HSQLDB example source code file (CSVWriter.java)

This example HSQLDB source code file (CSVWriter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - HSQLDB tags/keywords

csvwriter, fileoutputstream, io, ioexception, ioexception, outputstreamwriter, outputstreamwriter, string, string, stringbuffer, stringbuffer

The HSQLDB CSVWriter.java source code

/* Copyright (c) 2001-2008, The HSQL Development Group
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the HSQL Development Group nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL HSQL DEVELOPMENT GROUP, HSQLDB.ORG,
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


package org.hsqldb.util;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;

/**
 * helper class to write table data to a csv-file (comma separated values).
 * the first line in file is a list of fieldnames, all following lines
 * are data lines.
 * a descptiontion of file format can be found on: http://www.wotsit.org/
 * usage: create a object using the constructor. call writeHeader
 * for writing the filename header then add data with writeData.
 * at the end close() closes the file.
 *
 *@author jeberle@users
 */
public class CSVWriter {

    private String             newline = System.getProperty("line.separator");
    private OutputStreamWriter writer  = null;
    private int                nbrCols = 0;
    private int                nbrRows = 0;

    /**
     * constructor.
     * creates a csv file for writing data to it
     * @param file the file to write data to
     * @param encoding encoding to use or null (=defualt)
     */
    public CSVWriter(File file, String encoding) throws IOException {

        if (encoding == null) {
            encoding = System.getProperty("file.encoding");
        }

        FileOutputStream fout = new FileOutputStream(file);

        writer = new OutputStreamWriter(fout, encoding);
    }

    /**
     * writes the csv header (fieldnames). should be called after
     * construction one time.
     * @param header String[] with fieldnames
     */
    public void writeHeader(String[] header) throws IOException {

        this.nbrCols = header.length;

        doWriteData(header);
    }

    /**
     * writes a data-record to the file. note that data[] must have
     * same number of elements as the header had.
     *
     * @param data data to write to csv-file
     */
    public void writeData(String[] data) throws IOException {
        doWriteData(data);
    }

    /**
     * closes the csv file.
     */
    public void close() throws IOException {
        this.writer.close();
    }

    private void doWriteData(String[] values) throws IOException {

        for (int i = 0; i < values.length; i++) {
            if (i > 0) {
                this.writer.write(";");
            }

            if (values[i] != null) {
                this.writer.write("\"");
                this.writer.write(this.toCsvValue(values[i]));
                this.writer.write("\"");
            }
        }

        this.writer.write(newline);

        this.nbrRows++;
    }

    private String toCsvValue(String str) {

        StringBuffer sb = new StringBuffer();

        for (int i = 0; i < str.length(); i++) {
            char c = str.charAt(i);

            sb.append(c);

            switch (c) {

                case '"' :
                    sb.append('"');
                    break;
            }
        }

        return sb.toString();
    }
}