com.ibm.bi.dml.runtime.transform.DistinctValue.java Source code

Introduction

Here is the source code for com.ibm.bi.dml.runtime.transform.DistinctValue.java

Source

/**
 * (C) Copyright IBM Corp. 2010, 2015
 *
 * 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.ibm.bi.dml.runtime.transform;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.io.Serializable;
import java.nio.ByteBuffer;
import java.nio.charset.CharacterCodingException;
import java.nio.charset.Charset;

import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableUtils;

import com.ibm.bi.dml.runtime.matrix.CSVReblockMR.OffsetCount;
import com.ibm.bi.dml.runtime.util.UtilFunctions;

public class DistinctValue implements Writable, Serializable {

    private static final long serialVersionUID = -8236705946336974836L;

    private static final byte[] EMPTY_BYTES = new byte[0];

    // word (distinct value)
    private byte[] _bytes;
    private int _length;
    // count
    private long _count;

    public DistinctValue() {
        _bytes = EMPTY_BYTES;
        _length = 0;
        _count = -1;
    }

    public DistinctValue(String w, long count) throws CharacterCodingException {
        ByteBuffer bb = Text.encode(w, true);
        _bytes = bb.array();
        _length = bb.limit();
        _count = count;
    }

    public DistinctValue(OffsetCount oc) throws CharacterCodingException {
        this(oc.filename + "," + oc.fileOffset, oc.count);
    }

    public void reset() {
        _bytes = EMPTY_BYTES;
        _length = 0;
        _count = -1;
    }

    public String getWord() {
        return new String(_bytes, 0, _length, Charset.forName("UTF-8"));
    }

    public long getCount() {
        return _count;
    }

    @Override
    public void write(DataOutput out) throws IOException {
        // write word
        WritableUtils.writeVInt(out, _length);
        out.write(_bytes, 0, _length);
        // write count
        out.writeLong(_count);
    }

    @Override
    public void readFields(DataInput in) throws IOException {
        // read word 
        int newLength = WritableUtils.readVInt(in);
        _bytes = new byte[newLength];
        in.readFully(_bytes, 0, newLength);
        _length = newLength;
        if (_length != _bytes.length)
            System.out.println("ERROR in DistinctValue.readFields()");
        // read count
        _count = in.readLong();
    }

    public OffsetCount getOffsetCount() {
        OffsetCount oc = new OffsetCount();
        String[] parts = getWord().split(",");
        oc.filename = parts[0];
        oc.fileOffset = UtilFunctions.parseToLong(parts[1]);
        oc.count = getCount();

        return oc;
    }

}