com.databasesandlife.util

Class CsvParser

java.lang.Object

com.databasesandlife.util.CsvParser

public class CsvParser
extends Object

Parses CSV files.

The CSV file is assumed to have a first line containing the column headings. Does not handle quotes in fields (e.g. as generated by Excel). Field names are case-sensitive. Files have a default character set (by default UTF-8) which can be changed by calling setDefaultCharset(java.nio.charset.Charset), however if the file has a Unicode BOM then this is accepted in preference to the default charset.

Usage

Create an object and set attributes such as the field-separator, list of acceptable columns, etc. Then either call parseAndCallHandler or parseToListOfMaps.

    CsvLineHandler myHandler = new CsvLineHandler() {
        void processCsvLine(Map<String,String> line) { .. }
    };
    CsvParser csvParser = new CsvParser();
    csvParser.setDesiredFields("abc","def"); // field set in file must be this set
    csvParser.setNonEmptyFields("abc");      // all of these fields must have non-empty values
    csvParser.parseAndCallHandler(myHandler, aFile);
    csvParser.parseAndCallHandler(myHandler, aReader);
    csvParser.parseAndCallHandler(myHandler, aClass);  // reads "aClass.csv" from classloader
    List<Map<String,String>> contents = csvParser.parseToListOfMaps(aFile);

Glossary

• Field - name of column
• Column index - e.g. 0 is the left-most column
• Line - a row of data or header

Author:

This source is copyright Adrian Smith and licensed under the LGPL 3.

See Also:

Project on GitHub

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	CsvParser.ArrayOfMapsLineHandler
static interface	CsvParser.CsvLineHandler
static class	CsvParser.MalformedCsvException

Field Summary

Fields

Modifier and Type	Field and Description
protected Charset	defaultCharset
protected Set<String>	desiredFields
protected Pattern	endOfDataRegex
protected String	fieldSeparator
protected Pattern	fieldSeparatorRegexp
protected boolean	ignoreNotDesiredColumns
protected Set<String>	nonEmptyFields
protected Pattern	skipLinePattern

Constructor Summary

Constructors

Constructor and Description
CsvParser()

Method Summary

Modifier and Type	Method and Description
protected String	getLineNumberText(int lineNumber)
void	parseAndCallHandler(CsvParser.CsvLineHandler lineHandler, BufferedReader r)
void	parseAndCallHandler(CsvParser.CsvLineHandler lineHandler, Class<?> cl)
void	parseAndCallHandler(CsvParser.CsvLineHandler lineHandler, File f)
List<Map<String,String>>	parseToListOfMaps(BufferedReader r)
List<Map<String,String>>	parseToListOfMaps(Class<?> cl)
List<Map<String,String>>	parseToListOfMaps(File f)
void	setDefaultCharset(Charset c)
void	setDesiredFields(String... f) Any fields found outside of this list cause an error
void	setEndOfDataRegex(Pattern p)
void	setFieldSeparator(String x)
void	setFieldSeparatorRegexp(Pattern p)
void	setIgnoreNotDesiredColumns(boolean b)
void	setNonEmptyFields(String... f) Any fields here must be present and have non-empty values
void	setSkipLinePattern(Pattern p)

Methods inherited from class java.lang.Object

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

Field Detail

defaultCharset

protected Charset defaultCharset

fieldSeparatorRegexp

protected Pattern fieldSeparatorRegexp

fieldSeparator

protected String fieldSeparator

desiredFields

protected Set<String> desiredFields

nonEmptyFields

protected Set<String> nonEmptyFields

endOfDataRegex

protected Pattern endOfDataRegex

ignoreNotDesiredColumns

protected boolean ignoreNotDesiredColumns

skipLinePattern

protected Pattern skipLinePattern

Constructor Detail

CsvParser

public CsvParser()

Method Detail

setEndOfDataRegex

public void setEndOfDataRegex(Pattern p)

setSkipLinePattern

public void setSkipLinePattern(Pattern p)

setDefaultCharset

public void setDefaultCharset(Charset c)

setFieldSeparatorRegexp

public void setFieldSeparatorRegexp(Pattern p)

setFieldSeparator

public void setFieldSeparator(String x)

setIgnoreNotDesiredColumns

public void setIgnoreNotDesiredColumns(boolean b)

setDesiredFields

public void setDesiredFields(String... f)

Any fields found outside of this list cause an error

setNonEmptyFields

public void setNonEmptyFields(String... f)

Any fields here must be present and have non-empty values

parseAndCallHandler

public void parseAndCallHandler(CsvParser.CsvLineHandler lineHandler,
                                BufferedReader r)
                         throws CsvParser.MalformedCsvException

Throws:

CsvParser.MalformedCsvException

parseAndCallHandler

public void parseAndCallHandler(CsvParser.CsvLineHandler lineHandler,
                                File f)
                         throws CsvParser.MalformedCsvException

Throws:

CsvParser.MalformedCsvException

parseAndCallHandler

public void parseAndCallHandler(CsvParser.CsvLineHandler lineHandler,
                                Class<?> cl)
                         throws CsvParser.MalformedCsvException

Throws:

CsvParser.MalformedCsvException

parseToListOfMaps

public List<Map<String,String>> parseToListOfMaps(BufferedReader r)
                                           throws CsvParser.MalformedCsvException

Throws:

CsvParser.MalformedCsvException

parseToListOfMaps

public List<Map<String,String>> parseToListOfMaps(File f)
                                           throws CsvParser.MalformedCsvException

Throws:

CsvParser.MalformedCsvException

parseToListOfMaps

public List<Map<String,String>> parseToListOfMaps(Class<?> cl)
                                           throws CsvParser.MalformedCsvException

Throws:

CsvParser.MalformedCsvException

getLineNumberText

protected String getLineNumberText(int lineNumber)