title: Why default constructor is required in a parent class if it has an argument-ed constructor?
body: <p>Why default constructor is required(explicitly) in a parent class if it has an argumented constructor  </p>
  
  <pre><code>class A {    
    A(int i){    
    }
  }
  
  class B extends A {
  }
  
  class Main {    
    public static void main(String a[]){
      B b_obj = new B();
    }
  }
  </code></pre>
  
  <p>This will be an error.</p>