Question

I wrote a script parsing a .csv file in groovy using tokenize, which ended up not doing exactly what I needed, I am trying to use the openCSV library but I am unsure as to how I can parse out individual columns. here is my code so far:

List<String[]> rows = new CSVReader(
    new InputStreamReader(getClass().classLoader.getResourceAsStream(inputFileString)))
        .readAll()

        rows.each { row ->
            row.each { it ->
                println it
            }
        }

and here is my input data:

1,"unknown","positive","full message","I love it."

So what I am trying to figure out is how to print select columns in said row. Also thanks in advance, I am trying to get my head around groovy/java, I come from a Ruby background.

Answer 1

Not sure what you mean by ‘…how to print select columns in said row’

But this script (for example) prints the 4th column for each row:

@Grab( 'net.sf.opencsv:opencsv:2.3' )
import au.com.bytecode.opencsv.CSVReader

// This sets example to a 2 line string
// I'm using it instead of a file, as it makes
// an easier example to follow
def example = '''1,"unknown","positive","full message","I love it."
                |2,"tim","negative","whoop!","It's ok"'''.stripMargin()

List<String[]> rows = new CSVReader( new StringReader( example ) ).readAll()

rows.each {
  // print the 4th column
  println it[ 3 ]
}

That prints:

full message
whoop!