simplelexicalanalysis.java

来自「<算法导论>第二版大部分算法实现. 1. 各类排序和顺序统计学相关」· Java 代码 · 共 34 行

/*
 * Copyright (C) 2003-2008 Wang Pengcheng <[e-mail]>
 * Permission is granted to copy, distribute and/or modify this
 * document under the terms of the GNU Free Documentation License,
 * Version 2.0 or any later version published by the Free Software Foundation;
 * with no Invariant Sections.
 * You may obtain a copy of the License at
 *   http://www.gnu.org/licenses/lgpl.txt
 */
//26 Feb 2008
package cn.edu.whu.iss.algorithm.unit10.expression.lexical;

public class SimpleLexicalAnalysis extends AbstractLexicalAnalysis {

	public SimpleLexicalAnalysis() {
		super();
	}

	public SimpleLexicalAnalysis(String expression) {
		super(expression);
	}

	protected String analyseExpr() {
		String expr = this.expression;
		for (int i = expression.length() - 1; i >= 0; i--) {
			if (!isPermitChar(expression.charAt(i))) {
				expr = expr.substring(0, i) + expr.substring(i + 1);
			}
		}
		return expr;
	}

}