// 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.lazy;
import java.io.IOException;
import org.apache.hadoop.hive.serde2.io.ShortWritable;
import com.facebook.hive.orc.WriterImpl;
import com.facebook.hive.orc.lazy.OrcLazyObject.ValueNotPresentException;
class LazyShortDictionaryTreeReader extends LazyNumericDictionaryTreeReader {
LazyShortDictionaryTreeReader (int columnId, long rowIndexStride) {
super(columnId, rowIndexStride);
}
@Override
protected int getNumBytes() {
return WriterImpl.SHORT_BYTE_SIZE;
}
private short latestValue; //< Latest key that was read from reader.
/**
* Read an short value from the stream.
*/
private short readShort() throws IOException {
return latestValue = (short) readPrimitive();
}
private short latestValue() {
return latestValue;
}
ShortWritable createWritable(Object previous, short v) throws IOException {
ShortWritable result = null;
if (previous == null) {
result = new ShortWritable();
} else {
result = (ShortWritable) previous;
}
result.set(v);
return result;
}
@Override
public Object createWritableFromLatest(Object previous) throws IOException {
return createWritable(previous, latestValue());
}
/**
* Give the next short as a primitive
*/
@Override
public short nextShort(boolean readStream) throws IOException {
if (!readStream) {
return latestValue();
}
if (!valuePresent) {
throw new ValueNotPresentException("Cannot materialize short.");
}
return readShort();
}
@Override
public Object next(Object previous) throws IOException {
ShortWritable result = null;
if (valuePresent) {
result = createWritable(previous, readShort());
}
return result;
}
}