  Using the tools of the J-matrix method, we absorb the 1/r singularity of the
Yukawa potential in the reference Hamiltonian, which is handled analytically.
The remaining part, which is bound and regular everywhere, is treated by an
efficient numerical scheme in a suitable basis using Gauss quadrature
approximation. Analysis of resonance energies and bound states spectrum is
performed using the complex scaling method, where we show their trajectories in
the complex energy plane and demonstrate the remarkable fact that bound states
cross over into resonance states by varying the potential parameters.
