If both methods have same parameter types, but different return type than it is not possible. From Java Language Specification, Java SE 8 Edition, §8.4.2. Method Signature:
Two methods or constructors, M and N, have the same signature if they have the same name, the same type parameters (if any) (§8.4.4), and, after adapting the formal parameter types of N to the the type parameters of M, the same formal parameter types.
If both methods has different parameter types (so, they have different signature), then it is possible. It is called overloading.