is it possible to import Java class to DMN in all the guides you have to make your own custom data object, but I have very complex class Application with more than 100 fields. Is there any way I can import this object to dmn for usage?
F.e. I have class Application and in dmn I want to change Application.user.data.value depending on Application.weather.hasSun condition?
The functionality of one-time import of Pojo as an automatic definition of ItemDefinition is only available in Business Central / Workbench.
You could use something like https://dmn-cli.com alternatively.
Finally, it's important to keep in mind that DMN is based on structural typing (and not nominal typing) so you don't need to define all "100 fields" in your DMN model ItemDefinition necessarily, but say you could only define the user and weather structure if those are only the fields in a ~JSON Schema that you make plan to use.