The holes move in the direction of applied electric field and the current density due to them is given as μhnieE.
The electrons move in the direction opposite to that of the electric field, and current due to that is in the direction opposite to that of the movement of electrons, that is, in the direction of the electric field.
Current density due to movement of electrons is μ2n1eE.
Hence total current density =Jh+Je=nie(μe+μh)E