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super [Java]

Like C++, Java automatically invokes the base class' constructor if a derived class is created:
Super_M.java
class Super_B {
  Super_B() {
    System.out.println("CTor Super_B");
  }
}

class Super_D extends Super_B {
  Super_D() {
    System.out.println("CTor Super_D");
  }
}

public class Super_M {
  public static void main(java.lang.String args[]) {
    Super_D d = new Super_D();
  }
}
If this program is run, it prints: 
CTor Super_B
CTor Super_D
The call to the base class can explicitely be stated with super:
Super_Q.java
class Super_B {
  Super_B() {
    System.out.println("CTor Super_B");
  }
}

class Super_D extends Super_B {
  Super_D() {
    super();
    System.out.println("CTor Super_D");
  }
}

public class Super_Q {
  public static void main(java.lang.String args[]) {
    Super_D d = new Super_D();
  }
}
If this program is run, it prints: 
CTor Super_B
CTor Super_D