CODEWITHSUNDEEP
freemarker
nealons
nealons

Reputation: 25

Get Class of Map in FreeMarker

I want to get a variable's class type in freemarker, used var.class.simpleName; but if var is a Map, freemarker will process class as a key to find value in var. it throw exception. how can I do this ? thanks for any suggestion.

Upvotes: 0

Views: 383

Answers (1)

ddekany
ddekany

Reputation: 31112

First I have to ask why do you need that, because FreeMarker templates aren't supposed to know even if var is Map at all. Maybe your data-model is not what the template needs.

Anyway, for now, I would write a custom TemplateMethodModelEx for this purpose, something that you can use like ${classOf(var)}. Inside the TemplateMethodModelEx implementation you will receive a TemplateModel as the argument value, and then you can check if it's an AdapterTemplateModel, and if so you can get back the original object and get its class. (If it's not a AdapterTemplateModel, then it perhaps isn't even a wrapped Java object, so it doesn't make sense to ask what the class of the original object is.) However, the DefaultObjectWrapper with incompatibleImprovements set to less than 2.3.22 doesn't give AdapterTemplateModel to wrapped Map-s... so in 2.3.21 you will still have to use BeansWrapper, but you can at least set simpleMapWrapper to true.

In 2.3.22 it will be actually possible to write ${var?api.class}... you might use the nightly build. Though it only supposed to solve the problem where you can't access business methods because the primary type of the business class is Map.

Upvotes: 1

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