/*
 * 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 org.apache.phoenix.schema.export;

import java.io.IOException;
import org.apache.hadoop.conf.Configuration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public final class SchemaRegistryRepositoryFactory {
  private static final Logger LOGGER = LoggerFactory.getLogger(SchemaRegistryRepository.class);
  private static SchemaRegistryRepository exporter;

  public synchronized static SchemaRegistryRepository
    getSchemaRegistryRepository(Configuration conf) throws IOException {
    if (exporter != null) {
      return exporter;
    }
    try {
      String className = conf.get(SchemaRegistryRepository.SCHEMA_REGISTRY_IMPL_KEY);
      if (className == null) {
        exporter = new DefaultSchemaRegistryRepository();
      } else {
        Class<SchemaRegistryRepository> clazz =
          (Class<SchemaRegistryRepository>) Class.forName(className);
        exporter = clazz.newInstance();
      }
      exporter.init(conf);
      return exporter;
    } catch (Exception e) {
      LOGGER.error("Error constructing SchemaRegistryExporter object", e);
      if (exporter != null) {
        try {
          exporter.close();
          exporter = null;
        } catch (IOException innerE) {
          LOGGER.error("Error closing incorrectly constructed SchemaRegistryExporter", e);
        }
      }
      throw new IOException(e);
    }
  }

  public synchronized static void close() throws IOException {
    if (exporter != null) {
      exporter.close();
      exporter = null;
    }
  }
}
