Trouble with importing files

Question

ZIPCODE, CITY, STATE, LATITUDE, LONGITUDE
ZIPCODE, CITY, STATE, LATITUDE, LONGITUDE

I'm trying to make this able to open a text file with addresses formatted as such, Create a loop that instantiates a new ZipCode object with the five perameters in order, and then adds that object to ArrayList myZips.

I have a feeling that at least my delimiters are wrong.

public void readZipCodeData(String filename){

Scanner inFS = null; 
FileInputStream fileByteStream = null;

try{
    // open the File and set delimiters
    fileByteStream = new FileInputStream(filename);
    inFS = new Scanner(fileByteStream);
     inFS.useDelimiter(", *");

    // continue while there is more data to read
    while(inFS.hasNext()) {

        // read five data elements
        int zipCode  = inFS.nextInt();
        String city  = inFS.next();
        String state = inFS.next();
        double latitude  = inFS.nextDouble();
        double longitude = inFS.nextDouble();
        ZipCode z1 = new ZipCode(zipCode, city, state, latitude, longitude);
        myZips.add(z1);
    }
    fileByteStream.close();

    // Could not find file
    }catch(FileNotFoundException error1) {
        System.out.println("Failed to read the data file: " + filename);
    // error while reading the file                      
    }catch(IOException error2) {
        System.out.println("Oops! Error related to: " + filename);
}

}

Everytime I try running it as is it gives me a
java.util.InputMismatchException: null (in java.util.Scanner) error on the double longitude line. Any ideas?

woops, it cut that off, just a sec – David Nov 12 '15 at 04:16 — David, Nov 12 '15 at 04:16

score 0 · Accepted Answer · edited May 23 '17 at 11:59

I'm not familiar with Scanner for input, but rather BufferedReader. I find it simple to use, and I hope this solution works for you:

Charset charset = Charset.forName("US-ASCII");
try (BufferedReader reader = Files.newBufferedReader(filename, charset)) {
    String line = null;
    while ((line = reader.readLine()) != null) {

        // THIS IS THE CODE FOR EVERY LINE
        String[] data = line.split(", ");
        int zipCode = Integer.parseInt(data[0]);
        String city = data[1];
        String state = data[2];
        double latitude = Double.parseDouble(data[3]);
        double longitude = Double.parseDouble(data[4]);
        ZipCode z1 = new ZipCode(zipCode, city, state, latitude, longitude);
        myZips.add(z1);

    }
} catch (IOException x) {
    System.err.format("IOException: %s%n", x);
} catch (NumberFormatException x) {
    System.err.format("NumberFormatException: %s%n", x);
}

In this example, I read a whole line with BufferedReader.readLine(), and manually parse it using String.split() and Integer.parseInt() / Double.parseDouble(). It's more intuitive, and it works!

See working example here.

Because of the comment below, I guess I cannot suggest the answer above. However, there are two potential problems I see:

You might have not put in a double in the input file. Simple, honest mistake.
Or, by this SO answer, your locale may be set wrong. In some places, they use a , for decimal point instead of . Try switching these around.

My teacher is very strict on using the code provided to you. If I used that, even if it was correct, she would go ape shit. Dunno why — David, Nov 12 '15 at 04:25
@David maybe you can look at the example I provided? It might give you ideas. Because you didn't post your whole code, there might be errors elsewhere. — Jonathan Lam, Nov 12 '15 at 04:30
The only thing I can think of that's wrong is the input -- maybe you didn't input a double? — Jonathan Lam, Nov 12 '15 at 04:31
I'm glad I helped, but what is the new error / exception now? — Jonathan Lam, Nov 12 '15 at 04:51
I need to figure out why the try is catching on }catch(FileNotFoundException error1) — David, Nov 12 '15 at 05:01

gonzo · Answer 2 · 2015-11-12T04:38:55.030

Try something like this. Instead of parsing one field at a time, grab the whole line, turn it into an array of String using your delimiter , then parse to int/double. Scanner.nextLine() grabs the whole line for you.

try{
    // open the File and set delimiters
    fileByteStream = new FileInputStream(filename);
    inFS = new Scanner(fileByteStream);


        // read five data elements
            String[] data = inFS.nextLine().split(", ");
            int zipCode = Integer.parseInt(data[0]);
            String city = data[1];
            String state = data[2];
            double latitude = Double.parseDouble(data[3]);
            double longitude = Double.parseDouble(data[4]);
        ZipCode z1 = new ZipCode(zipCode, city, state, latitude, longitude);
        myZips.add(z1);

Trouble with importing files

2 Answers2