Integer i = Integer.valueOf(0);
Character.valueOf(i); // requires a char in argument
You can try Character#toChars(int) and discard the superfluous character, if there is one generated (see the documentation for more infos on behavior of the method).
//just a stub to show how the code works. Might not work in all cases!!! Integer i = ...; Character c = Character.toChars(i);
Note though that this is only a cosmetic action involving quite a load of autoboxing. The JavaAPI is built around the primitives and
Character and other wrapper-classes are merely more than a mixture of utility-classes and (as the name suggests) wrappers for primitives.
In general java is based on the primitive-types, so avoiding them would be a workaround for the way the language is designed. Rather unnatural IMO.