What is the difference between this() and super()?

this() can be used to invoke a constructor of the same class whereas super() can be used to invoke a super class constructor.

In Java, this() and super() are both used to invoke constructors, but they are used in different contexts and have different purposes:

1. this():
   • It is used to invoke the current class constructor.
   • It is often used to invoke one constructor from another within the same class.
   • It cannot be used to invoke a constructor from a superclass.

   Example:

   java

   public class MyClass {
private int value;// Parameterized constructor
   public MyClass(int value) {
   this.value = value;
   }

   // Default constructor that invokes the parameterized constructor using this()
   public MyClass() {
   this(10); // invoking the parameterized constructor
   }
   }

2. super():
   • It is used to invoke the constructor of the immediate superclass (the parent class).
   • It is often used when a subclass wants to call a constructor of its superclass.
   • If used, it must be the first statement in the subclass constructor.

   Example:

   java

   public class SubClass extends SuperClass {
private int subValue;// Parameterized constructor in the subclass
   public SubClass(int subValue) {
   super(); // invoking the constructor of the superclass
   this.subValue = subValue;
   }
   }

In summary:

• this() is used to invoke a constructor within the same class.
• super() is used to invoke a constructor from the immediate superclass.
• Both this() and super() must be the first statement in a constructor if they are used.