content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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 com.datastax.oss.driver.internal.osgi.service;
  
  import static com.datastax.oss.driver.api.querybuilder.QueryBuilder.bindMarker;
  import static com.datastax.oss.driver.api.querybuilder.QueryBuilder.deleteFrom;
  import static com.datastax.oss.driver.api.querybuilder.relation.Relation.column;
  
  import com.codahale.metrics.Timer;
  import com.datastax.oss.driver.api.core.CqlIdentifier;
  import com.datastax.oss.driver.api.core.CqlSession;
  import com.datastax.oss.driver.api.core.cql.BoundStatement;
  import com.datastax.oss.driver.api.core.cql.PreparedStatement;
  import com.datastax.oss.driver.api.core.metrics.DefaultSessionMetric;
  import com.datastax.oss.driver.api.core.metrics.Metrics;
  import com.datastax.oss.driver.api.osgi.service.MailboxException;
  import com.datastax.oss.driver.api.osgi.service.MailboxMessage;
  import com.datastax.oss.driver.api.osgi.service.MailboxService;
  import java.util.Optional;
  import net.jcip.annotations.GuardedBy;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  public class MailboxServiceImpl implements MailboxService {
  
    private static final Logger LOGGER = LoggerFactory.getLogger(MailboxServiceImpl.class);
  
    protected final CqlSession session;
    protected final CqlIdentifier keyspace;
  
    @GuardedBy("this")
    protected boolean initialized = false;
  
    private PreparedStatement deleteStatement;
  
    protected MailboxMessageDao dao;
  
    public MailboxServiceImpl(CqlSession session, CqlIdentifier keyspace) {
      this.session = session;
      this.keyspace = keyspace;
    }
  
    public synchronized void init() {
      if (initialized) {
        return;
      }
      createSchema();
      prepareStatements();
      createDaos();
      printMetrics();
      initialized = true;
    }
  
    protected void createSchema() {
      session.execute("DROP KEYSPACE IF EXISTS test_osgi");
      session.execute(
          "CREATE KEYSPACE IF NOT EXISTS test_osgi with replication = {'class': 'SimpleStrategy', 'replication_factor' : 1}");
      session.execute(
          "CREATE TABLE "
              + keyspace
              + "."
              + MailboxMessage.MAILBOX_TABLE
              + " ("
              + "recipient text,"
              + "timestamp timestamp,"
              + "sender text,"
              + "body text,"
              + "PRIMARY KEY (recipient, timestamp))");
    }
  
    protected void prepareStatements() {
      deleteStatement =
          session.prepare(
              deleteFrom(keyspace, MailboxMessage.MAILBOX_TABLE)
                  .where(column("recipient").isEqualTo(bindMarker()))
                  .build());
    }
  
    protected void createDaos() {
      MailboxMapper mapper = new MailboxMapperBuilder(session).build();
      dao = mapper.mailboxMessageDao(keyspace);
    }
  
    protected void printMetrics() {
      // Exercise metrics
      if (session.getMetrics().isPresent()) {
        Metrics metrics = session.getMetrics().get();
        Optional<Timer> cqlRequests = metrics.getSessionMetric(DefaultSessionMetric.CQL_REQUESTS);
        cqlRequests.ifPresent(
            counter -> LOGGER.info("Number of CQL requests: {}", counter.getCount()));
      }
    }
  
    @Override
    public Iterable<MailboxMessage> getMessages(String recipient) throws MailboxException {
      try {
        return dao.findByRecipient(recipient);
      } catch (Exception e) {
        throw new MailboxException(e);
      }
    }
  
    @Override
    public void sendMessage(MailboxMessage message) throws MailboxException {
      try {
        dao.save(message);
      } catch (Exception e) {
        throw new MailboxException(e);
      }
    }
  
    @Override
    public void clearMailbox(String recipient) throws MailboxException {
      try {
        BoundStatement statement = deleteStatement.bind(recipient);
        session.execute(statement);
      } catch (Exception e) {
        throw new MailboxException(e);
      }
    }
  }
  