What is the use of Marker interface, eventhough it has no methods? And how o control the actions occured by those interfaces?

Marker interfaces are understood by the JVM. The JVM takes care of how to deal with a class that implements that marker interface

An example of how Marker interfaces are resolved can be found at the link below: http://jdj.sys-con.com/read/36635.htm here is a snippet from the same link When you implement Serializable, you don't even have to implement any new methods because Serializable doesn't declare any. So then what good does implementing Serializable do? Serializable does not implement or declare a class's serializable behavior; the default implementation for that behavior is already implemented by ObjectOutputStream.defaultWriteObject() and ObjectInputStream.defaultReadObject(). (It would have just been easier to put this code in Object as default implementations of readObject(ObjectInputStream) and writeObject(ObjectOutputStream) that subclasses could override or extend.................

Here is another article on Marker Interface. http://www.anupsabbi.com/index.php?content=articles/java/marker_interfaces.html