@Grapes(
    @Grab(group='com.opencsv', module='opencsv', version='4.1')
)
import com.opencsv.*
Writer writer = new StringWriter()
CSVWriter csvWriter = new CSVWriter(writer,
                    CSVWriter.DEFAULT_SEPARATOR, // tab일경우 (char) '\t'
                    CSVWriter.DEFAULT_QUOTE_CHARACTER,
                    CSVWriter.DEFAULT_ESCAPE_CHARACTER,
                    CSVWriter.DEFAULT_LINE_END)
csvWriter.writeNext(['Title1', 'Title2', 'Title3', 'Title4'] as String[])
csvWriter.writeNext(['value1', 'value2', 'value3', 'value4'] as Strign[])
...
csvWriter.close()
println writer.toString()