Follow-up to 0a6a85e

See investigation in b/269345183

PiperOrigin-RevId: 509647966

Author: cushon

core/src/main/java/com/google/googlejavaformat/java/Main.java

@@ -137,7 +137,8 @@ private int formatFiles(CommandLineOptions parameters, JavaFormatterOptions opti
       }
       Path path = Paths.get(fileName);
       try {
-        cs.submit(new FormatFileCallable(parameters, path, Files.readString(path), options));
+        String input = new String(Files.readAllBytes(path), UTF_8);
+        cs.submit(new FormatFileCallable(parameters, path, input, options));
         files++;
       } catch (IOException e) {
         errWriter.println(fileName + ": could not read file: " + e.getMessage());