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 org.apache.asterix.metadata.declared;
  
  import org.apache.asterix.common.metadata.DataverseName;
  import org.apache.asterix.metadata.entities.Index;
  import org.apache.hyracks.algebricks.core.algebra.metadata.IDataSource;
  import org.apache.hyracks.algebricks.core.algebra.metadata.IDataSourceIndex;
  
  public class DataSourceIndex implements IDataSourceIndex<String, DataSourceId> {
  
      private final Index index;
      private final String database;
      private final DataverseName dataverseName;
      private final String datasetName;
      private final MetadataProvider metadataProvider;
  
      // Every transactions needs to work with its own instance of an
      // MetadataProvider.
      public DataSourceIndex(Index index, String database, DataverseName dataverseName, String datasetName,
              MetadataProvider metadataProvider) {
          this.index = index;
          this.database = database;
          this.dataverseName = dataverseName;
          this.datasetName = datasetName;
          this.metadataProvider = metadataProvider;
      }
  
      // TODO: Maybe Index can directly implement IDataSourceIndex<String, DataSourceId>
      @Override
      public IDataSource<DataSourceId> getDataSource() {
          try {
              DataSourceId sourceId = new DataSourceId(database, dataverseName, datasetName);
              return metadataProvider.lookupSourceInMetadata(sourceId);
          } catch (Exception me) {
              return null;
          }
      }
  
      @Override
      public String getId() {
          return index.getIndexName();
      }
  
      public Index getIndex() {
          return index;
      }
  }
  