We discuss hadron-tomography studies for the nucleon and exotic hadrons by high-energy hadron reactions. First, the constituent-counting rule is explained for determining internal quark configurations of exotic-hadron candidates by scaling properties of high-energy exclusive cross sections. Next, possibilities are discussed for investigating the generalized parton distributions (GPDs) of the nucleon and exotic hadrons at J-PARC. In particular, we study hadronic $2 \to 3$ process $p+p \to N+\pi+B$, exclusive Drell-Yan process, and exotic-hadron GPDs. For determining three-dimensional structure of unstable exotic hadrons, we consider $s$-$t$ crossed quantities of the GPDs called generalized distribution amplitudes (GDAs), which can be investigated at KEKB. We explain possible studies of the GDAs by two-photon processes.