Originally posted by: TobiasUni-Hohenheim

Hi,

in the console we can use

CPLEX> change problem type

to change the problem type. How can we achieve this via the Java API?

Thanks.
#CPLEXOptimizers
#DecisionOptimization

Originally posted by: SystemAdmin

From the reference documentation of class ilog.cplex.IloCplex:

IloCplex effectively treats all models as MIQCP models. That is, it allows the most general case, although the solution algorithms make efficient use of special cases, such as the absence of quadratic terms in the formulation.

If you read on in the reference documentation of the class you will find that IloCplex.solve() automatically determines the type of the problem based on what kind of constraints/variables it finds in the model. If you want to do temporary changes to your model (like changing a variable type) then ilog.concert.IloConversion may be helpful.
#CPLEXOptimizers
#DecisionOptimization