TechFundu

 

What is the difference between JSP and Servlets ?

JSP is used mainly for presentation only. A JSP can only be HttpServlet that means the only supported protocol in JSP is HTTP. But a servlet can support any protocol like HTTP, FTP, SMTP etc.

What is the difference between custom JSP tags and beans?

Custom JSP tag is a tag you defined. You define how a tag, its attributes and its body are interpreted, and then group your tags into collections called tag libraries that can be used in any...

Q1. How could Java classes direct program messages to the system console, but error messages, say to a file?
A. The class System has a variable out that represents the standard output, and the variable err that represents the standard error device. By default, they both point at the system console. This how the standard output could be re-directed:
Stream st = new Stream(new FileOutputStream(”output.txt”));
System.setErr(st); System.setOut(st);

Q2. What’s the difference between an...

Is “abc” a primitive value? – The String literal “abc” is not a primitive value. It is a String object.What restrictions are placed on the values of each case of a switch statement? – During compilation, the values of each case of a switch statement must evaluate to a value that can be promoted to an int value.

 What modifiers may be used with an interface declaration? – An interface may be declared as public or abstract.Is a class a subclass of itself? – A class is a subclass...

What are the types of messaging? – There are two kinds of Messaging. Synchronous messaging involves a client that waits for the server to respond to a message. Asynchronous messaging involves a client that does not wait for a message from the server. An event is used to trigger a message from a server.What is publish/subscribe messaging? – With publish/subscribe message passing the sending application/client establishes a named topic in the JMS broker/server and publishes messages to this...