Question

I’m having a problem, I’m using a text file that has over a million lines of numbers. the data is in the format below, some lines have 3 pieces of data while others have only 2.
Each time the file gets to the data with only 2 bits, it seems to throw a null error (I’m using Try/catch to read the input stream)

If I remove the value 3 tokenizer then the program runs to the end.
Do I need to put an if statement to check if there is another token after the 2nd line? if so – how??

            while ((getLine = br.readLine()) != null)   {
              StringTokenizer tokenizer = new StringTokenizer(getLine);
              String Value1 = tokenizer.nextToken();
              String Value2 = tokenizer.nextToken();
              String Value3 = tokenizer.nextToken();
            //Does some more things
            }

The data

    11      22      33
    44      55      
    77      88      99
    10      11
    13      14
    16      17      18

Answer 1

You will have to check that there are still tokens in the tokenizer. You can do it like this:

String Value3 = tokenizer.hasMoreTokens() ? tokenizer.nextToken() : null;

Which will set Value3 to null if there is no 3rd token. You might want to instead set it to the empty string.

The alternative is to use getLine.split("\\s+"), which will return an array of tokens. If there are only 2 values, the array will be of length 2. So be careful when attempting to read the 3rd value, which might not be present.