Error - The constructor Level2Class(double) is undefined
<p>My code -  </p>

<pre><code>public abstract class Level1Class
{
  protected double num = 0.0D;  
  protected Level1Class(){}
  protected Level1Class(double num){this.num = num;}
  protected abstract methods A, B, C...etc //pseudocode !

}

public class Level2Class extends Level1Class
{
  //NO CONSTRUCTORS HERE
  //BUT, only implementation of methods A,B, C
} 

public class Tester
{
  Level2Class l2c = new Level2Class(10.0D); //This causes the compiler error ! 
}
</code></pre>

<p>Can someone tell me why I get this error. I know it will go if I create the necessary constructor in Level2Class. But, I want to know the reason.</p>
