Why compilation error is giving in this java code? : <p>I was trying to compile the code and it shows a compilation error. Can anyone help me out to understand what is wrong in the code? I guess there should be a default constructor inside Mammal class but why?</p>

<pre><code>class Mammal {
 public Mammal(int age) {
 System.out.print("Mammal");
 }
 }
 public class Platypus extends Mammal {
 public Platypus() {

 System.out.print("Platypus");
 }
 public static void main(String[] args) {
    new Mammal(7);   //Compilation Error
 }
}  
</code></pre>
