org.apache.hadoop.hive.serde2.columnar.ColumnarStruct Maven / Gradle / Ivy
/**
* 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.hadoop.hive.serde2.columnar;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hive.serde2.lazy.ByteArrayRef;
import org.apache.hadoop.hive.serde2.lazy.LazyFactory;
import org.apache.hadoop.hive.serde2.lazy.LazyObjectBase;
import org.apache.hadoop.hive.serde2.lazy.LazyUtils;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.io.Text;
/**
* ColumnarStruct is different from LazyStruct in that ColumnarStruct's field
* Object get parsed at its initialize time when call
* {@link #init(BytesRefArrayWritable cols)}, while LazyStruct parse fields in a
* lazy way.
*
*/
public class ColumnarStruct extends ColumnarStructBase {
private static final Log LOG = LogFactory.getLog(ColumnarStruct.class);
Text nullSequence;
int lengthNullSequence;
/**
* Construct a ColumnarStruct object with the TypeInfo. It creates the first
* level object at the first place
*
* @param oi
* the ObjectInspector representing the type of this LazyStruct.
* @param notSkippedColumnIDs
* the column ids that should not be skipped
*/
public ColumnarStruct(ObjectInspector oi, List notSkippedColumnIDs, Text nullSequence) {
super(oi, notSkippedColumnIDs);
if (nullSequence != null) {
this.nullSequence = nullSequence;
this.lengthNullSequence = nullSequence.getLength();
}
}
@Override
protected int getLength(ObjectInspector objectInspector, ByteArrayRef cachedByteArrayRef,
int start, int fieldLen) {
if (fieldLen == lengthNullSequence) {
byte[] data = cachedByteArrayRef.getData();
if (LazyUtils.compare(data, start, fieldLen,
nullSequence.getBytes(), 0, lengthNullSequence) == 0) {
return -1;
}
}
return fieldLen;
}
@Override
protected LazyObjectBase createLazyObjectBase(ObjectInspector objectInspector) {
return LazyFactory.createLazyObject(objectInspector);
}
}