// Copyright (c) 2013, Facebook, Inc. All rights reserved.
/**
* 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.facebook.hive.orc;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Properties;
import org.apache.hadoop.conf.Configuration;
import com.facebook.hive.orc.lazy.OrcLazyRowObjectInspector;
import org.apache.hadoop.hive.serde2.SerDe;
import org.apache.hadoop.hive.serde2.SerDeException;
import org.apache.hadoop.hive.serde2.SerDeStats;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.typeinfo.StructTypeInfo;
import org.apache.hadoop.hive.serde2.typeinfo.TypeInfo;
import org.apache.hadoop.hive.serde2.typeinfo.TypeInfoUtils;
import org.apache.hadoop.io.Writable;
/**
* A serde class for ORC.
* It transparently passes the object to/from the ORC file reader/writer.
*/
public class OrcSerde implements SerDe {
private final OrcSerdeRow row = new OrcSerdeRow();
private ObjectInspector inspector = null;
final class OrcSerdeRow implements Writable {
private Object realRow;
private ObjectInspector inspector;
@Override
public void write(DataOutput dataOutput) throws IOException {
throw new UnsupportedOperationException("can't write the bundle");
}
@Override
public void readFields(DataInput dataInput) throws IOException {
throw new UnsupportedOperationException("can't read the bundle");
}
ObjectInspector getInspector() {
return inspector;
}
Object getRow() {
return realRow;
}
}
@Override
public void initialize(Configuration conf, Properties table) {
// Read the configuration parameters
String columnNameProperty = table.getProperty("columns");
// NOTE: if "columns.types" is missing, all columns will be of String type
String columnTypeProperty = table.getProperty("columns.types");
// Parse the configuration parameters
ArrayList<String> columnNames = new ArrayList<String>();
if (columnNameProperty != null && columnNameProperty.length() > 0) {
for(String name: columnNameProperty.split(",")) {
columnNames.add(name);
}
}
if (columnTypeProperty == null) {
// Default type: all string
StringBuilder sb = new StringBuilder();
for (int i = 0; i < columnNames.size(); i++) {
if (i > 0) {
sb.append(":");
}
sb.append("string");
}
columnTypeProperty = sb.toString();
}
ArrayList<TypeInfo> fieldTypes =
TypeInfoUtils.getTypeInfosFromTypeString(columnTypeProperty);
StructTypeInfo rootType = new StructTypeInfo();
rootType.setAllStructFieldNames(columnNames);
rootType.setAllStructFieldTypeInfos(fieldTypes);
inspector = new OrcLazyRowObjectInspector(rootType);
}
@Override
public Class<? extends Writable> getSerializedClass() {
return OrcSerdeRow.class;
}
@Override
public Writable serialize(Object realRow, ObjectInspector inspector) {
row.realRow = realRow;
row.inspector = inspector;
return row;
}
@Override
public Object deserialize(Writable writable) throws SerDeException {
return writable;
}
@Override
public ObjectInspector getObjectInspector() throws SerDeException {
return inspector;
}
/**
* Always returns null, since serialized size doesn't make sense in the
* context of ORC files.
* @return null
*/
@Override
public SerDeStats getSerDeStats() {
return null;
}
}