/*
* @(#)$Id: CastableExpr.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.types;
import xbird.xquery.StaticError;
import xbird.xquery.XQueryException;
import xbird.xquery.dm.value.*;
import xbird.xquery.dm.value.xsi.BooleanValue;
import xbird.xquery.expr.AbstractXQExpression;
import xbird.xquery.expr.XQExpression;
import xbird.xquery.meta.*;
import xbird.xquery.misc.TypeUtil;
import xbird.xquery.parser.XQueryParserVisitor;
import xbird.xquery.type.AtomicType;
import xbird.xquery.type.Type;
import xbird.xquery.type.xs.BooleanType;
import xbird.xquery.type.xs.NOTATIONType;
/**
*
* <DIV lang="en"></DIV>
* <DIV lang="ja"></DIV>
*
* @author Makoto YUI (yuin405+xbird@gmail.com)
* @link http://www.w3.org/TR/xquery/#doc-xquery-CastableExpr
* @link http://www.w3.org/TR/xquery/#doc-xquery-SingleType
*/
public class CastableExpr extends AbstractXQExpression {
private static final long serialVersionUID = 5090688169583974420L;
protected XQExpression _inputExpr;
protected final Type _targetType; /* restricted to SingleType */
public CastableExpr(XQExpression expr, Type type) {
this._inputExpr = expr;
this._targetType = type;
}
public XQExpression getExpression() {
return this._inputExpr;
}
public Type getTargetType() {
return this._targetType;
}
public XQExpression visit(XQueryParserVisitor visitor, XQueryContext ctxt)
throws XQueryException {
return visitor.visit(this, ctxt);
}
public XQExpression staticAnalysis(StaticContext statEnv) throws XQueryException {
if(!_analyzed) {
this._analyzed = true;
final Type primeType = _targetType.prime();
if(primeType == NOTATIONType.NOTATION || primeType == AtomicType.ANY_ATOMIC_TYPE) {
throw new StaticError("err:XPST0080", "Illegal target type: " + _targetType);
}
this._inputExpr = _inputExpr.staticAnalysis(statEnv);
this._type = BooleanType.BOOLEAN;
}
return this;
}
public Sequence<? extends Item> eval(Sequence<? extends Item> contextSeq, DynamicContext dynEnv)
throws XQueryException {
final Sequence<? extends Item> input = _inputExpr.eval(contextSeq, dynEnv).atomize(dynEnv);
final IFocus<? extends Item> itor = input.iterator();
if(itor.hasNext()) {
final Item it = itor.next();
if(itor.hasNext()) {
itor.closeQuietly();
return BooleanValue.FALSE;
}
itor.closeQuietly();
if(it instanceof AtomicValue) {
try {
final AtomicType tt = (AtomicType) _targetType.prime();
final AtomicValue casteed = ((AtomicValue) it).castAs(tt, dynEnv);
} catch (XQueryException e) {
return BooleanValue.FALSE;
}
return BooleanValue.TRUE;
} else {
return BooleanValue.FALSE;
}
} else {
itor.closeQuietly();
return TypeUtil.isOptional(_targetType) ? BooleanValue.TRUE : BooleanValue.FALSE;
}
}
}