fi = open("myfile.txt", "r", encoding="windows-1252");
fo = open("output.txt", "w", "utf-8");
fo.write(fi.read());

=>

Reader fi = new InputStreamReader(new FileInputStream("myfile.txt"), "windows-1252"));
Writer fo = new OutputStreamWriter(new FileOutputStram("output.txt"), "utf-8"));
fo.write(fi.read()); // well, not exactly this syntax, but...