Car sales: solution

The class Car

import java.io.*;

public class Car {

  private String model;
  private int year;
  private int km;
  private double price;

  public Car(String m, int y, int k, double p) {
    model = m;   year = y;   km = k;   price = p;
  }

  public String toString() {
    return model + ", year: " + year + ", km: " + km + ", price: " + price;
  }

  public String getModel() {
    return model;
  }

  public int getYear() {
    return year;
  }

  public int getKm() {
    return km;
  }

  public double getPrice() {
    return price;
  }

  public boolean equalTo(Car c) {
    return this.model.equals(c.model) &&
      this.year == c.year &&
      this.km == c.km &&
      this.price == c.price;
  }

  public static Car read(BufferedReader br) throws IOException {
    String s = br.readLine();
    if (s == null)
      return null;
    else
      return new Car(s, Integer.parseInt(br.readLine()),
                     Integer.parseInt(br.readLine()),
                     Double.parseDouble(br.readLine()));
  }
}

The class CarList

import java.io.*;

public class CarList {

  private String filename;

  public CarList (String fn) {
    filename = fn;
  }

  public int countNewCars()  throws IOException {
    FileReader fr = new FileReader(filename);
    BufferedReader br = new BufferedReader(fr);

    int count = 0;
    Car c = Car.read(br);
    while (c != null) {
      if (c.getKm() == 0)
        count++;
      c = Car.read(br);
    }
    br.close();
    return count;
  }

  public Car mostExpensiveCar() throws IOException {
    // this is the second alternative for opening a file for reading
    FileInputStream is = new FileInputStream(filename);
    InputStreamReader isr = new InputStreamReader(is);
    BufferedReader br = new BufferedReader(isr);

    double max = 0;
    Car cmax = null;
    Car c = Car.read(br);
    while (c != null) {
      if (c.getPrice() > max) {
        max = c.getPrice();
        cmax = c;
      }
      c = Car.read(br);
    }
    br.close();
    return cmax;
  }

  public void addCar(Car c) throws IOException {
    FileWriter fw = new FileWriter(filename, true); //open file in append mode
    PrintWriter pw = new PrintWriter(fw);

    pw.println(c.getModel());
    pw.println(c.getYear());
    pw.println(c.getKm());
    pw.println(c.getPrice());
    pw.close();
  }

  public void removeCar(Car c) throws IOException {
    File f = new File(filename);
    FileInputStream is = new FileInputStream(f);
    InputStreamReader isr = new InputStreamReader(is);
    BufferedReader br = new BufferedReader(isr);

    // this is the second alternative for opening a file for writing
    File ftemp = new File("cars-temporary.txt");
    FileOutputStream os = new FileOutputStream(ftemp);
    PrintWriter pw = new PrintWriter(os);

    Car curr = Car.read(br);
    while (curr != null) {
      if (!curr.equalTo(c)) {
        pw.println(curr.getModel());
        pw.println(curr.getYear());
        pw.println(curr.getKm());
        pw.println(curr.getPrice());
      }
      curr = Car.read(br);
    }
    br.close();
    pw.close();

    ftemp.renameTo(f);
  }
}