Question

I have a textfile containing users’ information, in row form separated with commas. I’ve used a combination of experimenting and research to try and separate each row into individual pieces of information (by using the split function) which can be stored in the array, and then searched against. With the code I have each name and username in the textfile gets repeated 4 times each, how I don’t understand. All i’ve managed to do is confuse myself further, but all I need is to pull each row from the textfile, split it into its 4 separate pieces of information and store them in memory in some way to search against. The code i have is;

package assignment;


import java.io.*;

public class readUser {
public void read()
{
    try{

        FileInputStream propertyFile = new FileInputStream("AddUser.txt");

        DataInputStream input = new DataInputStream(propertyFile);
        BufferedReader reader = new BufferedReader(new InputStreamReader(input));

        String line;

        while ((line = reader.readLine()) != null) {

            String[] items = line.split(",");
            String[][] usersArray = new String [5][2];
            int i;
            for (String item : items) {

                for (i = 0; i<items.length; i++){
                    if (i == 0) {
                        System.out.println("Name: " + items[i]);
                    } else if (i == 1) {
                        System.out.println("Username: " + items[i]);


                }
            }
            }
            //System.out.println(line);



        }
        input.close();
    }
    catch (Exception e){

        System.err.println("Error: " + e.getMessage());
    }
        }

}

Thanks for any advice on this

Answer 1

Take a look at the break-down of your code and the problem becomes clear:

for each line in property file (while loop):
    for each item in line:
        for each item in line:
           if item 0 print username
           else if item 1 print username
           endif
        end loop
     end loop
end loop

Your code is basically iterating over the list of items twice. Keep in mind that in Java the following two code snippets are equivalent — in that they both iterate over the values of an array or collection.

A

for (String item : items) {...}

B

for (int i = 0; i < items.length; i++) {
    String item = items[i];
    ....
}