Hands-On Microservices with Kotlin

Understanding Spring Expression Language

We saw in our initial usage of the @Value annotation that we refer to it through an expression ${service.message.default} , this is a query in Spring Expression Language (SpEL).

But Spring provides a range of different kind of expressions that we can use:

• Arithmetic, +, -, *, /, %, ^, div, mod
• Relational, <, >, ==, !=, <=, >=, lt, gt, eq, ne, le, ge
• Logical,& and, or, not, ||, !
• Conditional, as Elvis operators
• Regular Expressions

//this should be 7@Value(value = "#{4+3}")private lateinit var result1 : Number//this should be one.value / another.value@Value(value = "#{ \${one.value} div \${another.value} }")private lateinit var result2 : Number//this should be one.value == another.value@Value(value ...