spring-tips / spel

Hi, Spring fans! In this installment we look at the Spring Expression Language

Spring Expression Language

History of Spring Expression Language

• JSP EL
• JSF EL
• JBoss EL
• OGNL
• Andy starts work on it. I'll never forget when he ripped out the Antlr code. Who does that?

A Tour of the Language

• LiteralExpressionsTest - literal expressions
• ArraysAndCollectionsTest - create literal arrays, collections, and maps
• MethodsTest - invoke custom methods
• OperatorsTest - can't ask questions if you can't compare things...
• TypesTest - work with the .class literal of a given type from SpEL
• VariablesTest - learn how to set and reference variables
• EvaluationContextsTest how to limit what may be evaluated in production
• RootObjectsTest - learn how to control the root object on which property accesses dereference
• SelectionsTest - learn how to filter collections or maps with selections
• NavigationsTest - the language makes it easy and safe to navigate property stacks
• SpringTest - see how the SpEL works with and within a Spring application.
• CompilationTest - did you know you can compile the Spring Expression Language statement?? Spring Integration knows this. And they use it well.
• SpelApplication - this example was inspired by this amazing commit from Marcus da Coregio who shows how to, given a SpEL expression - in this case extracted from annotations that Spring cares about - register the corresponding bean for reflection using the Spring AOT component model.