/*
* @(#)$Id: RangeExpr.java 3619 2008-03-26 07:23:03Z yui $
*
* Copyright 2006-2008 Makoto YUI
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* Contributors:
* Makoto YUI - initial implementation
*/
package xbird.xquery.expr.seq;
import xbird.xquery.TypeError;
import xbird.xquery.XQueryException;
import xbird.xquery.dm.value.Item;
import xbird.xquery.dm.value.Sequence;
import xbird.xquery.dm.value.literal.XInteger;
import xbird.xquery.dm.value.sequence.ValueSequence;
import xbird.xquery.expr.XQExpression;
import xbird.xquery.meta.*;
import xbird.xquery.misc.TypeUtil;
import xbird.xquery.parser.XQueryParserVisitor;
import xbird.xquery.type.Type;
import xbird.xquery.type.TypeRegistry;
/**
*
* <DIV lang="en">
* fs:to($firstval as xs:integer?, $lastval as xs:integer?) as xs:integer*.
* </DIV>
* <DIV lang="ja"></DIV>
*
* @author Makoto YUI (yuin405+xbird@gmail.com)
* @link http://www.w3.org/TR/xquery-semantics/#sec_fs_to
*/
public final class RangeExpr extends SequenceOp {
private static final long serialVersionUID = 8826678173081694777L;
public RangeExpr(XQExpression leftOperand, XQExpression rightOperand) {
super(leftOperand, rightOperand, TypeRegistry.safeGet("xs:integer*"));
}
public String getOperator() {
return "to";
}
@Override
public XQExpression visit(XQueryParserVisitor visitor, XQueryContext ctxt)
throws XQueryException {
return visitor.visit(this, ctxt);
}
@Override
public XQExpression staticAnalysis(StaticContext statEnv) throws XQueryException {
if(!_analyzed) {
this._analyzed = true;
this._leftOperand = _leftOperand.staticAnalysis(statEnv);
this._rightOperand = _rightOperand.staticAnalysis(statEnv);
final Type integerType = TypeRegistry.safeGet("xs:integer?");
if(!TypeUtil.subtypeOf(_leftOperand.getType(), integerType)) {
throw new TypeError("Inferred type of left operand is invalid: "
+ _leftOperand.getType());
}
if(!TypeUtil.subtypeOf(_rightOperand.getType(), integerType)) {
throw new TypeError("Inferred type of left operand is invalid: "
+ _rightOperand.getType());
}
}
return this;
}
public ValueSequence eval(Sequence<? extends Item> contextSeq, DynamicContext dynEnv)
throws XQueryException {
final Sequence<? extends Item> first = _leftOperand.eval(contextSeq, dynEnv);
final Sequence<? extends Item> second = _rightOperand.eval(contextSeq, dynEnv);
final IFocus<? extends Item> firstItor = first.iterator();
final IFocus<? extends Item> secondItor = second.iterator();
if(!firstItor.hasNext() || !secondItor.hasNext()) {
firstItor.closeQuietly();
secondItor.closeQuietly();
return ValueSequence.EMPTY_SEQUENCE;
}
final Item firstItem = firstItor.next();
final Item secondItem = secondItor.next();
assert (!firstItor.hasNext());
assert (!secondItor.hasNext());
firstItor.closeQuietly();
secondItor.closeQuietly();
final ValueSequence newSeq = new ValueSequence(dynEnv);
final int from = ((XInteger) firstItem).getNumber().intValue();
final int to = ((XInteger) secondItem).getNumber().intValue();
for(int i = from; i <= to; i++) {
newSeq.addItem(new XInteger(i));
}
return newSeq;
}
}