What is the task of the Listener interface? Write a socket program for a file server that makes a collection of files available for transmission to clients. When a client connects to the server, the server first reads a one-line command from the client. The command string can be of the form 'GET <filename>', where <filename> is a file name. The server checks whether the requested file actually exists. If so, it first sends the word 'OK' as a message to the client. Then it sends the contents of the file and closes the connection. Otherwise, it sends 'ERROR' to the client as message and closes the connection. Assume that there is no sub directories.[10]

Differentiate between path and class path in Java. When do you prefer anonymous inner class? Consider the following program and answer the given questions. 1) Name the list of class file created after compiling above program 2) Rewrite the above program using for loop[10]

What are the tasks of sliders and scroll pane? Explain any four types of layout manager.[10]