/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
package com.hp.hpl.jena.sdb.layout1;
import java.sql.SQLException;
import java.util.List;
import com.hp.hpl.jena.graph.Node;
import com.hp.hpl.jena.sdb.core.SDBRequest;
import com.hp.hpl.jena.sdb.core.ScopeEntry;
import com.hp.hpl.jena.sdb.core.sqlexpr.SqlColumn;
import com.hp.hpl.jena.sdb.core.sqlnode.SqlNode;
import com.hp.hpl.jena.sdb.sql.ResultSetJDBC;
import com.hp.hpl.jena.sdb.sql.SQLUtils;
import com.hp.hpl.jena.sdb.store.SQLBridgeBase;
import com.hp.hpl.jena.sparql.core.Var;
import com.hp.hpl.jena.sparql.engine.binding.Binding;
import com.hp.hpl.jena.sparql.engine.binding.BindingFactory ;
import com.hp.hpl.jena.sparql.engine.binding.BindingMap;
public class SQLBridge1 extends SQLBridgeBase
{
private EncoderDecoder codec ;
public SQLBridge1(SDBRequest request, SqlNode sqlNode, List<Var> projectVars, EncoderDecoder codec)
{
super(request, sqlNode, projectVars) ;
this.codec = codec ;
}
@Override
protected void buildValues()
{
// No added SQL operations to get the values.
// If it is a SelectBlock for renaming purposes, strip the
// renames out as they are unnecessary. Affects scopes.
if ( getSqlNode().isSelectBlock() )
setSqlNode(getSqlNode().asSelectBlock().clearView()) ;
}
@Override
protected void buildProject()
{
for ( Var v : getProject() )
{
if ( ! v.isNamedVar() )
continue ;
// Value scope == IdScope for layout1
// CHECK
ScopeEntry e = getSqlExprNode().getIdScope().findScopeForVar(v) ;
if ( e == null )
continue ;
SqlColumn c = e.getColumn() ;
String sqlVarName = allocSqlName(v) ;
addProject(c, sqlVarName) ;
addAnnotation(sqlVarName+"="+v.toString()) ;
}
setAnnotation() ;
}
@Override
protected Binding assembleBinding(ResultSetJDBC rs, Binding parent)
{
BindingMap b = BindingFactory.create(parent) ;
for ( Var v : getProject() )
{
String sqlVarName = getSqlName(v) ;
if ( sqlVarName == null )
// Not mentioned in query.
continue ;
try {
// because of encoding into SPARQL terms, this is never the empty string.
String s = rs.get().getString(sqlVarName) ;
// Same as rs.wasNull() for things that can return Java nulls.
if ( s == null )
continue ;
// TupleLoaderSimple used SqlConstant which made the string SQL-safe
// so it could be embedded in a non-prepared statement.
s = SQLUtils.unescapeStr(s) ;
Node n = codec.decode(s) ;
b.add(v, n) ;
// Ignore any access error (variable requested not in results)
} catch (SQLException ex) {}
}
return b ;
}
}