/**
* 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 org.apache.drill.exec.record;
import io.netty.buffer.ByteBuf;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.apache.drill.common.expression.SchemaPath;
import org.apache.drill.exec.exception.SchemaChangeException;
import org.apache.drill.exec.expr.TypeHelper;
import org.apache.drill.exec.memory.BufferAllocator;
import org.apache.drill.exec.proto.SchemaDefProtos.FieldDef;
import org.apache.drill.exec.proto.UserBitShared.FieldMetadata;
import org.apache.drill.exec.proto.UserBitShared.RecordBatchDef;
import org.apache.drill.exec.vector.ValueVector;
import com.google.common.collect.Maps;
public class RecordBatchLoader implements Iterable<VectorWrapper<?>>{
static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(RecordBatchLoader.class);
private VectorContainer container = new VectorContainer();
private final BufferAllocator allocator;
private int valueCount;
private BatchSchema schema;
public RecordBatchLoader(BufferAllocator allocator) {
super();
this.allocator = allocator;
}
/**
* Load a record batch from a single buffer.
*
* @param def
* The definition for the record batch.
* @param buf
* The buffer that holds the data associated with the record batch
* @return Whether or not the schema changed since the previous load.
* @throws SchemaChangeException
*/
public boolean load(RecordBatchDef def, ByteBuf buf) throws SchemaChangeException {
// logger.debug("Loading record batch with def {} and data {}", def, buf);
this.valueCount = def.getRecordCount();
boolean schemaChanged = schema == null;
Map<MaterializedField, ValueVector> oldFields = Maps.newHashMap();
for(VectorWrapper<?> w : container){
ValueVector v = w.getValueVector();
oldFields.put(v.getField(), v);
}
VectorContainer newVectors = new VectorContainer();
List<FieldMetadata> fields = def.getFieldList();
int bufOffset = 0;
for (FieldMetadata fmd : fields) {
FieldDef fieldDef = fmd.getDef();
ValueVector v = oldFields.remove(fieldDef);
if(v != null){
container.add(v);
continue;
}
// if we arrive here, we didn't have a matching vector.
schemaChanged = true;
MaterializedField m = new MaterializedField(fieldDef);
v = TypeHelper.getNewVector(m, allocator);
if (fmd.getValueCount() == 0){
v.clear();
} else {
v.load(fmd, buf.slice(bufOffset, fmd.getBufferLength()));
}
bufOffset += fmd.getBufferLength();
newVectors.add(v);
}
if(!oldFields.isEmpty()){
schemaChanged = true;
for(ValueVector v : oldFields.values()){
v.close();
}
}
// rebuild the schema.
SchemaBuilder b = BatchSchema.newBuilder();
for(VectorWrapper<?> v : newVectors){
b.addField(v.getField());
}
b.setSelectionVectorMode(BatchSchema.SelectionVectorMode.NONE);
this.schema = b.build();
newVectors.buildSchema(BatchSchema.SelectionVectorMode.NONE);
container = newVectors;
return schemaChanged;
}
public TypedFieldId getValueVectorId(SchemaPath path) {
return container.getValueVector(path);
}
//
// @SuppressWarnings("unchecked")
// public <T extends ValueVector> T getValueVector(int fieldId, Class<?> clazz) {
// ValueVector v = container.get(fieldId);
// assert v != null;
// if (v.getClass() != clazz){
// logger.warn(String.format(
// "Failure while reading vector. Expected vector class of %s but was holding vector class %s.",
// clazz.getCanonicalName(), v.getClass().getCanonicalName()));
// return null;
// }
// return (T) v;
// }
public int getRecordCount() {
return valueCount;
}
public VectorWrapper<?> getValueAccessorById(int fieldId, Class<?> clazz){
return container.getValueAccessorById(fieldId, clazz);
}
public WritableBatch getWritableBatch(){
return WritableBatch.getBatchNoSVWrap(valueCount, container);
}
@Override
public Iterator<VectorWrapper<?>> iterator() {
return this.container.iterator();
}
public BatchSchema getSchema(){
return schema;
}
}