Casting numbers, dates, and booleans with Expression Language

Summary

Expression Language treats attributes as strings unless explicitly cast. Many failures happen because numeric or date comparisons require casting.

Symptom

• Numeric comparisons fail

• Date comparisons are incorrect

• Boolean logic always evaluates false

• Routing is inconsistent

Root Cause

• EL treats all attributes as strings by default

• “10” > “2” is true as a string but false as a number

• Dates must be parsed using EL functions

• Boolean attributes stored as strings require conversion

How to Fix It

Cast numbers

${field:toNumber()}

Cast booleans

${flag:toBoolean()}

Parse dates

${dateString:toDate():format('yyyy-MM-dd')}

Prevention

• Always cast before comparing

• Standardize date formats early

• Avoid storing numbers as mixed-format strings

Related Articles

• Expression Language reference

• Debugging routing logic

• Using toDate, toNumber, and toBoolean