The terminal does not allow me to type any values

package Exer6;

import java.io.*;
import java.util.*;
import java.net.*;

public class Exercise1 {

    public static void main(String[] args) {

        try {
            String[] split = null;
            String[] cpline = null;
            String[] IDNum = null;
            URL ReadUrl = new URL(args[0]);
            BufferedReader in = new BufferedReader(new InputStreamReader(
                    ReadUrl.openStream()));

            String line = in.readLine();

            while (line != null) {
                int i = 0;
                cpline[i] = line;
                i++;
            }

            while (line != null) {
                split = line.split(",");
                int i = 0;
                IDNum[i] = split[0];
                i++;
            }

            Scanner scan = new Scanner(System.in);
            System.out.println("Enter Users ID Number");
            String ID = scan.nextLine();

            for (int i = 0; i < IDNum.length; i++) {
                if (ID.equalsIgnoreCase(IDNum[i])) {
                    System.out.println(cpline[i]);
                }
            }

        } catch (Exception e) {
            e.getMessage();
        }
    }
}