title: Are all abstract methods in java declared with void return type?
body: <p>Must all abstract methods in java be declared with void return type? 
  i.e. </p>
  
  <pre><code>public abstract void myMethod();
  </code></pre>
  
  <p>instead of </p>
  
  <pre><code>public abstract myMethod();
  </code></pre>
  
  <p>What happens when the method is not declared with void return type?</p>
  
  <p>I suppose that a method declaration as below is also wrong due to the existence of the 'scope' symbols.</p>
  
  <pre><code>public abstract void myMethod() {}
  </code></pre>
  
  <p>Kindly clarify my doubts, as I am still a beginner in this area. </p>