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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * 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.

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package com.sun.org.apache.xpath.internal.operations;

import com.sun.org.apache.xpath.internal.XPathContext;

import com.sun.org.apache.xpath.internal.objects.XNumber;

import com.sun.org.apache.xpath.internal.objects.XObject;

/**

 * The binary '-' operation expression executer.

 */

public class Minus extends Operation

{

    static final long serialVersionUID = -5297672838170871043L;

  /**

   * Apply the operation to two operands, and return the result.

   *

   *

   * @param left non-null reference to the evaluated left operand.

   * @param right non-null reference to the evaluated right operand.

   *

   * @return non-null reference to the XObject that represents the

   *         result of the operation.

   *

   * @throws javax.xml.transform.TransformerException

   */

  public XObject operate(XObject left, XObject right)

          throws javax.xml.transform.TransformerException

  {

    return new XNumber(left.num() - right.num());

  }

  /**

   * Evaluate this operation directly to a double.

   *

   * @param xctxt The runtime execution context.

   *

   * @return The result of the operation as a double.

   *

   * @throws javax.xml.transform.TransformerException

   */

  public double num(XPathContext xctxt)

          throws javax.xml.transform.TransformerException

  {

    return (m_left.num(xctxt) - m_right.num(xctxt));

  }

}