This version is still in development and is not considered stable yet. For the latest stable version, please use Spring Framework 6.2.1!

Inline Lists

You can directly express lists in an expression by using {} notation.

  • Java

  • Kotlin

// evaluates to a Java list containing the four numbers
List numbers = (List) parser.parseExpression("{1,2,3,4}").getValue(context);

List listOfLists = (List) parser.parseExpression("{{'a','b'},{'x','y'}}").getValue(context);
// evaluates to a Java list containing the four numbers
val numbers = parser.parseExpression("{1,2,3,4}").getValue(context) as List<*>

val listOfLists = parser.parseExpression("{{'a','b'},{'x','y'}}").getValue(context) as List<*>

{} by itself means an empty list. For performance reasons, if the list is itself entirely composed of fixed literals, a constant list is created to represent the expression (rather than building a new list on each evaluation).