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.enumerable.impl;
  
  import org.apache.calcite.adapter.enumerable.AggResetContext;
  import org.apache.calcite.adapter.enumerable.NestedBlockBuilderImpl;
  import org.apache.calcite.linq4j.tree.BlockBuilder;
  import org.apache.calcite.linq4j.tree.Expression;
  import org.apache.calcite.rel.core.AggregateCall;
  
  import java.util.List;
  
  /**
   * Implementation of
   * {@link org.apache.calcite.adapter.enumerable.AggResetContext}.
   */
  public abstract class AggResetContextImpl extends NestedBlockBuilderImpl
      implements AggResetContext {
    private final List<Expression> accumulator;
  
    /**
     * Creates aggregate reset context.
     *
     * @param block Code block that will contain the added initialization
     * @param accumulator Accumulator variables that store the intermediate
     *                    aggregate state
     */
    protected AggResetContextImpl(BlockBuilder block, List<Expression> accumulator) {
      super(block);
      this.accumulator = accumulator;
    }
  
    @Override public List<Expression> accumulator() {
      return accumulator;
    }
  
    public AggregateCall call() {
      throw new UnsupportedOperationException();
    }
  }
  