What are default methods in Java?

The default keyword was introduced in Java 8 to solve compatibility issues. There were issues in Java’s earlier versions with interfaces only consisting of abstract methods, i.e., the method’s implementation was provided in a separate class. However, default brings up another issue.

Suppose an interface named Educative exists and the Courses class implements the interface. If the programmer wants to add a feature to the Educative interface along with its implementation, Java 8 will allow it.

interface Educative 
{ 
    // abstract method 
    public void printCourse(int courseCode); 
  
    // default method 
    default void feature() 
    { 
      System.out.println("Default Method Executed"); 
    } 
} 
  
class Courses implements Educative 
{ 
    // implementation of square abstract method 
    public void printCourse(int courseCode) 
    { 
        System.out.println(courseCode); 
    } 
  
    public static void main(String args[]) 
    { 
        Courses programming = new Courses(); 
        programming.printCourse(101); 
        // default method called
        programming.feature();
    } 
}

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