i desperatly need help with figuring out this problem with my uni
assignment

i am creating a vehicle hire program, so far you can add cars, view
information on certain cars and add a customer. however when
displaying the information about a certain car if that car is on loan
i need to display the customers information. the problem i am having
is that the customer information is only being displayed when all of
the cars in the vector are set to onloan. any help would be useful


here is some of my code.

public void addCar(String make, String regNo, String colour,
int noOfDoors, double totalMileage, double recordedMileage) {
carVector.addElement(new Car(make, regNo, colour,
noOfDoors, totalMileage, recordedMileage));
}

public void findCar(String regNo) {
int i = 0;
while(i < carVector.capacity()) {
car = (Car)carVector.elementAt(i); //temp
if(regNo.equalsIgnoreCase(car.getRegNo())) {
car.setStatus();
vehicleDetails = new VehicleDetails
(car.getMake(), car.getColour(), car.getRegNo(), car.getNoOfDoors(),
car.getTotalMileage(), car.getRecordedMileage(), car.getStatus());
if(car.onLoan == true)
customerDetails = new Customer
(customer.getName(), customer.getLicenceNo(), customer.getVector());
}
i++;
}
}

//experimental
public void allocateCar(String name, int licenceNo, String regNo) {
customerVector.addElement(new Customer(name,
licenceNo, personalVector));
customer = (Customer)customerVector.elementAt(0);
int i = 0;
while(i < carVector.capacity()) {
car = (Car)carVector.elementAt(i);
if(regNo.equalsIgnoreCase(car.getRegNo())) {
car.onLoan = true;
car.setStatus();
personalVector.addElement(car);
//this will be removed
customerDetails = new Customer(customer.getName(),
customer.getLicenceNo(), customer.getVector());
}
i++;
//ideally needs error checking CAUSES NULLPOINTER EXCEPTION
}
}