logger.debug("No NOOP sink for topic: {}", topic, e);
+            }
+        }
+        return sinks;
+    }
+
+    @Override
+    public List<TopicSink> getTopicSinks(String topicName) {
+        if (topicName == null) {
+            throw parmException(null);
+        }
+
+        final List<TopicSink> sinks = new ArrayList<>();
+
+        try {
+            sinks.add(this.getUebTopicSink(topicName));
+        } catch (final Exception e) {
+            logNoSink(topicName, e);
+        }
+
+        try {
+            sinks.add(this.getDmaapTopicSink(topicName));
+        } catch (final Exception e) {
+            logNoSink(topicName, e);
+        }
+
+        try {
+            sinks.add(this.getNoopTopicSink(topicName));
+        } catch (final Exception e) {
+            logNoSink(topicName, e);
+        }
+
+        return sinks;
+    }
+
+    @JsonIgnore
+    @Override
+    public List<UebTopicSource> getUebTopicSources() {
+        return UebTopicSource.factory.inventory();
+    }
+
+    @JsonIgnore
+    @Override
+    public List<DmaapTopicSource> getDmaapTopicSources() {
+        return DmaapTopicSource.factory.inventory();
+    }
+
+    @Override
+    public List<NoopTopicSource> getNoopTopicSources() {
+        return NoopTopicSource.factory.inventory();
+    }
+
+    @JsonIgnore
+    @Override
+    public List<UebTopicSink> getUebTopicSinks() {
+        return UebTopicSink.factory.inventory();
+    }
+
+    @JsonIgnore
+    @Override
+    public List<DmaapTopicSink> getDmaapTopicSinks() {
+        return DmaapTopicSink.factory.inventory();
+    }
+
+    @JsonIgnore
+    @Override
+    public List<NoopTopicSink> getNoopTopicSinks() {
+        return NoopTopicSink.factory.inventory();
+    }
+
+    @Override
+    public boolean start() {
+
+        synchronized (this) {
+            if (this.locked) {
+                throw new IllegalStateException(this + " is locked");
+            }
+
+            if (this.alive) {
+                return true;
+            }
+
+            this.alive = true;
+        }
+
+        final List<Startable> endpoints = this.getEndpoints();
+
+        boolean success = true;
+        for (final Startable endpoint : endpoints) {
+            try {
+                success = endpoint.start() && success;
+            } catch (final Exception e) {
+                success = false;
+                logger.error("Problem starting endpoint: {}", endpoint, e);
+            }
+        }
+
+        return success;
+    }
+
+    @Override
+    public boolean stop() {
+
+        /*
+         * stop regardless if it is locked, in other words, stop operation has precedence over
+         * locks.
+         */
+        synchronized (this) {
+            this.alive = false;
+        }
+
+        final List<Startable> endpoints = this.getEndpoints();
+
+        boolean success = true;
+        for (final Startable endpoint : endpoints) {
+            try {
+                success = endpoint.stop() && success;
+            } catch (final Exception e) {
+                success = false;
+                logger.error("Problem stopping endpoint: {}", endpoint, e);
+            }
+        }
+
+        return success;
+    }
+
+    /**
+     * Gets the endpoints.
+     *
+     * @return list of managed endpoints
+     */
+    @JsonIgnore
+    protected List<Startable> getEndpoints() {
+        final List<Startable> endpoints = new ArrayList<>();
+
+        endpoints.addAll(this.getTopicSources());
+        endpoints.addAll(this.getTopicSinks());
+
+        return endpoints;
+    }
+
+    @Override
+    public void shutdown() {
+        this.stop();
+
+        UebTopicSource.factory.destroy();
+        UebTopicSink.factory.destroy();
+
+        DmaapTopicSource.factory.destroy();
+        DmaapTopicSink.factory.destroy();
+
+        NoopTopicSink.factory.destroy();
+        NoopTopicSource.factory.destroy();
+
+    }
+
+    @Override
+    public boolean isAlive() {
+        return this.alive;
+    }
+
+    @Override
+    public boolean lock() {
+
+        synchronized (this) {
+            if (this.locked) {
+                return true;
+            }
+
+            this.locked = true;
+        }
+
+        for (final TopicSource source : this.getTopicSources()) {
+            source.lock();
+        }
+
+        for (final TopicSink sink : this.getTopicSinks()) {
+            sink.lock();
+        }
+
+        return true;
+    }
+
+    @Override
+    public boolean unlock() {
+        synchronized (this) {
+            if (!this.locked) {
+                return true;
+            }
+
+            this.locked = false;
+        }
+
+        for (final TopicSource source : this.getTopicSources()) {
+            source.unlock();
+        }
+
+        for (final TopicSink sink : this.getTopicSinks()) {
+            sink.unlock();
+        }
+
+        return true;
+    }
+
+    @Override
+    public boolean isLocked() {
+        return this.locked;
+    }
+
+    @Override
+    public TopicSource getTopicSource(Topic.CommInfrastructure commType, String topicName) {
+
+        if (commType == null) {
+            throw parmException(topicName);
+        }
+
+        if (topicName == null) {
+            throw parmException(null);
+        }
+
+        switch (commType) {
+            case UEB:
+                return this.getUebTopicSource(topicName);
+            case DMAAP:
+                return this.getDmaapTopicSource(topicName);
+            case NOOP:
+                return this.getNoopTopicSource(topicName);
+            default:
+                throw new UnsupportedOperationException("Unsupported " + commType.name());
+        }
+    }
+
+    @Override
+    public TopicSink getTopicSink(Topic.CommInfrastructure commType, String topicName) {
+        if (commType == null) {
+            throw parmException(topicName);
+        }
+
+        if (topicName == null) {
+            throw parmException(null);
+        }
+
+        switch (commType) {
+            case UEB:
+                return this.getUebTopicSink(topicName);
+            case DMAAP:
+                return this.getDmaapTopicSink(topicName);
+            case NOOP:
+                return this.getNoopTopicSink(topicName);
+            default:
+                throw new UnsupportedOperationException("Unsupported " + commType.name());
+        }
+    }
+
+    @Override
+    public UebTopicSource getUebTopicSource(String topicName) {
+        return UebTopicSource.factory.get(topicName);
+    }
+
+    @Override
+    public UebTopicSink getUebTopicSink(String topicName) {
+        return UebTopicSink.factory.get(topicName);
+    }
+
+    @Override
+    public DmaapTopicSource getDmaapTopicSource(String topicName) {
+        return DmaapTopicSource.factory.get(topicName);
+    }
+
+    @Override
+    public NoopTopicSource getNoopTopicSource(String topicName) {
+        return NoopTopicSource.factory.get(topicName);
+    }
+
+    @Override
+    public DmaapTopicSink getDmaapTopicSink(String topicName) {
+        return DmaapTopicSink.factory.get(topicName);
+    }
+
+    @Override
+    public NoopTopicSink getNoopTopicSink(String topicName) {
+        return NoopTopicSink.factory.get(topicName);
+    }
+
+    private IllegalArgumentException parmException(String topicName) {
+        return new IllegalArgumentException(
+            "Invalid parameter: a communication infrastructure required to fetch " + topicName);
+    }
+
+    private void logNoSink(String topicName, Exception ex) {
+        logger.debug("No sink for topic: {}", topicName, ex);
+    }
+
+}
\ No newline at end of file