  Large-time asymptotic properties of solutions to a class of semilinear
stochastic wave equations with damping in a bounded domain are considered.
First an energy inequality and the exponential bound for a linear stochastic
equation are established. Under appropriate conditions, the existence theorem
for a unique global solution is given. Next the questions of bounded solutions
and the exponential stability of an equilibrium solution, in mean-square and
the almost sure sense, are studied. Then, under some sufficient conditions, the
existence of a unique invariant measure is proved. Two examples are presented
to illustrate some applications of the theorems.
