An inkjet printer for the labeling of goods has a housing having outlet openings for ink droplets on a front face, a printing mechanism, and two hydraulic couplings that are accessible on the outside of the housing. Each hydraulic coupling has a mechanical connection part and an automatically closing first valve. Each automatically closing first valve has a first valve body and a first pusher connected to the first valve body. A filter has a filter housing in which the filter medium is accommodated and on which two hydraulic mating couplings are disposed that are accessible from the outside of the filter housing. In a joined state of the two hydraulic couplings and the hydraulic mating couplings, the pushers are each in contact with each other and respectively keep the valve bodies connected to them in an opened state.