Move from string to array but after that select by the first character (Record Type 1, 2, 5)

Question

I need your help, I am new in Java

I need to read a flat file with 5 different of records the way to differentiate each record is the first characters, after that I have the idea to move to an 5 different array to play with with the data inside.

example

120220502Name Last Name1298843984    $1.50
120220501other client  8989899889   $23.89
2Toronto372 Yorkland drive        1 year Ontario
512345678Transfer             Stove          Pay
522457839Pending              Microwave      Interactive

any help will quite appreciated

Answer 1

Break the problem into chunks. The first problem is reading the file:

try (BufferedReader reader = new BufferedReader(new FileReader("path/to/file"))) {
    parseData(reader); //method to do the work.
} catch (IOException e) {
    e.printStackTrace();
}

Then you need to decide what kind of record it is:

public void parseData(BufferedReader input) throws IOException {
    for (String line = input.readLine(); line != null; line = input.readLine()) {
        if (line.startsWith("1")) {
            parseType1(line);
        } else if (line.startsWith("2")) {
            parseType2(line);
        } else if (line.startsWith("5")) {
            parseType5(line);
        } else {
            throw new Exception("Unknown record type: " + line.charAt(0));
        }
    }
}

Then you'll need to create the various parseTypeX method to handle turning the text into usable chunks and then into classes.

public Type1Record parseType1(String data) {
    //create a Type1Record
    Type1Record record = new Type1Record();
    //split the string something like 
    String [] fields = data.split("\\s+");
    //Assign those chunks to the record
    record.setId(fields[0]);
    record.setFirstName(fields[1]);
    record.setLastName(fields[2]);
    record.setTotal(fields[3]); //if you want this to be a real number, you'll need to remove the $       
}

Repeat the process with the other record types. You'll likely need to group records together, but that should be easy enough.