Expression Language Operators

Modified on Tue, Nov 28, 2023 at 9:13 AM

Click Here for a full list of expression functions

Expression Language is Very Flexible

The Expression Language itself is very powerful and flexible. “Expression Language” is what can occur between the “${“ open bracket and “}” close bracket. What can occur there includes the following:

- References to columns preceding the current Expression column in the list of columns:

Columns in the next row of output are referenced by saying ‘nextRow.column’. E.g. ${nextRow.studentName}, ${nextRow.gender}, ${nextRow.dateOfBirth}.
Columns in the previous row of the report are referenced by saying ‘prevRow.column’. E.g. ${prevRow.studentName}, ${prevRow.gender}, ${prevRow.dateOfBirth}.

- Parameters to the Report including both the built-in set of parameters and ‘user defined macros’ or parameters that you create on the Parameters tab of the Report. E.g. ${params.SchoolYear}.

- Literal strings. E.g. “Y”, “N”, “Daughter”, “Guardian 1”, etc.

- Literal numbers. Including:

Integers 17 922019
Decimal (floating point) numbers: 24.7 0.44
Exponential numbers: 1.2E4 (1.2 * 10**4 or 12000)

- Built-In Functions: A number of functions are provided by the ReportWriter Expression language. These can all appear in expressions. E.g. ${rw:toUpperCase(row.studentName)}

- Expression Language Operators: All of the ‘operators’ listed in the table below, including:

Conditional Expressions – “IF” statements that result in decisions being made within the column itself. See below the “Making Decisions in a Report” section.
Logical operators - which are always true or false
Relational operators - which are also always true or false
Arithmetic operations – which always result in numeric values.

- But NOT Dates: Dates cannot be input directly. E.g. 12/24/2011 becomes a STRING, not a DATE. Dates must be converted from Strings to an actual DATE via the ‘toDate’ Function. See below.

Operators

The full list of operators, values and functions that can appear in ‘expressions’ is below:

Expression Language Operators, Functions & Values	Examples
Arithmetic Operators
+	Add
-	Subtract
*	Multiply
/	Divide
%	Modulo (integer remainder) – Finds the remainder	10%4 = 2
Logical Operators
!	Not - unary ‘not’ operator. Reverses the truth of a test value.	!A or !empty
\|\|	Or - A \|\| B means ‘A or B’ – Either A or B must be *true*	A \|\| B
&&	And - A && B means ‘A and B’ must both be *true*	A && B
Relational Operators
==	Equal to	A == B or A eq B
!=	Not equal to	A != B or A ne B
<	Less than	A < B or A lt B
<=	Less than or equal to	A <= B or A le B
>	Greater than	A > B or A gt B
>=	Greater than or equal to	A >= B or A ge B
String compare functions
Contains	Test whether the column “contains” a certain String. Returns *true/false*.	rw:contains()
startsWith	Test whether the column “starts with” a certain String. Returns *true/false*.	rw:startsWith()
endsWith	Test whether the column “ends with” a certain String. Returns *true/false*.	rw:endsWith()
Date Compare
dateCompare(date1, date2)	Returns an integer value: 0 – same date (date1==date2) -1 – Date2 is earlier than Date 1 1 – Date 2 is later than Date 1	rw:dateCompare(today, params.startDate)
Programmatic
empty	Is the field empty?
!empty	Does the field have something in it? (is it not empty?)
Conditional Operator
?:	A? B : C – If A, then B else C
Special Values
true	Logical “true”. “Y” to the ReportWriter
false	Logical “false”. “N” to the ReportWriter
null	“Empty” – for testing fields
String Functions – These are provided to work with Strings
toUpperCase	Convert String to all upper case	rw:toUpperCase( params.SCHOOL_NAME)
toLowerCase	Convert String to all lower case	rw:toLowerCase(row.emailAddr)
initCaps	Convert String to all lower case then capitalize the first letter of each word	rw:initCaps(row.lastName)
Replace	Replace one piece of text with another	re.replace(row.lunch,”F”,”Free”)
Date Functions – These are provided to work with Dates
toDate	Convert a date String to an actual DATE.	rw:toDate(“07/24/2011”)
dateAddDays	Add X days to the startDate. X can be +-	rw:dateAddDays(row.aDate, -1) == yesterday
dateFindDayOfWeek	Find the “next X day” E.g. Find next Monday *plus X weeks*	rw:dateFindDay(today,”Mon”, 0) – Find next Monday
findCycleCode	Find the cycle of type *type* in which the *Date* falls,	rw:findCycleCode(today, params.SCHOOL_CODE, “Sports Season”)
getCycleStartDate	Find the first date in the *cycle*	rw:getCycleStartDate( params.SCHOOL_CODE, params.selectMP)
getCycleEndDate	Find the last date in the *cycle*	rw:getCycleEndDate( params.SCHOOL_CODE, params.selectMP)

getNumberOfDays	Get the number of days between two dates	rw:getNumberOfDays(fromDate,thruDate)
getDayOfYear	Get the numberical day of the year. E.g. Jan 24th is the 24th day of the year	rw:getDayOfYear(date)
Lookup Functions – Provided to lookup Descriptions for Generic Codes in Genesis
getCodeDescription	Lookup a Generic Code’s Description	rw:getCodeDescription('LANGUAGE_CODE', row.homeLanguageCode)