Not sure what problem you are facing... but one obvious thing i spotted is that you are having a statement after the break; You might have got 'Unreachable code' error. If that's not your issue, could you elaborate on your problem? Also, could you please correct indentation?
The code you have given have following problems:
1. There is no java object type called "character". Might be you wanted "Character".
2. You have not defined what is "input" variable on line 28.
3. You have not defined "temp", "cel", "df" before you used them. You can not initiate them whenever you want. (Happened for "df")
4. This whole line has formatting error:
JOptionPane.showMessageDialog(null, (cel + " degrees in Celsius is " + df.format (f) + " degrees in Fahrenheit." "ConvertTemp05");
5. What is "fht"?????????????
Please fix these problems first, the program should work. (I am wondering how did you get any kind of output.. the code should not compile even)... Good luck.. :)