Can't figure out a compilation error for simple Java app
<p>This is the error I am getting: 
<strong>Error: The type Customer must implement the inherited abstract method java.lang.Comparable.compareTo(Customer)</strong></p>

<p>I'm comparing it to some lab work that I did and it looks exactly the same, yet that compiled just fine. I'm not sure what's going on here.</p>

<p>Here is the code segment in question which, incidentally, was written by my professor: </p>

<pre><code>class Customer implements Comparable&lt;Customer&gt;
{
 String name;
 double purchase;
 double rebate;

public Customer(String n, double p, double r)
{ name=n;
  purchase=p;
  rebate=r;
 } //end Constructor

 public Customer(String n)
 { 
  name=n;
 } //end Constructor

 public String toString()
 {
  return String.format("%-20s%10.2f%10.2f", name, purchase, rebate);
 }

 /*
  Here, define the method comparedTo of the Comparable
  interface so that an array of Customer objects can
  be sorted by customer name
 */
 public int comparedTo(Customer a)
{
return this.name.compareTo(a.name);
}   //end comparedTo

} //end class Customer
</code></pre>

<p>Oh, and here are the inclusions the professor included: </p>

<pre><code>import java.io.File;
import java.io.FileNotFoundException;
import java.util.Arrays;
import java.util.Comparator;
import java.util.Scanner;
</code></pre>

<p>Your help is greatly appreciated!</p>
