Rapist violate another human, and this kind of crime should be punishable by torture until the rapist just wishes he would die.
This crime is very in humane and I think they deserve to punish first.
Sexual Violators, Cat callers should be punished too.
In most of the third world nations, rape is even worse than murder. Because the victim's life is destroyed for ever. The level of social stigma and harassment she will face for the rest of her life is unimaginable. Therefore, the rapist also must be given very tough punishments. As a first step, he should be raped with a foreign object. After that, he should be sent to a penal colony, where he should spend the rest of his life.
I don't see a problem with Cat Callers but rapists should definitely be harshly punished. For humane reasons, even for rapists, I would however suggest not a foreign object to rape him with, but familiar ones, the types penal colonies are full of, provided this penal place is gender specific of course.