Example

class ClassA implements Runnable {
ClassA () {
}

}

Solution
In the given example "Class A" is implementing the interface 'Runnable'. But it does not have a run() method. Every class implementing the 'Runnable' interface must have "run" method with no argument and return type 'void'



class ClassA implements Runnable {
ClassA () {
}

synchronized public void run() {
}
}