// PSP Dashboard - Data Automation Tool for PSP-like processes
// Copyright (C) 1999 United States Air Force
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// 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.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
// The author(s) may be contacted at:
// OO-ALC/TISHD
// Attn: PSP Dashboard Group
// 6137 Wardleigh Road
// Hill AFB, UT 84056-5843
//
// E-Mail POC: ken.raisor@hill.af.mil
package pspdash.data.compiler;
import pspdash.data.DataRepository;
import pspdash.data.SimpleData;
import pspdash.data.DoubleData;
import pspdash.data.ListData;
import java.util.List;
public class Nvl extends AbstractFunction {
/** Perform a procedure call.
*
* This method <b>must</b> be thread-safe.
*/
public Object call(List arguments, ExpressionContext context)
{
SimpleData arg;
for (int i = 0; i < arguments.size(); i++)
if (!isBadValue(arg = getArg(arguments, i)))
return arg;
return null;
}
private static boolean isBadValue(SimpleData data) {
// null values are "bad".
if (data == null) return true;
// numbers with non-real values are "bad".
if (data instanceof DoubleData) {
double d = ((DoubleData) data).getDouble();
if (Double.isNaN(d) || Double.isInfinite(d)) return true;
}
// everything else is "good".
return false;
}
}