com.streamsets.pipeline.lib.parser.delimited.DelimitedCharDataParser.java Source code

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Here is the source code for com.streamsets.pipeline.lib.parser.delimited.DelimitedCharDataParser.java

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/**
 * Copyright 2015 StreamSets Inc.
 *
 * Licensed under 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.streamsets.pipeline.lib.parser.delimited;

import com.streamsets.pipeline.api.Field;
import com.streamsets.pipeline.api.Record;
import com.streamsets.pipeline.api.Stage;
import com.streamsets.pipeline.api.impl.Utils;
import com.streamsets.pipeline.config.CsvHeader;
import com.streamsets.pipeline.config.CsvRecordType;
import com.streamsets.pipeline.lib.csv.OverrunCsvParser;
import com.streamsets.pipeline.lib.io.OverrunReader;
import com.streamsets.pipeline.lib.parser.AbstractDataParser;
import com.streamsets.pipeline.lib.parser.DataParserException;
import org.apache.commons.csv.CSVFormat;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

public class DelimitedCharDataParser extends AbstractDataParser {
    private final Stage.Context context;
    private final String readerId;
    private final OverrunCsvParser parser;
    private List<Field> headers;
    private boolean eof;
    private CsvRecordType recordType;

    public DelimitedCharDataParser(Stage.Context context, String readerId, OverrunReader reader, long readerOffset,
            int skipStartLines, CSVFormat format, CsvHeader header, int maxObjectLen, CsvRecordType recordType)
            throws IOException {
        this.context = context;
        this.readerId = readerId;
        this.recordType = recordType;
        switch (header) {
        case WITH_HEADER:
            format = format.withHeader((String[]) null).withSkipHeaderRecord(true);
            break;
        case IGNORE_HEADER:
            format = format.withHeader((String[]) null).withSkipHeaderRecord(true);
            break;
        case NO_HEADER:
            format = format.withHeader((String[]) null).withSkipHeaderRecord(false);
            break;
        default:
            throw new RuntimeException(Utils.format("Unknown header error: {}", header));
        }
        parser = new OverrunCsvParser(reader, format, readerOffset, skipStartLines, maxObjectLen);
        String[] hs = parser.getHeaders();
        if (header != CsvHeader.IGNORE_HEADER && hs != null) {
            headers = new ArrayList<>();
            for (String h : hs) {
                headers.add(Field.create(h));
            }
        }
    }

    @Override
    public Record parse() throws IOException, DataParserException {
        Record record = null;
        long offset = parser.getReaderPosition();
        String[] columns = parser.read();
        if (columns != null) {
            record = createRecord(offset, columns);
        } else {
            eof = true;
        }
        return record;
    }

    protected Record createRecord(long offset, String[] columns) throws DataParserException {
        Record record = context.createRecord(readerId + "::" + offset);

        if (recordType == CsvRecordType.LIST) {
            List<Field> row = new ArrayList<>();
            for (int i = 0; i < columns.length; i++) {
                Map<String, Field> cell = new HashMap<>();
                Field header = (headers != null) ? headers.get(i) : null;
                if (header != null) {
                    cell.put("header", header);
                }
                Field value = Field.create(columns[i]);
                cell.put("value", value);
                row.add(Field.create(cell));
            }
            record.set(Field.create(row));
        } else {
            LinkedHashMap<String, Field> listMap = new LinkedHashMap<>();
            for (int i = 0; i < columns.length; i++) {
                String key;
                Field header = (headers != null) ? headers.get(i) : null;
                if (header != null) {
                    key = header.getValueAsString();
                } else {
                    key = i + "";
                }
                listMap.put(key, Field.create(columns[i]));
            }
            record.set(Field.createListMap(listMap));
        }

        return record;
    }

    @Override
    public String getOffset() {
        return (eof) ? String.valueOf(-1) : String.valueOf(parser.getReaderPosition());
    }

    @Override
    public void close() throws IOException {
        parser.close();
    }

}