org.sfj

Class RFC4180CSVParser

java.lang.Object

org.sfj.RFC4180CSVParser

All Implemented Interfaces:

Closeable, AutoCloseable, Iterable<String[]>

public class RFC4180CSVParser
extends Object
implements Iterable<String[]>, Closeable

This attempts to implement a very tiny RFX4180 compliant CSV parser. It relies on BufferedReader's end of line handling, so it will swallow '\n', '\r' or '\r\n' line endings.

It attempts to implement the subset of RFV4180 called out on wikipedia:

• MS-DOS-style lines that end with (CR/LF) characters (optional for the last line).
• An optional header record (there is no sure way to detect whether it is present, so care is required when importing).
• Each record should contain the same number of comma-separated fields.
• Any field may be quoted (with double quotes).
• Fields containing a line-break, double-quote or commas should be quoted. (If they are not, the file will likely be impossible to process correctly.)
• If double-quotes are used to enclose fields, then a double-quote must be represented by two double-quote characters.

Additionally, it will ignore blank lines. The "header" line is not actually handled at all, you must handle it explicitly. It should handle quoted multi-line fields properly. You can, in the constructor, specify to parse a single header, which is then available via the getHeader() method.

Mainly, I implemented this simple subset because it is ... useful. If you need more than this, use a real library, like the excellent Apache one or OpenCSV, or, or, or.

Author:

cschanck

Constructor Summary

Constructors

Constructor and Description
RFC4180CSVParser(boolean hasHeader, Reader reader) Constructor, specifying if there is a header to read.
RFC4180CSVParser(char sep, boolean hasHeader, Reader reader) Constructor, specifying field separator, and if there is a header to read.
RFC4180CSVParser(Reader reader) Constructor, no header, comma seperator

Method Summary

Modifier and Type	Method and Description
void	close() Close this, close the reader.
String[]	getHeader() If reading a header was specified, then it can be retrieved via this method.
Iterator<String[]>	iterator()
String[]	record() Retrieve the next record in the CSV file.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

RFC4180CSVParser

public RFC4180CSVParser(Reader reader)
                 throws IOException

Constructor, no header, comma seperator

Parameters:

reader - reader to read.

Throws:

IOException - on IO exception

RFC4180CSVParser

public RFC4180CSVParser(boolean hasHeader,
                        Reader reader)
                 throws IOException

Constructor, specifying if there is a header to read.

Parameters:

hasHeader - true if there is a header to read

reader - reader

Throws:

IOException - on IO exception

RFC4180CSVParser

public RFC4180CSVParser(char sep,
                        boolean hasHeader,
                        Reader reader)
                 throws IOException

Constructor, specifying field separator, and if there is a header to read.

Parameters:

sep - character separator

hasHeader - true if there is a header to read

reader - reader

Throws:

IOException - on IO exception

Method Detail

getHeader

public String[] getHeader()

If reading a header was specified, then it can be retrieved via this method. If not specified, this will return null.

Returns:

header or null

close

public void close()

Close this, close the reader. Idempotent, swallows exceptions.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

iterator

public Iterator<String[]> iterator()

Specified by:

iterator in interface Iterable<String[]>

record

public String[] record()
                throws IOException

Retrieve the next record in the CSV file. Used as basis for iteration on this class, can be used directly if that is preferred.

Returns:

next record or null if at end of file.

Throws:

IOException - on exception