java-mcsv - A MetaCSV library for Java

Copyright (C) 2020 J. Férard https://github.com/jferard

License: GPLv3

Overview

py-mcsv is a MetaCSV library for Java. I quote the README:

MetaCSV is an open specification for a CSV file description. This description is written in a small auxiliary CSV file that may be stored along wih the CSV file itself. This auxiliary file should provide the information necessary to read and type the content of the CSV file. The standard extension is ".mcsv".

Java-mcsv is able to read and type the rows of a CSV file, provided that you have an appropriate MetaCSV file.

(The ColumnDet package is able to generate automatically a sensible MetaCSV file for a given CSV file.)

Example

Here's a basic example. The example.csv file reads (encoding: utf-8, newline: CRLF):

name,date,count
foo,2020-11-21,15
foo,2020-11-22,-8

The example.mcsv file reads (encoding: utf-8, newline: CRLF, see the MetaCSV format specification):

domain,key,value
data,col/1/type,date/YYYY-MM-dd
data,col/2/type,integer

The code is:

File f = getResourceAsFile("example.csv");
com.github.jferard.javamcsv.MetaCSVReader reader = com.github.jferard.javamcsv.MetaCSVReader.create(f);
System.out.println(reader.getDescriptions());
for (com.github.jferard.javamcsv.MetaCSVRecord record : reader) {
    System.out.println(record);
}

Output:

{1=date/YYYY-MM-dd, 2=integer}
com.github.jferard.javamcsv.MetaCSVRecord(CSVRecord [comment=null, mapping=null, recordNumber=1, values=[name, date, count]] ,[name, date, count])
com.github.jferard.javamcsv.MetaCSVRecord(CSVRecord [comment=null, mapping=null, recordNumber=2, values=[foo, 2020-11-21, 15]] ,[foo, Mon Dec 30 00:00:00 CET 2019, 15])
com.github.jferard.javamcsv.MetaCSVRecord(CSVRecord [comment=null, mapping=null, recordNumber=3, values=[foo, 2020-11-22, -8]] ,[foo, Mon Dec 30 00:00:00 CET 2019, -8])