/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-2009 The eXist Project
* http://exist-db.org
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $Id$
*/
package org.exist.xquery.functions;
import org.exist.dom.QName;
import org.exist.xquery.Cardinality;
import org.exist.xquery.Dependency;
import org.exist.xquery.Function;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.Profiler;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.AtomicValue;
import org.exist.xquery.value.ComputableValue;
import org.exist.xquery.value.DoubleValue;
import org.exist.xquery.value.FunctionParameterSequenceType;
import org.exist.xquery.value.FunctionReturnSequenceType;
import org.exist.xquery.value.IntegerValue;
import org.exist.xquery.value.Item;
import org.exist.xquery.value.NumericValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceIterator;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.Type;
public class FunSum extends Function {
//Used to detect overflows : currently not used.
private boolean gotInfinity = false;
public final static FunctionSignature signatures[] = {
new FunctionSignature(
new QName("sum", Function.BUILTIN_FUNCTION_NS),
"Returns a value obtained by adding together the values in $arg. " +
"If $arg is the the empty sequence the xs:double value 0.0e0 is returned.",
new SequenceType[] {
new FunctionParameterSequenceType("arg", Type.ATOMIC, Cardinality.ZERO_OR_MORE, "The sequence of numbers to be summed up")},
new FunctionReturnSequenceType(Type.ATOMIC, Cardinality.EXACTLY_ONE, "the sum of all numbers in $arg")
),
new FunctionSignature(
new QName("sum", Function.BUILTIN_FUNCTION_NS),
"Returns a value obtained by adding together the values in $arg. " +
"If $arg is the the empty sequence then $default is returned.",
new SequenceType[] {
new FunctionParameterSequenceType("arg", Type.ATOMIC, Cardinality.ZERO_OR_MORE, "The sequence of numbers to be summed up"),
new FunctionParameterSequenceType("default", Type.ATOMIC, Cardinality.ZERO_OR_ONE, "The default value if $arg computes to the empty sequence")
},
new FunctionReturnSequenceType(Type.ATOMIC, Cardinality.EXACTLY_ONE, "the sum of all numbers in $arg")
)
};
public FunSum(XQueryContext context, FunctionSignature signature) {
super(context, signature);
}
public Sequence eval(Sequence contextSequence, Item contextItem) throws XPathException {
if (context.getProfiler().isEnabled()) {
context.getProfiler().start(this);
context.getProfiler().message(this, Profiler.DEPENDENCIES,
"DEPENDENCIES",
Dependency.getDependenciesName(this.getDependencies()));
if (contextSequence != null)
context.getProfiler().message(this, Profiler.START_SEQUENCES,
"CONTEXT SEQUENCE", contextSequence);
if (contextItem != null)
context.getProfiler().message(this, Profiler.START_SEQUENCES,
"CONTEXT ITEM", contextItem.toSequence());
}
Sequence result;
Sequence inner = getArgument(0).eval(contextSequence, contextItem);
if (inner.isEmpty()) {
//If $zero is not specified, then the value returned for an empty sequence is the xs:integer value 0
Sequence zero = IntegerValue.ZERO;
if(getSignature().getArgumentCount() == 2)
zero = getArgument(1).eval(contextSequence, contextItem);
result = zero;
} else {
SequenceIterator iter = inner.iterate();
Item item = iter.nextItem();
AtomicValue value = item.atomize();
//Any values of type xdt:untypedAtomic in the sequence $arg are cast to xs:double
if (value.getType() == Type.UNTYPED_ATOMIC)
value = value.convertTo(Type.DOUBLE);
if (!(value instanceof ComputableValue))
throw new XPathException(this, "XPTY0004: '" + Type.getTypeName(value.getType()) + "(" + value + ")' can not be an operand in a sum");
//Set the first value
ComputableValue sum = (ComputableValue) value;
while (iter.hasNext()) {
item = iter.nextItem();
value = item.atomize();
//Any values of type xdt:untypedAtomic in the sequence $arg are cast to xs:double
if (value.getType() == Type.UNTYPED_ATOMIC)
value = value.convertTo(Type.DOUBLE);
if (!(value instanceof ComputableValue))
throw new XPathException(this, "XPTY0004: '" + Type.getTypeName(value.getType()) + "(" + value + ")' can not be an operand in a sum");
if (Type.subTypeOf(value.getType(), Type.NUMBER)) {
if (((NumericValue)value).isInfinite())
gotInfinity = true;
if (((NumericValue)value).isNaN()) {
sum = DoubleValue.NaN;
break;
}
}
sum = (ComputableValue)sum.promote(value);
//Aggregate next values
sum = sum.plus((ComputableValue) value);
}
result = sum;
}
if (!gotInfinity) {
if (Type.subTypeOf(result.getItemType(), Type.NUMBER) && ((NumericValue)result).isInfinite()) {
//Throw an overflow eception here since we get an infinity
//whereas is hasn't been provided by the sequence
}
}
if (context.getProfiler().isEnabled())
context.getProfiler().end(this, "", result);
return result;
}
}