(Review: ) IO streams are either character-oriented or byte-oriented.
Character-oriented IO has special features for handling character data.
Byte-oriented IO is for all types of data (including characters, if you want).
This chapter shows character-oriented output to a disk file
What class can used for writing characters to a file?
You know that the class will descend from
If you do not know what class you need, you could
in the Java documentation.
(Or you could search the Web.)
Does the class
FileWriter seem like a likely candidate?