  The information-spectrum analysis made by Han for classical hypothesis
testing for simple hypotheses is extended to a unifying framework including
both classical and quantum hypothesis testing as well as fixed-length source
coding, whereby general formulas for several quantities concerning the
asymptotic optimality of tests/codes are established in terms of classical and
quantum information spectrum. Generality of theorems and simplicity of proofs
are fully pursued, and as byproducts some improvements on the original
classical results are also obtained.
