Using the compareTo(String) to alphabetize strings in an array?

Question

Basically I have an employees array that has commission, salary, and hourly employees. I need to display an alphabetized list of the employees. If the last names are the same the first names also need to be alphabetized. How do I go about doing this.

Answer 1

Arrays.sort(employees, new Comparator<Employee>() {
  public int compare(Employee a, Employee b) {
    int cmp = a.getLastName().compareTo(b.getLastName());
    if (cmp == 0) {
      cmp = a.getFirstName().compareTo(b.getFirstName());
    }
    return cmp;
  }
});

Or, using Guava to get something more readable and less bug-prone,

Arrays.sort(employees, new Comparator<Employee>() {
  public int compare(Employee a, Employee b) {
    return ComparisonChain.start()
      .compare(a.getLastName(), b.getLastName())
      .compare(a.getFirstName(), b.getFirstName())
      .result();
  }
});