Groovy load .csv files

Question

How to read and import .csv file in groovy on grails. I have .csv file with data and
need to import in to db using user interface .

Answer 1

With Apache Commons-CSV

@Grab('org.apache.commons:commons-csv:1.2')
import org.apache.commons.csv.CSVParser
import static org.apache.commons.csv.CSVFormat.*

import java.nio.file.Paths

Paths.get('countryInfo.txt').withReader { reader ->
    CSVParser csv = new CSVParser(reader, DEFAULT.withHeader())

    for (record in csv.iterator()) {
        println record.dump()
    }
}

Commons-CSV has nice API and I recommend that.

---

With GroovyCSV:

@Grab('com.xlson.groovycsv:groovycsv:0.2')
import com.xlson.groovycsv.CsvParser

def csv = '''Name,Lastname
Mark,Andersson
Pete,Hansen'''

def data = new CsvParser().parse(csv)
for(line in data) {
    println "$line.Name $line.Lastname"
}

(Taken from it's samples)

---

Last resort: Regular expression.

Here's how I parsed a file that might contain a quoted escaped string in it's fourth column:

    File detailedStatsFile = new File("stats.csv");
    detailedStatsFile.eachLine { line, number ->
        // Number Of Executions, Total Milliseconds, Milliseconds per execution, "Type"
        def match = line =~ /([^,]*?),\s*([^,]*?),\s*([^,]*?),\s*(?:([^",]+)|(?:"((?:[^\\"]++(?:\\")?)++)"))$/; //"

        if (!match.matches())
            continue;

        def numberOfExecs = Integer.valueOf(match.group(1));
        def totalMillis = Integer.valueOf(match.group(2));
        def detailedStatName = match.group(4);
        if (detailedStatName == null)
            detailedStatName = match.group(5).replaceAll('\\"','"');