001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *     http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.el;
018
019import javax.servlet.jsp.el.ELException;
020
021/**
022 *
023 * <p>This is the superclass for all unary operators
024 * 
025 * @author Nathan Abramson - Art Technology Group
026 * @version $Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author: bayard $
027 **/
028
029public abstract class UnaryOperator
030{
031  //-------------------------------------
032  /**
033   *
034   * Constructor
035   **/
036  public UnaryOperator ()
037  {
038  }
039
040  //-------------------------------------
041  // Expression methods
042  //-------------------------------------
043  /**
044   *
045   * Returns the symbol representing the operator
046   **/
047  public abstract String getOperatorSymbol ();
048
049  //-------------------------------------
050  /**
051   *
052   * Applies the operator to the given value
053   **/
054  public abstract Object apply (Object pValue)
055    throws ELException;
056
057  //-------------------------------------
058}