  Global structure of the (anti-)de~Sitter ((A)dS) generalization of the
Roberts solution in general relativity with a massless scalar field and its
topological generalization is clarified. In the case with a negative
cosmological constant, the spacetime is asymptotically locally AdS and it
contains a black-hole event horizon depending on the parameters. The spacetime
may be attached to the exact AdS spacetime in a regular manner on a null
hypersurface and the resulting spacetime represents gravitational collapse from
a regular initial datum. The higher-dimensional counterpart of this
Roberts-(A)dS solution with flat base manifold is also given.
