org.apache.hive.beeline.SeparatedValuesOutputFormat.java Source code

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Here is the source code for org.apache.hive.beeline.SeparatedValuesOutputFormat.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.
 */

/*
 * This source file is based on code taken from SQLLine 1.0.2
 * See SQLLine notice in LICENSE
 */
package org.apache.hive.beeline;

import org.apache.commons.io.output.StringBuilderWriter;
import org.apache.commons.lang.BooleanUtils;
import org.apache.commons.lang.StringUtils;
import org.supercsv.encoder.CsvEncoder;
import org.supercsv.encoder.DefaultCsvEncoder;
import org.supercsv.encoder.SelectiveCsvEncoder;
import org.supercsv.io.CsvListWriter;
import org.supercsv.prefs.CsvPreference;

/**
 * OutputFormat for values separated by a configurable delimiter
 */
class SeparatedValuesOutputFormat implements OutputFormat {

    public final static String DSV_OPT_OUTPUT_FORMAT = "dsv";
    public final static String DISABLE_QUOTING_FOR_SV = "disable.quoting.for.sv";
    private final static char DEFAULT_QUOTE_CHAR = '"';
    private final BeeLine beeLine;
    private final StringBuilderWriter buffer;
    private final char defaultSeparator;

    SeparatedValuesOutputFormat(BeeLine beeLine, char separator) {
        this.beeLine = beeLine;
        this.defaultSeparator = separator;
        this.buffer = new StringBuilderWriter();
    }

    private CsvPreference getCsvPreference() {
        char separator = this.defaultSeparator;
        char quoteChar = DEFAULT_QUOTE_CHAR;
        CsvEncoder encoder;

        if (DSV_OPT_OUTPUT_FORMAT.equals(beeLine.getOpts().getOutputFormat())) {
            separator = beeLine.getOpts().getDelimiterForDSV();
        }

        if (isQuotingDisabled()) {
            quoteChar = '\0';
            encoder = new SelectiveCsvEncoder();
        } else {
            encoder = new DefaultCsvEncoder();
        }

        return new CsvPreference.Builder(quoteChar, separator, StringUtils.EMPTY).useEncoder(encoder).build();
    }

    @Override
    public int print(Rows rows) {
        CsvPreference csvPreference = getCsvPreference();
        CsvListWriter writer = new CsvListWriter(this.buffer, csvPreference);
        int count = 0;

        Rows.Row labels = (Rows.Row) rows.next();
        if (beeLine.getOpts().getShowHeader()) {
            fillBuffer(writer, labels);
            String line = getLine(this.buffer);
            beeLine.output(line);
        }

        while (rows.hasNext()) {
            fillBuffer(writer, (Rows.Row) rows.next());
            String line = getLine(this.buffer);
            beeLine.output(line);
            count++;
        }

        return count;
    }

    /**
     * Fills the class's internal buffer with a DSV line
     */
    private void fillBuffer(CsvListWriter writer, Rows.Row row) {
        String[] vals = row.values;

        try {
            writer.write(vals);
            writer.flush();
        } catch (Exception e) {
            beeLine.error(e);
        }
    }

    private String getLine(StringBuilderWriter buf) {
        String line = buf.toString();
        buf.getBuilder().setLength(0);
        return line;
    }

    /**
     * Default is disabling the double quoting for separated value
     */
    private boolean isQuotingDisabled() {
        Boolean quotingDisabled = Boolean.TRUE;
        String quotingDisabledStr = System.getProperty(SeparatedValuesOutputFormat.DISABLE_QUOTING_FOR_SV);

        if (StringUtils.isNotBlank(quotingDisabledStr)) {
            quotingDisabled = BooleanUtils.toBooleanObject(quotingDisabledStr);

            if (quotingDisabled == null) {
                beeLine.error("System Property " + SeparatedValuesOutputFormat.DISABLE_QUOTING_FOR_SV + " is now "
                        + quotingDisabledStr + " which only accepts boolean values");
                quotingDisabled = Boolean.TRUE;
            }
        }
        return quotingDisabled;
    }
}