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.calcite.adapter.jdbc;
  
  import org.apache.calcite.linq4j.Enumerator;
  import org.apache.calcite.linq4j.QueryProvider;
  import org.apache.calcite.linq4j.QueryProviderImpl;
  import org.apache.calcite.linq4j.Queryable;
  
  import static org.apache.calcite.linq4j.Nullness.castNonNull;
  
  /**
   * Implementation of {@link QueryProvider} that talks to JDBC databases.
   */
  public final class JdbcQueryProvider extends QueryProviderImpl {
    public static final JdbcQueryProvider INSTANCE = new JdbcQueryProvider();
  
    private JdbcQueryProvider() {
    }
  
    @Override public <T> Enumerator<T> executeQuery(Queryable<T> queryable) {
      return castNonNull(null);
    }
  }
  