[ONOS-7683] Implement various default telemetry configs

Change-Id: Ibfd222be32e9fb7cb29833f9b0d369abaa6e814d
diff --git a/apps/openstacktelemetry/app/src/main/java/org/onosproject/openstacktelemetry/config/DefaultKafkaTelemetryConfig.java b/apps/openstacktelemetry/app/src/main/java/org/onosproject/openstacktelemetry/config/DefaultKafkaTelemetryConfig.java
new file mode 100644
index 0000000..9dc460a
--- /dev/null
+++ b/apps/openstacktelemetry/app/src/main/java/org/onosproject/openstacktelemetry/config/DefaultKafkaTelemetryConfig.java
@@ -0,0 +1,229 @@
+/*
+ * Copyright 2018-present Open Networking 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.
+ */
+package org.onosproject.openstacktelemetry.config;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.Maps;
+import org.onosproject.openstacktelemetry.api.config.KafkaTelemetryConfig;
+
+import java.util.Map;
+import java.util.Objects;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * A configuration file contains Kafka telemetry parameters.
+ */
+public final class DefaultKafkaTelemetryConfig implements KafkaTelemetryConfig {
+
+    private final String address;
+    private final int port;
+    private final int retries;
+    private final String requiredAcks;
+    private final int batchSize;
+    private final int lingerMs;
+    private final int memoryBuffer;
+    private final String keySerializer;
+    private final String valueSerializer;
+    private final Map<String, Object> configMap;
+
+    private DefaultKafkaTelemetryConfig(String address, int port, int retries,
+                                        String requiredAcks, int batchSize,
+                                        int lingerMs, int memoryBuffer,
+                                        String keySerializer,
+                                        String valueSerializer,
+                                        Map<String, Object> configMap) {
+        this.address = address;
+        this.port = port;
+        this.retries = retries;
+        this.requiredAcks = requiredAcks;
+        this.batchSize = batchSize;
+        this.lingerMs = lingerMs;
+        this.memoryBuffer = memoryBuffer;
+        this.keySerializer = keySerializer;
+        this.valueSerializer = valueSerializer;
+        this.configMap = configMap;
+    }
+
+    @Override
+    public String address() {
+        return address;
+    }
+
+    @Override
+    public int port() {
+        return port;
+    }
+
+    @Override
+    public int retries() {
+        return retries;
+    }
+
+    @Override
+    public String requiredAcks() {
+        return requiredAcks;
+    }
+
+    @Override
+    public int batchSize() {
+        return batchSize;
+    }
+
+    @Override
+    public int lingerMs() {
+        return lingerMs;
+    }
+
+    @Override
+    public int memoryBuffer() {
+        return memoryBuffer;
+    }
+
+    @Override
+    public String keySerializer() {
+        return keySerializer;
+    }
+
+    @Override
+    public String valueSerializer() {
+        return valueSerializer;
+    }
+
+    @Override
+    public Map<String, Object> configMap() {
+        if (configMap != null) {
+            return ImmutableMap.copyOf(configMap);
+        } else {
+            return Maps.newConcurrentMap();
+        }
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+
+        if (obj instanceof DefaultKafkaTelemetryConfig) {
+            final DefaultKafkaTelemetryConfig other = (DefaultKafkaTelemetryConfig) obj;
+            return Objects.equals(this.address, other.address) &&
+                    Objects.equals(this.port, other.port) &&
+                    Objects.equals(this.retries, other.retries) &&
+                    Objects.equals(this.requiredAcks, other.requiredAcks) &&
+                    Objects.equals(this.batchSize, other.batchSize) &&
+                    Objects.equals(this.lingerMs, other.lingerMs) &&
+                    Objects.equals(this.memoryBuffer, other.memoryBuffer) &&
+                    Objects.equals(this.keySerializer, other.keySerializer) &&
+                    Objects.equals(this.valueSerializer, other.valueSerializer) &&
+                    Objects.equals(this.configMap, other.configMap);
+        }
+        return false;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(address, port, retries, requiredAcks, batchSize,
+                lingerMs, memoryBuffer, keySerializer, valueSerializer, configMap);
+    }
+
+    /**
+     * Builder class of DefaultKafkaTelemetryConfig.
+     */
+    public final class DefaultBuilder implements Builder {
+        private String address;
+        private int port;
+        private int retries;
+        private String requiredAcks;
+        private int batchSize;
+        private int lingerMs;
+        private int memoryBuffer;
+        private String keySerializer;
+        private String valueSerializer;
+        private Map<String, Object> configMap;
+
+        @Override
+        public Builder withAddress(String address) {
+            this.address = address;
+            return this;
+        }
+
+        @Override
+        public Builder withPort(int port) {
+            this.port = port;
+            return this;
+        }
+
+        @Override
+        public Builder withRetries(int retries) {
+            this.retries = retries;
+            return this;
+        }
+
+        @Override
+        public Builder withRequiredAcks(String requiredAcks) {
+            this.requiredAcks = requiredAcks;
+            return this;
+        }
+
+        @Override
+        public Builder withBatchSize(int batchSize) {
+            this.batchSize = batchSize;
+            return this;
+        }
+
+        @Override
+        public Builder withLingerMs(int lingerMs) {
+            this.lingerMs = lingerMs;
+            return this;
+        }
+
+        @Override
+        public Builder withMemoryBuffer(int memoryBuffer) {
+            this.memoryBuffer = memoryBuffer;
+            return this;
+        }
+
+        @Override
+        public Builder withKeySerializer(String keySerializer) {
+            this.keySerializer = keySerializer;
+            return this;
+        }
+
+        @Override
+        public Builder withValueSerializer(String valueSerializer) {
+            this.valueSerializer = valueSerializer;
+            return this;
+        }
+
+        @Override
+        public Builder withConfigMap(Map<String, Object> configMap) {
+            this.configMap = configMap;
+            return this;
+        }
+
+        @Override
+        public KafkaTelemetryConfig build() {
+            checkNotNull(address, "Kafka server address cannot be null");
+            checkNotNull(keySerializer, "Kafka key serializer cannot be null");
+            checkNotNull(valueSerializer, "Kafka value serializer cannot be null");
+
+            return new DefaultKafkaTelemetryConfig(address, port, retries,
+                                requiredAcks, batchSize, lingerMs, memoryBuffer,
+                                keySerializer, valueSerializer, configMap);
+        }
+    }
+}