/*
 * Copyright 2005-2008 Axel Kramer (axelclk@gmail.com)
 *
 * 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.
 */
package org.matheclipse.parser.client.ast;

/**
 * The basic node for storing a parsed number expression string
 * 
 */
public abstract class NumberNode extends ASTNode { 

	protected boolean sign;

	protected NumberNode(final String value) {
		super(value);
		sign = false;
	}

	public void toggleSign() {
		sign = !sign;
	}

	public String getString() {
		if (sign) {
			return "-" + fStringValue;
		}
		return fStringValue;
	}

	public String toString() {
		if (sign) {
			return "-" + fStringValue;
		}
		return fStringValue;
	}

	public boolean isSign() {
		return sign;
	}

	public double doubleValue() {
		return Double.parseDouble(toString());
	}

	public abstract boolean equals(Object obj);
	
	public int hashCode() {
		if (sign) {
			return fStringValue.hashCode() * 17;
		}
		return fStringValue.hashCode();
	}
}