/*
* Copyright (c) 2007-2014 Concurrent, Inc. All Rights Reserved.
*
* Project and contact information: http://www.cascading.org/
*
* This file is part of the Cascading project.
*
* 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.
*/
package cascading.lingual.optiq.enumerable;
import java.lang.reflect.Type;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;
import cascading.flow.FlowProcess;
import cascading.lingual.catalog.SchemaCatalogManager;
import cascading.lingual.catalog.TableDef;
import cascading.lingual.jdbc.Driver;
import cascading.lingual.optiq.meta.TableHolder;
import cascading.lingual.platform.PlatformBroker;
import cascading.lingual.util.Misc;
import cascading.lingual.util.Optiq;
import cascading.tap.SinkMode;
import cascading.tap.Tap;
import net.hydromatic.linq4j.AbstractEnumerable;
import net.hydromatic.linq4j.Enumerable;
import net.hydromatic.linq4j.Enumerator;
import net.hydromatic.optiq.rules.java.PhysType;
import org.eigenbase.relopt.volcano.VolcanoPlanner;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/** Enumerable that reads from a Cascading Tap. */
public class CascadingTapEnumerable extends AbstractEnumerable implements Enumerable
{
private static final Logger LOG = LoggerFactory.getLogger( CascadingTapEnumerable.class );
static long holdersCount = 0;
static final Map<Long, TableHolder> holders = new HashMap<Long, TableHolder>();
protected final TableHolder tableHolder;
public static synchronized long addHolder( TableHolder tableHolder )
{
long count = holdersCount++;
holders.put( count, tableHolder );
return count;
}
public static synchronized TableHolder popHolder( long index )
{
return holders.remove( index );
}
public CascadingTapEnumerable( long index )
{
tableHolder = popHolder( index );
}
public PhysType getPhysType()
{
return tableHolder.physType;
}
public TableDef getTableDef()
{
return tableHolder.tableDef;
}
public PlatformBroker getPlatformBroker()
{
return tableHolder.platformBroker;
}
public VolcanoPlanner getVolcanoPlanner()
{
return tableHolder.planner;
}
public Enumerator enumerator()
{
PlatformBroker platformBroker = getPlatformBroker();
Properties properties = platformBroker.getProperties();
Optiq.writeSQLPlan( properties, Misc.createUniqueName(), getVolcanoPlanner() );
FlowProcess flowProcess = platformBroker.getFlowProcess();
SchemaCatalogManager schemaCatalog = platformBroker.getCatalogManager();
Tap tap = schemaCatalog.createTapFor( getTableDef(), SinkMode.KEEP );
int size = tap.getSourceFields().size();
Type[] types = new Type[ size ];
for( int i = 0; i < size; i++ )
types[ i ] = getPhysType().fieldClass( i );
int maxRows = getMaxRows( properties );
if( size == 1 )
return new TapObjectEnumerator( maxRows, types, flowProcess, tap );
else
return new TapArrayEnumerator( maxRows, types, flowProcess, tap );
}
private int getMaxRows( Properties properties )
{
if( !properties.containsKey( Driver.MAX_ROWS ) )
return Integer.MAX_VALUE;
return Integer.parseInt( properties.getProperty( Driver.MAX_ROWS ) );
}
}