com.linkedin.pinot.core.index.writer.impl.FixedBitWidthSingleColumnMultiValueWriter.java Source code

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Here is the source code for com.linkedin.pinot.core.index.writer.impl.FixedBitWidthSingleColumnMultiValueWriter.java

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/**
 * Copyright (C) 2014-2015 LinkedIn Corp. (pinot-core@linkedin.com)
 *
 * Licensed 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.linkedin.pinot.core.index.writer.impl;

import com.linkedin.pinot.common.utils.MmapUtils;
import java.io.File;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;

import com.linkedin.pinot.core.index.reader.DataFileMetadata;
import com.linkedin.pinot.core.index.reader.impl.FixedByteWidthRowColDataFileReader;
import com.linkedin.pinot.core.index.writer.SingleColumnMultiValueWriter;
import org.apache.commons.io.IOUtils;

public class FixedBitWidthSingleColumnMultiValueWriter implements SingleColumnMultiValueWriter {
    private static int SIZE_OF_INT = 4;
    private static int NUM_COLS_IN_HEADER = 2;
    private ByteBuffer headerBuffer;
    private ByteBuffer dataBuffer;
    private RandomAccessFile raf;
    private FixedByteWidthRowColDataFileWriter headerWriter;
    private FixedBitWidthRowColDataFileWriter dataWriter;
    private FixedByteWidthRowColDataFileReader headerReader;

    public FixedBitWidthSingleColumnMultiValueWriter(File file, int numDocs, int totalNumValues,
            int columnSizeInBits) throws Exception {
        // there will be two sections header and data
        // header will contain N lines, each line corresponding to the
        int headerSize = numDocs * SIZE_OF_INT * NUM_COLS_IN_HEADER;
        int dataSize = (totalNumValues * columnSizeInBits + 7) / 8;
        int totalSize = headerSize + dataSize;
        raf = new RandomAccessFile(file, "rw");
        headerBuffer = MmapUtils.mmapFile(raf, FileChannel.MapMode.READ_WRITE, 0, headerSize, file,
                this.getClass().getSimpleName() + " headerBuffer");
        dataBuffer = MmapUtils.mmapFile(raf, FileChannel.MapMode.READ_WRITE, headerSize, dataSize, file,
                this.getClass().getSimpleName() + " dataBuffer");
        headerWriter = new FixedByteWidthRowColDataFileWriter(headerBuffer, numDocs, 2,
                new int[] { SIZE_OF_INT, SIZE_OF_INT });
        headerReader = new FixedByteWidthRowColDataFileReader(headerBuffer, numDocs, 2,
                new int[] { SIZE_OF_INT, SIZE_OF_INT });

        dataWriter = new FixedBitWidthRowColDataFileWriter(dataBuffer, totalNumValues, 1,
                new int[] { columnSizeInBits });

    }

    @Override
    public boolean setMetadata(DataFileMetadata metadata) {
        // TODO Auto-generated method stub
        return false;
    }

    @Override
    public void close() {
        IOUtils.closeQuietly(raf);
        raf = null;
        MmapUtils.unloadByteBuffer(dataBuffer);
        MmapUtils.unloadByteBuffer(headerBuffer);
    }

    private int updateHeader(int row, int length) {
        int prevRowStartIndex = 0;
        int prevRowLength = 0;
        if (row > 0) {
            prevRowStartIndex = headerReader.getInt(row - 1, 0);
            prevRowLength = headerReader.getInt(row - 1, 1);
        }
        int newStartIndex = prevRowStartIndex + prevRowLength;
        headerWriter.setInt(row, 0, newStartIndex);
        headerWriter.setInt(row, 1, length);
        return newStartIndex;
    }

    @Override
    public void setCharArray(int row, char[] charArray) {
        throw new UnsupportedOperationException("Only int data type is supported in fixedbit format");

    }

    @Override
    public void setShortArray(int row, short[] shortsArray) {
        throw new UnsupportedOperationException("Only int data type is supported in fixedbit format");

    }

    @Override
    public void setIntArray(int row, int[] intArray) {
        int newStartIndex = updateHeader(row, intArray.length);
        for (int i = 0; i < intArray.length; i++) {
            dataWriter.setInt(newStartIndex + i, 0, intArray[i]);
        }
    }

    @Override
    public void setLongArray(int row, long[] longArray) {
        throw new UnsupportedOperationException("Only int data type is supported in fixedbit format");

    }

    @Override
    public void setFloatArray(int row, float[] floatArray) {
        throw new UnsupportedOperationException("Only int data type is supported in fixedbit format");

    }

    @Override
    public void setDoubleArray(int row, double[] doubleArray) {
        throw new UnsupportedOperationException("Only int data type is supported in fixedbit format");

    }

    @Override
    public void setStringArray(int row, String[] stringArray) {
        throw new UnsupportedOperationException("Only int data type is supported in fixedbit format");

    }

    @Override
    public void setBytesArray(int row, byte[][] bytesArray) {
        throw new UnsupportedOperationException("Only int data type is supported in fixedbit format");
    }

}