/*****************************************************************************
SQLJEP - Java SQL Expression Parser 0.2
November 1 2006
(c) Copyright 2006, Alexey Gaidukov
SQLJEP Author: Alexey Gaidukov
SQLJEP is based on JEP 2.24 (http://www.singularsys.com/jep/)
(c) Copyright 2002, Nathan Funk
See LICENSE.txt for license information.
*****************************************************************************/
package com.meidusa.amoeba.sqljep.function;
import java.sql.Time;
import com.meidusa.amoeba.sqljep.function.PostfixCommand;
import com.meidusa.amoeba.sqljep.ASTFunNode;
import com.meidusa.amoeba.sqljep.JepRuntime;
import com.meidusa.amoeba.sqljep.ParseException;
public class Datediff extends PostfixCommand {
final public int getNumberOfParameters() {
return 2;
}
/**
* Calculates the result of applying the "+" operator to the arguments from
* the stack and pushes it back on the stack.
*/
public Comparable<?>[] evaluate(ASTFunNode node, JepRuntime runtime) throws ParseException {
node.childrenAccept(runtime.ev, null);
Comparable<?> param2 = runtime.stack.pop();
Comparable<?> param1 = runtime.stack.pop();
return new Comparable<?>[]{param1,param2};
}
public static Long datediff(Comparable<?> param1, Comparable<?> param2) throws ParseException {
if (param1 == null && param2 == null) {
return null;
}
try {
if (param1 instanceof java.util.Date && param2 instanceof java.util.Date) {
if (param1 instanceof Time || param2 instanceof Time) {
throw new ParseException();
}
java.util.Date d1 = (java.util.Date)param1;
java.util.Date d2 = (java.util.Date)param2;
return new Long((d1.getTime()-d2.getTime())/86400000);
} else {
throw new ParseException();
}
} catch (ParseException e) {
throw new ParseException(WRONG_TYPE+" ("+param1.getClass()+"+"+param2.getClass()+")");
}
}
public Comparable<?> getResult(Comparable<?>... comparables)
throws ParseException {
Comparable<?> param2 = comparables[1];
Comparable<?> param1 = comparables[0];
return (datediff(param1, param2));
}
}