title: Puzzling explanation on abstraction vs interface in java doc
body: <p>In java document, it is said :</p>
  
  <blockquote>
    <p>Unlike interfaces, abstract classes
    can contain fields that are <strong>not</strong>
    static and final, and they can contain
    implemented methods.</p>
  </blockquote>
  
  <p>Is that a correct text? that <strong>not</strong> part confuses me because interfaces don't have <code>static</code> or <code>final</code> fields, right?</p>
  
  <p>Source : <a href="http://download.oracle.com/javase/tutorial/java/IandI/abstract.html" rel="nofollow">http://download.oracle.com/javase/tutorial/java/IandI/abstract.html</a></p>
  
  <p>Thanks. </p>
  
  <p><strong>Edit :</strong></p>
  
  <pre><code>public interface GroupedInterface extends Interface1,
                                          Interface2, Interface3 {
  
     // constant declarations
     double E = 2.718282;  // base of natural logarithms
  
     // method signatures
     void doSomething (int i, double x);
     int doSomethingElse(String s);
  
  }
  </code></pre>
  
  <blockquote>
    <p>An interface can contain constant
    declarations in addition to method
    declarations. All constant values
    defined in an interface are implicitly
    public, static, and final. Once again,
    these modifiers can be omitted.</p>
  </blockquote>