// parent class BorderCrossing

import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Scanner;

public class BorderCrossing {

// private instance variables for origin, destination, validity of passport,
// traveler info, commercial purposes, crossing ID and time spent at customs
private String origin;
private String destination;
private boolean validPassport;
private Traveler traveler;
private boolean commercial;
private int crossingID;
private double timeCustoms;

// parametrized constructor for BorderCrossing object
// throws an exception if origin or destination are invalid
public BorderCrossing(String origin, String destination, boolean validPassport,
Traveler traveler, boolean commercial, int crossingID, double timeCustoms) throws CrossingException {
if(belongs(origin) && belongs(destination)) {
this.origin = origin;
this.destination = destination;
this.validPassport = validPassport;
this.traveler = traveler;
this.commercial = commercial;
this.crossingID = crossingID;
this.timeCustoms = timeCustoms;
}
else
throw new CrossingException("Invalid Country");
}

// helper method for checking if some country belongs to the list of countries
// (the list is read from the assigned text file)
private boolean belongs(String country) {
ArrayList<String> countries = new ArrayList<String>();
boolean result = false;
try {
File f = new File("countries.txt");
Scanner reader = new Scanner(f);
while (reader.hasNextLine()) {
String c = reader.nextLine();
countries.add(c);
   }
   reader.close();
} catch (FileNotFoundException e) {
   System.out.println("The source file with countries was not found!");
   e.printStackTrace();
}

for(String c: countries) {
if(c.toLowerCase().equals(country.toLowerCase()))
result = true;
}
return result;
}

// getter for the origin
public String getOrigin() {
return origin;
}

// getter for the destination
public String getDestination() {
return destination;
}

// getter for the passport
public boolean getPassport() {
return validPassport;
}

// getter for the traveler
public Traveler getTraveler() {
return traveler;
}

// getter for the commercial purposes
public boolean getCommercial() {
return commercial;
}

// getter for the crossing ID
public int getCrossingID() {
return crossingID;
}

// getter for the time spent at customs
public double getTimeCustoms() {
return timeCustoms;
}

// setter for the origin
// an exception will be thrown if origin is not from the given list of countries
public void setOrigin(String origin) throws CrossingException {

Tasks 1. Write a recursive method that removes a character from a...