/* * This software and all files contained in it are distrubted under the MIT license. * * Copyright (c) 2013 Cogito Learning Ltd * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package uk.co.cogitolearning.cogpar; /** * An ExpressionNode that handles exponentiation. The node holds * a base and an exponent and calulates base^exponent * */ public class ExponentiationExpressionNode implements ExpressionNode { /** the node containing the base */ private ExpressionNode base; /** the node containing the exponent */ private ExpressionNode exponent; /** * Construct the ExponentiationExpressionNode with base and exponent * @param base the node containing the base * @param exponent the node containing the exponent */ public ExponentiationExpressionNode(ExpressionNode base, ExpressionNode exponent) { this.base = base; this.exponent = exponent; } /** * Returns the type of the node, in this case ExpressionNode.EXPONENTIATION_NODE */ public int getType() { return ExpressionNode.EXPONENTIATION_NODE; } /** * Returns the value of the sub-expression that is rooted at this node. * * Calculates base^exponent */ public double getValue() { return Math.pow(base.getValue(), exponent.getValue()); } /** * Implementation of the visitor design pattern. * * Calls visit on the visitor and then passes the visitor on to the accept * method of the base and the exponent. * * @param visitor * the visitor */ public void accept(ExpressionNodeVisitor visitor) { visitor.visit(this); base.accept(visitor); exponent.accept(visitor); } }