/*
 * 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.expression;

import java.math.BigDecimal;
import java.util.List;
import org.apache.phoenix.expression.visitor.ExpressionVisitor;
import org.apache.phoenix.query.QueryConstants;

/**
 * Subtract expression implementation
 * @since 0.1
 */
public abstract class SubtractExpression extends BaseAddSubtractExpression {
  protected static final BigDecimal BD_MILLIS_IN_DAY =
    BigDecimal.valueOf(QueryConstants.MILLIS_IN_DAY);

  public SubtractExpression() {
  }

  public SubtractExpression(List<Expression> children) {
    super(children);
  }

  @Override
  public final <T> T accept(ExpressionVisitor<T> visitor) {
    List<T> l = acceptChildren(visitor, visitor.visitEnter(this));
    T t = visitor.visitLeave(this, l);
    if (t == null) {
      t = visitor.defaultReturn(this, l);
    }
    return t;
  }

  @Override
  public String getOperatorString() {
    return " - ";
  }
}
