/*
* @(#)$Id: TextConstructor.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.constructor;
import xbird.xquery.XQueryException;
import xbird.xquery.dm.XQEventReceiver;
import xbird.xquery.dm.instance.XQueryDataModel;
import xbird.xquery.dm.value.Item;
import xbird.xquery.dm.value.Sequence;
import xbird.xquery.dm.value.node.DMText;
import xbird.xquery.expr.*;
import xbird.xquery.meta.*;
import xbird.xquery.parser.XQueryParserVisitor;
import xbird.xquery.type.node.NodeType;
/**
*
* <DIV lang="en"></DIV>
* <DIV lang="ja"></DIV>
*
* @author Makoto YUI (yuin405+xbird@gmail.com)
* @link http://www.w3.org/TR/xquery/#id-textConstructors
* @link http://www.w3.org/TR/xquery-semantics/#sec_textConstructors
*/
public final class TextConstructor extends AbstractXQExpression implements NodeConstructor {
private static final long serialVersionUID = -4141307426495140505L;
private final String _content;
private XQExpression _contentExpr;
public TextConstructor(XQExpression content) {
this._content = getValued(content);
this._contentExpr = content;
this._type = NodeType.TEXT;
}
public XQExpression visit(XQueryParserVisitor visitor, XQueryContext ctxt)
throws XQueryException {
return visitor.visit(this, ctxt);
}
public XQExpression getContent() {
return this._contentExpr;
}
public XQExpression staticAnalysis(StaticContext statEnv) throws XQueryException {
if(!_analyzed) {
this._analyzed = true;
if(_content == null) {
XQExpression analyzed = _contentExpr.staticAnalysis(statEnv);
if(analyzed instanceof Evaluable) {
return analyzed;
}
this._contentExpr = analyzed;
}
}
return this;
}
public Sequence<? extends Item> eval(Sequence<? extends Item> contextSeq, DynamicContext dynEnv)
throws XQueryException {
String instContent = _content;
if(instContent == null) {
instContent = processContentExpr(contextSeq, dynEnv);
}
if(instContent.length() == 0) {
return DMText.EMPTY_SEQ.clone();
} else {
return XQueryDataModel.createText(instContent);
}
}
@Override
public void evalAsEvents(XQEventReceiver handler, Sequence<? extends Item> contextSeq, DynamicContext dynEnv)
throws XQueryException {
String instContent = _content;
if(instContent == null) {
instContent = processContentExpr(contextSeq, dynEnv);
}
if(instContent.length() > 0) {
handler.evText(instContent);
}
}
private String processContentExpr(Sequence contextSeq, DynamicContext dynEnv)
throws XQueryException {
final Sequence src = _contentExpr.eval(contextSeq, dynEnv);
final Sequence<? extends Item> textSeq = src.atomize(dynEnv);
final IFocus<? extends Item> itor = textSeq.iterator();
if(!itor.hasNext()) {
itor.closeQuietly();
return "";
}
final StringBuilder buf = new StringBuilder(255);
while(true) {
final Item it = itor.next();
buf.append(it.stringValue());
if(itor.hasNext()) {
buf.append(' ');
} else {
break;
}
}
itor.closeQuietly();
return buf.toString();
}
}