equals.java

java1.6众多例子参考

/*
 * Copyright 1999-2004 The Apache Software Foundation.
 *
 * Licensed 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.
 */
/*
 * $Id: Equals.java,v 1.2.4.1 2005/09/14 21:31:44 jeffsuttor Exp $
 */
package com.sun.org.apache.xpath.internal.operations;

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

/**
 * The '=' operation expression executer.
 */
public class Equals extends Operation
{
    static final long serialVersionUID = -2658315633903426134L;

  /**
   * 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 left.equals(right) ? XBoolean.S_TRUE : XBoolean.S_FALSE;
  }
  
  /**
   * Execute a binary operation by calling execute on each of the operands,
   * and then calling the operate method on the derived class.
   *
   *
   * @param xctxt The runtime execution context.
   *
   * @return The XObject result of the operation.
   *
   * @throws javax.xml.transform.TransformerException
   */
  public boolean bool(XPathContext xctxt)
          throws javax.xml.transform.TransformerException
  {
    XObject left = m_left.execute(xctxt, true);
    XObject right = m_right.execute(xctxt, true);

    boolean result = left.equals(right) ? true : false;
	left.detach();
	right.detach();
    return result;
  }

}