/*
* @(#)$Id: ExtensionExpr.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.decorative;
import java.util.LinkedList;
import java.util.List;
import xbird.xquery.Pragma;
import xbird.xquery.XQueryException;
import xbird.xquery.dm.value.Item;
import xbird.xquery.dm.value.Sequence;
import xbird.xquery.expr.AbstractXQExpression;
import xbird.xquery.expr.XQExpression;
import xbird.xquery.expr.ext.BDQExpr;
import xbird.xquery.expr.ext.MapExpr;
import xbird.xquery.expr.flwr.Binding;
import xbird.xquery.expr.flwr.FLWRExpr;
import xbird.xquery.expr.flwr.ForClause;
import xbird.xquery.expr.func.DirectFunctionCall;
import xbird.xquery.expr.path.PathExpr;
import xbird.xquery.expr.var.BindingVariable;
import xbird.xquery.expr.var.VarRef;
import xbird.xquery.expr.var.BindingVariable.ForVariable;
import xbird.xquery.func.doc.FnCollection;
import xbird.xquery.meta.DynamicContext;
import xbird.xquery.meta.StaticContext;
import xbird.xquery.meta.XQueryContext;
import xbird.xquery.parser.XQueryParserVisitor;
/**
*
* <DIV lang="en"></DIV>
* <DIV lang="ja"></DIV>
*
* @author Makoto YUI (yuin405+xbird@gmail.com)
*/
public final class ExtensionExpr extends AbstractXQExpression implements DecorativeExpression {
private static final long serialVersionUID = 7078273458388928255L;
private final List<Pragma> pragmas;
private final XQExpression expr;
public ExtensionExpr(XQExpression expr, Pragma pragma) {
this(expr, new LinkedList<Pragma>());
pragmas.add(pragma);
}
public ExtensionExpr(XQExpression expr, List<Pragma> pragmas) {
this.expr = expr;
this.pragmas = pragmas;
}
public XQExpression visit(XQueryParserVisitor visitor, XQueryContext ctxt)
throws XQueryException {
return visitor.visit(this, ctxt);
}
public XQExpression getExpr() {
return this.expr;
}
public List<Pragma> getPragmas() {
return this.pragmas;
}
public void addPragma(Pragma pragma) {
pragmas.add(pragma);
}
public XQExpression staticAnalysis(StaticContext statEnv) throws XQueryException {
assert (!_analyzed);
if(!pragmas.isEmpty()) {
if(expr instanceof BDQExpr) {
for(Pragma p : pragmas) {
if("parallel".equals(p.getName().getLocalPart())) {
((BDQExpr) expr).setParallel(true);
return expr.staticAnalysis(statEnv);
}
}
} else if(expr instanceof FLWRExpr) {
FLWRExpr flwrExpr = ((FLWRExpr) expr);
List<Binding> clauses = flwrExpr.getClauses();
if(!clauses.isEmpty()) {
Binding firstClause = clauses.get(0);
BindingVariable bindingVar = firstClause.getVariable();
XQExpression bindingExpr = bindingVar.getValue();
if(bindingExpr instanceof DirectFunctionCall) {
DirectFunctionCall funcall = (DirectFunctionCall) bindingExpr;
if(FnCollection.FUNC_NAME.equals(funcall.getFuncName())) {
List<XQExpression> params = funcall.getParams();
final String colpath;
if(params.isEmpty()) {
colpath = "/";
} else {
XQExpression argExpr = params.get(0);
colpath = argExpr.eval(null, DynamicContext.DUMMY).toString();
}
MapExpr mapExpr = new MapExpr(colpath, bindingVar, flwrExpr);
return mapExpr.staticAnalysis(statEnv);
}
}
}
} else if(expr instanceof PathExpr) {
PathExpr pathExpr = (PathExpr) expr;
List<XQExpression> steps = pathExpr.getSteps();
if(steps.size() > 1) {
XQExpression firstStep = steps.get(0);
if(firstStep instanceof DirectFunctionCall) {
DirectFunctionCall funcall = (DirectFunctionCall) firstStep;
if(FnCollection.FUNC_NAME.equals(funcall.getFuncName())) {
List<XQExpression> params = funcall.getParams();
final String colpath;
if(params.isEmpty()) {
colpath = "/";
} else {
XQExpression argExpr = params.get(0);
colpath = argExpr.eval(null, DynamicContext.DUMMY).toString();
}
FLWRExpr newFlwr = new FLWRExpr();
ForVariable forVar = new ForVariable();
forVar.setValue(funcall);
newFlwr.addClause(new ForClause(forVar));
VarRef varref = new VarRef(forVar);
steps.set(0, varref);
newFlwr.setFilteredReturnExpr(pathExpr);
MapExpr mapExpr = new MapExpr(colpath, forVar, newFlwr);
return mapExpr.staticAnalysis(statEnv);
}
}
}
}
}
return expr.staticAnalysis(statEnv);
}
public Sequence<? extends Item> eval(Sequence<? extends Item> contextSeq, DynamicContext dynEnv)
throws XQueryException {
throw new IllegalStateException("ExtensionExpr should be pruned.");
}
}