Large, locked islands precede 95% of the disruptions occurring in JET with an ITER-like wall . Electron cyclotron current drive can stabilize large islands and is planned for stabilization of tearing modes on ITER. The theory of current condensation  predicts a nonlinear amplification of power deposition due to the temperature sensitivity of ECCD, which improves stabilization efficiency by self-focusing power deposition at island O-points. Alternatively, premature nonlinear damping can occur at the island periphery, “shadowing” island center and reducing stabilization efficiency. The effect can be significant when large ECCD (~20MW for ITER) power is available. We present a numerical code OCCAMI (Of Current Condensation Amid Magnetic Islands)  and preliminary simulation results for possible experiments on ASDEX Upgrade (AUG) verifying the theory of current condensation.