org.apache.tajo.plan.function.stream.CSVLineDeserializer.java Source code

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Here is the source code for org.apache.tajo.plan.function.stream.CSVLineDeserializer.java

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/**
 * 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.tajo.plan.function.stream;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufProcessor;
import org.apache.tajo.catalog.Schema;
import org.apache.tajo.catalog.TableMeta;
import org.apache.tajo.datum.Datum;
import org.apache.tajo.storage.Tuple;

import java.io.IOException;

public class CSVLineDeserializer extends TextLineDeserializer {
    private ByteBufProcessor processor;
    private FieldSerializerDeserializer fieldSerDer;
    private ByteBuf nullChars;
    private int delimiterCompensation;

    public CSVLineDeserializer(Schema schema, TableMeta meta, int[] targetColumnIndexes) {
        super(schema, meta, targetColumnIndexes);
    }

    @Override
    public void init() {
        byte[] delimiter = CSVLineSerDe.getFieldDelimiter(meta);
        this.processor = new FieldSplitProcessor(delimiter[0]);
        this.delimiterCompensation = delimiter.length - 1;

        if (nullChars != null) {
            nullChars.release();
        }
        nullChars = TextLineSerDe.getNullChars(meta);

        fieldSerDer = new TextFieldSerializerDeserializer(meta);
    }

    public void deserialize(final ByteBuf lineBuf, Tuple output) throws IOException, TextLineParsingError {
        int[] projection = targetColumnIndexes;
        if (lineBuf == null || targetColumnIndexes == null || targetColumnIndexes.length == 0) {
            return;
        }

        final int rowLength = lineBuf.readableBytes();
        int start = 0, fieldLength = 0, end = 0;

        //Projection
        int currentTarget = 0;
        int currentIndex = 0;

        while (end != -1) {
            end = lineBuf.forEachByte(start, rowLength - start, processor);

            if (end < 0) {
                fieldLength = rowLength - start;
            } else {
                fieldLength = end - start - delimiterCompensation;
            }

            if (projection.length > currentTarget && currentIndex == projection[currentTarget]) {
                lineBuf.setIndex(start, start + fieldLength);
                Datum datum = fieldSerDer.deserialize(lineBuf, schema.getColumn(currentIndex), currentIndex,
                        nullChars);
                output.put(currentIndex, datum);
                currentTarget++;
            }

            if (projection.length == currentTarget) {
                break;
            }

            start = end + 1;
            currentIndex++;
        }
    }

    @Override
    public void release() {
        if (nullChars != null) {
            nullChars.release();
            nullChars = null;
        }
    }
}