topic Java Enum while evaluating conditions in JUEL in Alfresco Archive

Java Enum while evaluating conditions in JUEL

mlisiewicz — Wed, 23 Mar 2011 12:01:21 GMT

Is it possible to use java enum while evaluating conditions in JUEL? e.g.I want to choose route from exclusive gateway based on state of process entity, where state is java enum. Comparison fails cause enum class is not visible in JUEL expression.${entity.getState() == JavaEnum.STATE1}I hope I made

Re: Java Enum while evaluating conditions in JUEL

jbarrez — Thu, 24 Mar 2011 06:40:45 GMT

what if you add the whole package of the enum? eg. org.activiti.enums.JavaEnum ?

Re: Java Enum while evaluating conditions in JUEL

mlisiewicz — Fri, 25 Mar 2011 16:20:30 GMT

This was obviously my second guess - unfortunately it doesn't work either.

Re: Java Enum while evaluating conditions in JUEL

frederikherema1 — Tue, 29 Mar 2011 06:36:29 GMT

This will work, although doesn't look as clean as it should :

${entity.getState().toString().equals("STATE")}

Re: Java Enum while evaluating conditions in JUEL

mlisiewicz — Fri, 01 Apr 2011 10:55:36 GMT

This will work, although doesn't look as clean as it should :

${entity.getState().toString().equals("STATE")}

Well,
in this case I read Your answer as: We just figured out that we do not support Java Enums
It's quite a drawback…

Re: Java Enum while evaluating conditions in JUEL

frederikherema1 — Fri, 01 Apr 2011 12:39:41 GMT

We just leverage UEL (JUEL), so it's actually not us not supporting Enums -> http://download.oracle.com/javaee/5/tutorial/doc/bnahq.html

When referencing an enum constant with an expression, you use a String literal. For example, consider this Enum class:

public enum Suit {hearts, spades, diamonds, clubs}
To refer to the Suit constant, Suit.hearts with an expression, you use the String literal, "hearts". Depending on the context, the String literal is converted to the enum constant automatically. For example, in the following expression in which mySuit is an instance of Suit, "hearts" is first converted to a Suit.hearts before it is compared to the instance.

${mySuit == "hearts"}

So the workaround is not a workaround, actually it's the way to do this… Don't really see what the drawback is. All there is to it, is their name, so typing in a literal string in an expression is exactly the same as using enum


${var == 'ORANGE'}
${var == MyEnum.ORANGE}

Re: Java Enum while evaluating conditions in JUEL

mlisiewicz — Fri, 01 Apr 2011 13:13:41 GMT

Actually You are right, it works like that :shock:
So the proper answer to my first post is:

${entity.getState() == "STATE1"}
or of course
${entity.getState().equals("STATE1")}

It does work in Activiti.