doubt about contourn of residue theorem

Question

How can I calculate the value of these integrals

$\int_{0}^{\infty} \dfrac{we^{it(w+w_b)}}{w-w_a}dw\\$

$\int_{0}^{\infty} \dfrac{we^{it(w+w_b)}}{w+w_a}dw$

where $w_a>0$ and $w_b>0.$

I would like to use the residue theorem, but I do not understand how to close the contours, could someone explain to me?

thanks