/*
* Copyright (C) 2008-2012 Steve Ratcliffe
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*
* Author: Steve Ratcliffe
* Create date: 10-Nov-2008
*/
package uk.me.parabola.mkgmap.osmstyle.eval;
import uk.me.parabola.mkgmap.reader.osm.Element;
/**
* Class for numeric operations.
*
* This may include Equals at some point so that you can do max_speed=20mph
* even when the tag doesn't include mph etc.
*
* @author Steve Ratcliffe
*/
public abstract class NumericOp extends AbstractBinaryOp {
/**
* This is passed the result of a compareTo and the subclass
* returns true or false depending on the operation.
*/
protected abstract boolean doesCompare(int result);
public int priority() {
return 10;
}
/**
* This evaluation routine works for all numeric tests. Implement the
* {@link #doesCompare} routine instead of this.
*/
public final boolean eval(Element el) {
// get the value of the tag, if it doesn't exist then false.
String val = first.value(el);
if (val == null)
return false;
ValueWithUnit result = new ValueWithUnit(val);
String val2 = getSecond().value(el);
if (val2 == null)
return false;
ValueWithUnit ourVal = new ValueWithUnit(val2);
if (!result.isValid() || !ourVal.isValid())
return false;
int inter = result.compareTo(ourVal);
return doesCompare(inter);
}
public String toString() {
return "(" + first + getType().toSymbol() + getSecond() + ')';
}
}