HttpServer error in reading buffer size via keyboard input - HELP

Question

I've written a simple HttpServer program that reads keyboard input to construct a buffer to copy the requested file into the socket's output stream. I've done the string-to-integer conversion using BufferedReader and parse.Int. However, when I go to use the int later in the program, I keep getting the message "variable b may not have been initialized." Can anyone tell me what's missing from the code below? Thanks.
private static void sendBytes(FileInputStream fis, OutputStream os)throws Exception
     //Construct a buffer via console input
     BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
     String str;
     int b;
          System.out.println("Enter desired buffer size or CTRL-C to break.");
     //Convert entry to an integer
     do
          str = br.readLine();
             try
               b = Integer.parseInt(str);
          catch(NumberFormatException e)
               System.out.println("Invalid entry.");
     while((str=br.readLine())!=null);
     //Construct a buffer
     byte[] buffer = new byte;
     int bytes = 0;
     //Begin timing HTML page delivery
     long start, end;
          System.out.println("Timing for Web page delivery");
     start = System.currentTimeMillis();
     //Copy requested file into the socket's output stream
          while((bytes = fis.read(buffer)) != -1)
          os.write(buffer, 0, bytes);

Answer 1

As the message suggests, what is missing is code to initialize the variable b. The first mention ("int b;") does not initialize it. The second mention ("b = Integer.parseInt(str);") only initializes it if no exception is thrown. So it's possible for b to be uninitialized when you actually try to use it.
What do you need to change? First you need to decide what's to be done if the keyboard input isn't a valid integer. Do you have a default value in mind? If so, put that where you declare the variable ("int b = 42;"). If not, just initialize the variable to zero ("int b = 0;").