com.facebook.hive.orc.lazy.LazyBooleanTreeReader.java Source code

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Here is the source code for com.facebook.hive.orc.lazy.LazyBooleanTreeReader.java

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//  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 java.util.List;
import java.util.Map;

import org.apache.hadoop.io.BooleanWritable;

import com.facebook.hive.orc.BitFieldReader;
import com.facebook.hive.orc.InStream;
import com.facebook.hive.orc.OrcProto;
import com.facebook.hive.orc.StreamName;
import com.facebook.hive.orc.OrcProto.RowIndex;
import com.facebook.hive.orc.OrcProto.RowIndexEntry;
import com.facebook.hive.orc.lazy.OrcLazyObject.ValueNotPresentException;

public class LazyBooleanTreeReader extends LazyTreeReader {

    private BitFieldReader reader = null;
    private boolean latestRead = true; //< Latest value from stream.

    public LazyBooleanTreeReader(int columnId, long rowIndexStride) {
        super(columnId, rowIndexStride);
    }

    @Override
    public void startStripe(Map<StreamName, InStream> streams, List<OrcProto.ColumnEncoding> encodings,
            RowIndex[] indexes, long rowBaseInStripe) throws IOException {
        super.startStripe(streams, encodings, indexes, rowBaseInStripe);
        reader = new BitFieldReader(streams.get(new StreamName(columnId, OrcProto.Stream.Kind.DATA)));
        if (indexes[columnId] != null) {
            loadIndeces(indexes[columnId].getEntryList(), 0);
        }
    }

    @Override
    public void seek(int index) throws IOException {
        reader.seek(index);
    }

    @Override
    public int loadIndeces(List<RowIndexEntry> rowIndexEntries, int startIndex) {
        int updatedStartIndex = super.loadIndeces(rowIndexEntries, startIndex);
        return reader.loadIndeces(rowIndexEntries, updatedStartIndex);
    }

    @Override
    public void skipRows(long numNonNullValues) throws IOException {
        reader.skip(numNonNullValues);
    }

    boolean readBoolean() throws IOException {
        latestRead = (reader.next() == 1);
        return latestRead;
    }

    BooleanWritable createWritable(Object previous, boolean v) throws IOException {
        BooleanWritable result = null;
        if (previous == null) {
            result = new BooleanWritable();
        } else {
            result = (BooleanWritable) previous;
        }
        result.set(v);
        return result;
    }

    @Override
    public Object createWritableFromLatest(Object previous) throws IOException {
        return createWritable(previous, latestRead);
    }

    @Override
    public boolean nextBoolean(boolean readStream) throws IOException {
        if (!readStream) {
            return latestRead;
        }
        if (!valuePresent) {
            throw new ValueNotPresentException("Cannot materialize boolean.");
        }
        return readBoolean();

    }

    @Override
    public Object next(Object previous) throws IOException {
        BooleanWritable result = null;
        if (valuePresent) {
            result = createWritable(previous, readBoolean());
        }
        return result;
    }

    @Override
    public void close() throws IOException {
        super.close();
        if (reader != null) {
            reader.close();
        }
    }
}