org.apache.poi.ss.formula.eval

Class RelationalOperationEval

java.lang.Object

org.apache.poi.ss.formula.functions.Fixed2ArgFunction

org.apache.poi.ss.formula.eval.RelationalOperationEval

All Implemented Interfaces:

ArrayFunction, Function, Function2Arg

public abstract class RelationalOperationEval
extends Fixed2ArgFunction
implements ArrayFunction

Base class for all comparison operator evaluators

Author:

Amol S. Deshmukh < amolweb at ya hoo dot com >

Field Summary

Fields

Modifier and Type	Field and Description
static Function	EqualEval
static Function	GreaterEqualEval
static Function	GreaterThanEval
static Function	LessEqualEval
static Function	LessThanEval
static Function	NotEqualEval

Constructor Summary

Constructors

Constructor and Description
RelationalOperationEval()

Method Summary

Modifier and Type	Method and Description
protected abstract boolean	convertComparisonResult(int cmpResult) Converts a standard compare result (-1, 0, 1) to true or false according to subclass' comparison type.
ValueEval	evaluate(int srcRowIndex, int srcColumnIndex, ValueEval arg0, ValueEval arg1) This is a description of how the relational operators apply in MS Excel.
ValueEval	evaluateArray(ValueEval[] args, int srcRowIndex, int srcColumnIndex)

Methods inherited from class org.apache.poi.ss.formula.functions.Fixed2ArgFunction

evaluate

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.poi.ss.formula.functions.ArrayFunction

evaluateOneArrayArg, evaluateTwoArrayArgs

Field Detail

EqualEval

public static final Function EqualEval

GreaterEqualEval

public static final Function GreaterEqualEval

GreaterThanEval

public static final Function GreaterThanEval

LessEqualEval

public static final Function LessEqualEval

LessThanEval

public static final Function LessThanEval

NotEqualEval

public static final Function NotEqualEval

Constructor Detail

RelationalOperationEval

public RelationalOperationEval()

Method Detail

convertComparisonResult

protected abstract boolean convertComparisonResult(int cmpResult)

Converts a standard compare result (-1, 0, 1) to true or false according to subclass' comparison type.

evaluate

public ValueEval evaluate(int srcRowIndex,
                          int srcColumnIndex,
                          ValueEval arg0,
                          ValueEval arg1)

This is a description of how the relational operators apply in MS Excel. Use this as a guideline when testing/implementing the evaluate methods for the relational operators Evals.

 Bool.TRUE > any number.
 Bool > any string. ALWAYS
 Bool.TRUE > Bool.FALSE
 Bool.FALSE == Blank

 Strings are never converted to numbers or booleans
 String > any number. ALWAYS
 Non-empty String > Blank
 Empty String == Blank
 String are sorted dictionary wise

 Blank > Negative numbers
 Blank == 0
 Blank < Positive numbers
 

Specified by:

evaluate in interface Function2Arg

evaluateArray

public ValueEval evaluateArray(ValueEval[] args,
                               int srcRowIndex,
                               int srcColumnIndex)

Specified by:

evaluateArray in interface ArrayFunction

Parameters:

args - the evaluated function arguments. Empty values are represented with BlankEval or MissingArgEval, never null.

srcRowIndex - row index of the cell containing the formula under evaluation

srcColumnIndex - column index of the cell containing the formula under evaluation

Returns:

The evaluated result, possibly an ErrorEval, never null. Note - Excel uses the error code #NUM! instead of IEEE NaN, so when numeric functions evaluate to Double.NaN be sure to translate the result to ErrorEval.NUM_ERROR.