/**
* 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.hbase;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hive.serde2.lazy.ByteArrayRef;
import org.apache.hadoop.hive.serde2.lazy.LazyFactory;
import org.apache.hadoop.hive.serde2.lazy.LazyObject;
import org.apache.hadoop.hive.serde2.lazy.LazyStruct;
import org.apache.hadoop.hive.serde2.lazy.objectinspector.LazySimpleStructObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.StructField;
/**
* HBaseCompositeKey extension of LazyStruct. All complex composite keys should extend this class
* and override the {@link LazyStruct#getField(int)} method where fieldID corresponds to the ID of a
* key in the composite key.
* <p>
* For example, for a composite key <i>"/part1/part2/part3"</i>, <i>part1</i> will have an id
* <i>0</i>, <i>part2</i> will have an id <i>1</i> and <i>part3</i> will have an id <i>2</i>. Custom
* implementations of getField(fieldID) should return the value corresponding to that fieldID. So,
* for the above example, the value returned for <i>getField(0)</i> should be </i>part1</i>,
* <i>getField(1)</i> should be <i>part2</i> and <i>getField(2)</i> should be <i>part3</i>.
* </p>
*
* <p>
* All custom implementation are expected to have a constructor of the form:
*
* <pre>
* MyCustomCompositeKey(LazySimpleStructObjectInspector oi, Properties tbl, Configuration conf)
* </pre>
*
* </p>
*
* */
public class HBaseCompositeKey extends LazyStruct {
public HBaseCompositeKey(LazySimpleStructObjectInspector oi) {
super(oi);
}
@Override
public ArrayList<Object> getFieldsAsList() {
ArrayList<Object> allFields = new ArrayList<Object>();
List<? extends StructField> fields = oi.getAllStructFieldRefs();
for (int i = 0; i < fields.size(); i++) {
allFields.add(getField(i));
}
return allFields;
}
/**
* Create an initialize a {@link LazyObject} with the given bytes for the given fieldID.
*
* @param fieldID
* field for which the object is to be created
* @param bytes
* value with which the object is to be initialized with
* @return initialized {@link LazyObject}
* */
public LazyObject<? extends ObjectInspector> toLazyObject(int fieldID, byte[] bytes) {
ObjectInspector fieldOI = oi.getAllStructFieldRefs().get(fieldID).getFieldObjectInspector();
LazyObject<? extends ObjectInspector> lazyObject = LazyFactory
.createLazyObject(fieldOI);
ByteArrayRef ref = new ByteArrayRef();
ref.setData(bytes);
// initialize the lazy object
lazyObject.init(ref, 0, ref.getData().length);
return lazyObject;
}
}