/*
* 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.store;
import static com.hp.hpl.jena.sdb.util.StrUtils.sqlList;
import static org.apache.jena.atlas.lib.StrUtils.strjoin ;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.hp.hpl.jena.graph.Node;
import com.hp.hpl.jena.sdb.core.sqlexpr.SqlConstant;
import com.hp.hpl.jena.sdb.shared.SDBInternalError;
import com.hp.hpl.jena.sdb.sql.RS;
import com.hp.hpl.jena.sdb.sql.ResultSetJDBC;
import com.hp.hpl.jena.sdb.sql.SDBConnection;
import com.hp.hpl.jena.sdb.sql.SDBExceptionSQL;
public abstract class TupleLoaderOne extends TupleLoaderBase
{
private static Logger log = LoggerFactory.getLogger(TupleLoaderOne.class);
public TupleLoaderOne(SDBConnection connection)
{
super(connection) ;
}
public TupleLoaderOne(SDBConnection connection, TableDesc tableDesc)
{ super(connection, tableDesc) ; }
@Override
public void start()
{ super.start() ; }
@Override
public void finish()
{ super.finish(); }
@Override
public void load(Node... row)
{
if ( row.length != getTableWidth() )
{
String fmt = "TupleLoaderOne(%s) Expected row length: %d but got %d" ;
String msg = String.format(fmt, getTableName(), getTableWidth(), row.length) ;
throw new SDBInternalError(msg) ;
}
// Process nodes.
String[] vals = prepareNodes(row) ;
// Load if not present.
if ( ! entryExists(vals) )
loadRow(vals) ;
}
protected String[] prepareNodes(Node[] row)
{
String[] vals = new String[getTableWidth()] ;
for ( int i = 0 ; i < getTableWidth() ; i++ )
{
vals[i] = ensureNode(row[i]).asSqlString() ;
}
return vals ;
}
protected boolean entryExists(String[] vals)
{
String rowValues = whereRow(vals) ;
String selectTemplate = "SELECT count(*) FROM %s WHERE %s\n" ;
String sqlStmt = String.format(selectTemplate, getTableName(), rowValues) ;
ResultSetJDBC rs = null ;
try {
rs = connection().execQuery(sqlStmt) ;
rs.get().next() ;
int count = rs.get().getInt(1) ;
if ( count > 0 )
{
log.debug("Duplicate tuple detected: count="+count+" :: "+vals) ;
return true;
}
// Otherwise deos not exist
return false ;
}
catch (SQLException ex)
{ throw new SDBExceptionSQL(ex) ; }
finally { RS.close(rs) ; }
}
protected void loadRow(String[] vals)
{
/*
INSERT INTO table
(column-1, column-2, ... column-n)
VALUES
(value-1, value-2, ... value-n);
*/
// String insertTemplate = "INSERT INTO %s\n (%s)\nVALUES\n (%s)" ;
// String colNameList = sqlList(getColumnNames()) ;
// String sqlStmt = String.format(insertTemplate, getTableName(), colNameList, sqlList(vals)) ;
// exec(sqlStmt) ;
String insertTemplate = "INSERT INTO %s VALUES\n (%s)" ;
String sqlStmt = String.format(insertTemplate, getTableName(), sqlList(vals)) ;
exec(sqlStmt) ;
}
@Override
public void unload(Node... row)
{
String[] vals = new String[getTableWidth()] ;
for ( int i = 0 ; i < getTableWidth() ; i++ )
vals[i] = refNode(row[i]).asSqlString() ;
String rowValues = whereRow(vals) ;
String deleteTemplate = "DELETE FROM %s WHERE %s" ;
String sqlStmt = String.format(deleteTemplate, getTableName(), rowValues) ;
exec(sqlStmt) ;
}
protected void exec(String sqlStmt)
{
try
{ connection().exec(sqlStmt) ; }
catch (SQLException ex)
{ throw new SDBExceptionSQL(ex) ; }
}
private SqlConstant ensureNode(Node node)
{
try {
return insertNode(node) ;
} catch (SQLException ex){
throw new SDBExceptionSQL("PatternTableLoader.prepareNode", ex) ;
}
}
private SqlConstant refNode(Node node)
{
try {
return getRefForNode(node) ;
} catch (SQLException ex){
throw new SDBExceptionSQL("PatternTableLoader.getRefForNode", ex) ;
}
}
private String whereRow(String[] vals)
{
List<String> rowValues = new ArrayList<String>(getTableWidth()) ;
for ( int i = 0 ; i < getTableWidth() ; i++ )
{
String x = getTableDesc().getColNames().get(i)+"="+vals[i] ;
rowValues.add(x) ;
}
return strjoin(" AND ", rowValues) ;
}
abstract public SqlConstant getRefForNode(Node node) throws SQLException ;
abstract public SqlConstant insertNode(Node node) throws SQLException ;
}