title: What is the purpose of a no-arg constructor?
body: <p>I understand most of the code below. 
  I just don't understand the purpose of the no-arg constructors of Employee and Person since I get the same results when I delete them. I am new to java so I apologize if this is a dumb question. This is a code snippet for one of my classes.
  Any help will be appreciated.</p>
  
  <pre><code>public class TestEmployee {
      public static void main(String[] args) {        
          // Define some employees
          Employee president  = new Employee("Lucy", "President", 100000);        
          System.out.println(president);  
  
  
          Employee cto  = new Employee("Vincent", "Chief Tech Officer", 70000);       
          System.out.println(cto);    
      }
  }
  
  class Employee extends Person{
      // ADD YOUR CODE HERE!!!
      // Nothing above needs to change.
      private String jobTitle="Unknown";
      private int salary = 0;
  
      public Employee() {
  
      }
  
      public Employee(String name, String jobTitle, int salary) {
          super(name);
          this.jobTitle = jobTitle;
          this.salary = salary;
      }
  
      @Override
      public String toString() {
          return this.getName() + " is the " + jobTitle + " and makes $" + salary + " a year.\n";
      }
      // You need data fields, a constructor or two, and a to-string method
  }
  
  // IF YOU ALREADY HAVE THE PERSON CLASS IN YOUR WORKSPACE
  // YOU CAN DELETE THIS. OTHERWISE YOU'LL GET AN ERROR:
  // 'The type Person is already defined.'
  class Person {
      private String name = "Default Name";
  
      // No-arg Constructor
      public Person () {
      }
  
      public Person (String name){
          this.name = name;
      }
  
      // Getter method
      public String getName() {
          return name;
      }
  
      // Setter method
      public void setName(String newName) {
          if (!newName.equals("")) {
              name = newName;
          }
          else
              System.out.println("Can't change name. Empty names aren't allowed!");
      }
  
      public String toString() {
          return "Name: " + name + "\n";
      }
  }
  </code></pre>