![Getting Started with MEL
#[Payload]
#[Message.Payload]
#[Payload.inboundProperties.’http.status’]
#[Payload.outboundProperties.’http.queryParam’]](https://image.slidesharecdn.com/ashortintroductiononmuleexpressionlanguage-170220171327/85/A-short-introduction-on-mule-expression-language-5-320.jpg)
![Expressions in Mule
Mule Expression Language (MEL), which implements a single set of syntax rules that
no longer contains an evaluator. The evaluator, by default, is MEL itself, and it can
interpret expressions formerly associated with dozens of different evaluators. MEL
expressions are written according to the following format: #[expression]](https://image.slidesharecdn.com/ashortintroductiononmuleexpressionlanguage-170220171327/85/A-short-introduction-on-mule-expression-language-6-320.jpg)
A short introduction on mule expression language
- 1. A Short Introduction on Mule Expression Language By – Swapnil Sahu
- 2. What is Mule Expression Language? MEL is a lightweight, Mule-specific expression language that you can use to access and evaluate the data in the payload, properties and variables of a Mule message. Accessible and usable from within virtually every message processor in Mule, MEL enables you to quickly and elegantly filter, route, or otherwise act upon the different parts of the Mule message object.
- 3. Benefits of Using MEL • MEL is an expression language that provides a consistent, standardized way for developers to work with a Mule message’s payload, properties and variables. • MEL makes use of Mule-specific context objects, you can code it with the help of auto-complete • Great tool for evaluating expressions in your flows • Most importantly, MEL enforces consistency when accessing information in the Mule message: rather than using multiple expression evaluators, you can use MEL, the default expression evaluator, to consistently access and manipulate information. • MEL expressions work within message processors to modify the way the processors act upon the message such as routing or filtering.
- 4. Difference between MEL & scripting language An expression language, such as MEL, is similar, but not the same as, a scripting language: it allows you to write short scripts that resolve dynamically to get values, set values, or perform an operation on data. There is an overlap in functionality between an expression language and a scripting language, but scripting languages are generally more useful if you are writing something complex enough to require more than just a few lines of code, or if you need to include conditional logic. If, however, you need to get or set values, invoke methods, or perform functions, you can do so quickly and easily using an expression language.
- 5. Getting Started with MEL #[Payload] #[Message.Payload] #[Payload.inboundProperties.’http.status’] #[Payload.outboundProperties.’http.queryParam’]
- 6. Expressions in Mule Mule Expression Language (MEL), which implements a single set of syntax rules that no longer contains an evaluator. The evaluator, by default, is MEL itself, and it can interpret expressions formerly associated with dozens of different evaluators. MEL expressions are written according to the following format: #[expression]
- 7. Thank You