Package net.sf.basedb.util.parser

Class ColFunction

java.lang.Object

net.sf.basedb.util.parser.ColFunction

All Implemented Interfaces:

JepFunction, org.nfunk.jep.function.PostfixMathCommandI

public class ColFunction
extends Object
implements JepFunction

Adds a col() function to Jep. The col function is used with the FlatFileParser to get the value of a data column. The argument to the col function is either the column name or index (0-based). Use the FlatFileParser.getMapper(String) with an argument starting with an equal sign to create a mapper that uses Jep.

FlatFileParser ffp = ...
Mapper diameterMapper = ffp.getMapper("=col('Radius') * 2");
while (ffp.hasMoreData())
{
        Data data = ffp.nextData();
        float diameter = diameterMapper.getFloat(data);
}

Version:

2.0

Author:

nicklas

Last modified

$Date: 2019-03-21 13:37:48 +0100 (tors, 21 mars 2019) $

Field Summary

Fields

Modifier and Type	Field	Description
private final Map<String,Integer>	columnHeaders
private FlatFileParser.Data	data
private final Formatter<Date>	dateFormat
private boolean	ignoreNonExistingColumns
private Type	nextValueType
private final NumberFormat	numberFormat
private final ParsePosition	pos

Constructor Summary

Constructors

Constructor	Description
ColFunction(List<String> columnHeaders, NumberFormat numberFormat)
ColFunction(List<String> columnHeaders, NumberFormat numberFormat, Formatter<Date> dateFormat)
ColFunction(Map<String,Integer> columnHeaders, NumberFormat numberFormat)
ColFunction(Map<String,Integer> columnHeaders, NumberFormat numberFormat, Formatter<Date> dateFormat)

Method Summary

Modifier and Type	Method	Description
boolean	checkNumberOfParameters(int n)
private Integer	findColumn(String regex)	Find column index by checking each column header against a regular expression.
String	getFunctionName()	Get the name of this function.
int	getNumberOfParameters()
void	run(Stack stack)
void	setCurNumberOfParameters(int n)
void	setData(FlatFileParser.Data data, Type valueType)
void	setIgnoreNonExistingColumns(boolean ignoreNonExistingColumns)	Set to TRUE to ignore non-existing columns.

Methods inherited from class java.lang.Object

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

Field Details

columnHeaders

private final Map<String,Integer> columnHeaders

numberFormat

private final NumberFormat numberFormat

dateFormat

private final Formatter<Date> dateFormat

pos

private final ParsePosition pos

data

private FlatFileParser.Data data

nextValueType

private Type nextValueType

ignoreNonExistingColumns

private boolean ignoreNonExistingColumns

Constructor Details

ColFunction

public ColFunction(Map<String,Integer> columnHeaders,
 NumberFormat numberFormat)

ColFunction

public ColFunction(Map<String,Integer> columnHeaders,
 NumberFormat numberFormat,
 Formatter<Date> dateFormat)

Since:

3.15

ColFunction

public ColFunction(List<String> columnHeaders,
 NumberFormat numberFormat)

ColFunction

public ColFunction(List<String> columnHeaders,
 NumberFormat numberFormat,
 Formatter<Date> dateFormat)

Since:

3.15

Method Details

getFunctionName

public String getFunctionName()

Description copied from interface: JepFunction

Get the name of this function. It is used when registering the function with a JEP parser.

Specified by:

getFunctionName in interface JepFunction

Returns:

The string "col"

See Also:

• JEP.addFunction(String, PostfixMathCommandI)

getNumberOfParameters

public int getNumberOfParameters()

Specified by:

getNumberOfParameters in interface org.nfunk.jep.function.PostfixMathCommandI

Returns:

Always 1

setCurNumberOfParameters

public void setCurNumberOfParameters(int n)

Specified by:

setCurNumberOfParameters in interface org.nfunk.jep.function.PostfixMathCommandI

checkNumberOfParameters

public boolean checkNumberOfParameters(int n)

Specified by:

checkNumberOfParameters in interface org.nfunk.jep.function.PostfixMathCommandI

run

public void run(Stack stack)
         throws ParseException

Specified by:

run in interface org.nfunk.jep.function.PostfixMathCommandI

Throws:

ParseException

setIgnoreNonExistingColumns

public void setIgnoreNonExistingColumns(boolean ignoreNonExistingColumns)

Set to TRUE to ignore non-existing columns. Set to FALSE to throw an exception (default).

Since:

2.6

setData

public void setData(FlatFileParser.Data data,
 Type valueType)

findColumn

private Integer findColumn(String regex)

Find column index by checking each column header against a regular expression. The first match found is returned. The map is updated with a new regex -> index entry.

Returns:

The column index or null if no column is found or if the string is not a valid regular expression