  Reaction theory is an essential ingredient when performing studies of nuclei
far from stability. One approach for the calculation of breakup reactions of
exotic nuclei into two fragments is to consider inelastic excitations into the
single particle continuum of the projectile. Alternatively one can also
consider the transfer to the continuum of a system composed of the light
fragment and the target. In this work we make a comparative study of the two
approaches, underline the different inputs, and identify the advantages and
disadvantages of each approach. Our test cases consist of the breakup of
$^{11}$Be on a proton target at intermediate energies, and the breakup of $^8$B
on $^{58}$Ni at energies around the Coulomb barrier. We find that, in practice
the results obtained in both schemes are in semiquantitative agreement. We
suggest a simple condition that can select between the two approaches.
