Driver.java

import java.io.*;
import java.util.*;

public class Driver {
  public static void main(String[] args) {
      Greeter g,g2;
      String result;
      g = new Greeter();
      g.setGreeting("Hello");
      g2 = new Greeter();
      g2.setGreeting("How are you doing");
      result = g.greet("Tom");
      System.out.println(result);
      result = g2.greet("Sara");
      System.out.println(result);

  }
}