/*
* @(#)$Id: CastingFunction.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.func.constructor;
import java.util.Iterator;
import xbird.xquery.XQRTException;
import xbird.xquery.XQueryException;
import xbird.xquery.dm.value.*;
import xbird.xquery.dm.value.sequence.ValueSequence;
import xbird.xquery.func.BuiltInFunction;
import xbird.xquery.func.FunctionSignature;
import xbird.xquery.meta.DynamicContext;
import xbird.xquery.misc.QNameTable.QualifiedName;
import xbird.xquery.type.*;
import xbird.xquery.type.xs.QNameType;
import xbird.xquery.type.xs.StringType;
/**
*
* <DIV lang="en"></DIV>
* <DIV lang="ja"></DIV>
*
* @author Makoto YUI (yuin405+xbird@gmail.com)
* @link http://www.w3.org/TR/xquery-operators/#casting
*/
public class CastingFunction extends BuiltInFunction {
private static final long serialVersionUID = -5912574732355599110L;
public static final String CLAZZ = CastingFunction.class.getName();
public CastingFunction(String funcName) {
super(funcName, obtainType(funcName));
}
protected CastingFunction(String funcName, Type retType) {
super(funcName, retType);
}
public CastingFunction() {
super();
}
public void initialize(String funcName) {
QualifiedName resolvedName = resolve(funcName);
this._funcName = resolvedName;
Type type = obtainType(funcName);
this._returnType = type;
final FunctionSignature[] sig = new FunctionSignature[1];
sig[0] = new FunctionSignature(resolvedName, new Type[] { TypeRegistry.safeGet("xs:anyAtomicType?") });
this._signs = sig;
}
private static Type obtainType(String baseName) {
String typeName = baseName + '?';
Type type = TypeRegistry.safeGet(typeName);
if(type == null) {
Type baseType = TypeRegistry.safeGet(baseName);
if(baseType == null) {
throw new XQRTException("err:XPST0051", "Type not found: " + type);
}
assert (baseType instanceof ItemType);
type = new SequenceType((ItemType) baseType, Type.Occurrence.OCC_ZERO_OR_ONE);
}
return type;
}
protected FunctionSignature[] signatures() {
final FunctionSignature[] s = new FunctionSignature[1];
s[0] = new FunctionSignature(getName(), new Type[] { TypeRegistry.safeGet("xs:anyAtomicType?") });
return s;
}
public Sequence eval(Sequence<? extends Item> contextSeq, ValueSequence argv, DynamicContext dynEnv)
throws XQueryException {
if(argv == null) {
throw new IllegalStateException();
}
final Item arg = argv.getItem(0);
final Iterator<? extends Item> argItor = arg.iterator();
if(!argItor.hasNext()) {
return ValueSequence.EMPTY_SEQUENCE;
}
final AtomicValue tocast = (AtomicValue) argItor.next();
final Type retType = getReturnType().prime();
final AtomicType casttoType = (AtomicType) retType;
final AtomicValue converted = tocast.castAs(casttoType, dynEnv);
return converted;
}
/**
* xs:QName($arg as xs:string) as xs:QName.
*/
public static final class XsQName extends CastingFunction {
private static final long serialVersionUID = -6928355100709355013L;
public static final String SYMBOL = "xs:QName";
public XsQName() {
super(SYMBOL, QNameType.QNAME);
}
@Override
protected FunctionSignature[] signatures() {
final FunctionSignature[] s = new FunctionSignature[1];
s[0] = new FunctionSignature(getName(), new Type[] { StringType.STRING });
return s;
}
}
}