/*****************************************************************************
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.math.BigDecimal;
import java.sql.Timestamp;
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 final class Add extends PostfixCommand {
final static String DATE_ADDITION = "Wrong operation";
final static BigDecimal DAY_MILIS = new BigDecimal(86400000);
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 Comparable<?> add(Comparable<?> param1, Comparable<?> param2) throws ParseException {
if (param1 == null || param2 == null) {
return null;
}
if (param1 instanceof String) {
param1 = parse((String)param1);
}
if (param2 instanceof String) {
param2 = parse((String)param2);
}
if (param1 instanceof Number && param2 instanceof Number) {
// BigInteger type is not supported
Number n1 = (Number)param1;
Number n2 = (Number)param2;
if (n1 instanceof BigDecimal || n2 instanceof BigDecimal) {
BigDecimal b1 = getBigDecimal(n1);
BigDecimal b2 = getBigDecimal(n2);
return b1.add(b2);
}
if (n1 instanceof Double || n2 instanceof Double || n1 instanceof Float || n2 instanceof Float) {
return n1.doubleValue() + n2.doubleValue();
} else { // Long, Integer, Short, Byte
long l1 = n1.longValue();
long l2 = n2.longValue();
long r = l1 + l2;
if (l1 <= r && l2 <= r) { // overflow check
return r;
} else {
BigDecimal b1 = new BigDecimal(l1);
BigDecimal b2 = new BigDecimal(l2);
return b1.add(b2);
}
}
}
else if (param1 instanceof Timestamp || param2 instanceof Timestamp) {
if (param1 instanceof Timestamp && param2 instanceof Timestamp) {
throw new ParseException(DATE_ADDITION);
}
Timestamp d;
Number n;
if (param1 instanceof Timestamp) {
d = (Timestamp)param1;
if (param2 instanceof Number) {
n = (Number)param2;
} else {
throw new ParseException(DATE_ADDITION);
}
return new Timestamp(d.getTime()+toDay(n));
}
else if (param2 instanceof Timestamp) {
d = (Timestamp)param2;
if (param1 instanceof Number) {
n = (Number)param1;
} else {
throw new ParseException(DATE_ADDITION);
}
return new Timestamp(d.getTime()+toDay(n));
}
throw new ParseException(INTERNAL_ERROR);
} else {
throw new ParseException(WRONG_TYPE+" ("+param1.getClass()+"+"+param2.getClass()+")");
}
}
static long toDay(Number n) {
if (n instanceof BigDecimal) { // BigInteger is not supported
BigDecimal dec = (BigDecimal)n;
BigDecimal t = dec.multiply(DAY_MILIS);
t = t.setScale(0, BigDecimal.ROUND_HALF_UP);
return t.longValue();
} else { // Long, Integer, Short, Byte
return n.longValue()*86400000;
}
}
public Comparable<?> getResult(Comparable<?>... comparables)
throws ParseException {
return add(comparables[0], comparables[1]);
}
}