private static Class<?> box(Class<?> clazz) {
        if (clazz == int.class) {
            return Integer.class;
        } else
            if (clazz == float.class) {
                return Float.class;
            } else
                if (clazz == long.class) {
                    return Long.class;
                } else
                    if (clazz == double.class) {
                        return double.class;
                    } else
                        if (clazz == boolean.class) {
                            return Boolean.class;
                        } else
                            if (clazz == char.class) {
                                return Character.class;
                            } else
                                if (clazz == byte.class) {
                                    return Byte.class;
                                }
        return clazz;
    }
private static Class < ? > box ( Class < ? > clazz ) { if ( clazz == int . class ) { return Integer . class ; } else if ( clazz == float . class ) { return Float . class ; } else if ( clazz == long . class ) { return Long . class ; } else if ( clazz == double . class ) { return double . class ; } else if ( clazz == boolean . class ) { return Boolean . class ; } else if ( clazz == char . class ) { return Character . class ; } else if ( clazz == byte . class ) { return Byte . class ; } return clazz ; }
returns the boxed type of the primitive class or the
class itself if there is no wrapper for the given type.

@param clazz
@return