No abstract class cannot be instantiated i.e you cannot create a new object of this class No, an abstract class cannot be instantiated in Java. An abstract class is a class that is declared with the abstract keyword. It may have abstract methods (methods without a body) that must be implemented by its subclasses. Abstract classes cannot be instantiated on their own because they may contain incomplete or abstract methods, and it doesn’t make sense to create objects of an…

Read More Read More

: A class can have a block of initializer code that is simply surrounded by curly braces and labeled as static e.g. Code: public class Demo{ static int =10; static{ System.out.println(�Hello world�); } } And this code is executed exactly once at the time of class load In Java, a static initializer block is a block of code within a class that is executed only once when the class is loaded into the Java Virtual Machine (JVM). It is used…

Read More Read More

?– Every computer connected to a network has an IP address. An IP address is a number that uniquely identifies each computer on the Net. An IP address is a 32-bit number. In Java, InetAddress is a class that represents an Internet Protocol (IP) address. It is part of the java.net package and provides methods for working with IP addresses. The InetAddress class can be used to create instances representing both IPv4 and IPv6 addresses. Here’s a brief overview of…

Read More Read More

rebind() of the Naming class(found in java. rmi) is used to update the RMI registry on the server machine. Naming. rebind(”AddSever”, AddServerImpl); lookup() of the Naming class accepts one argument, the rmi URL and returns a reference to an object of type AddServerImpl. I’m sorry, but there seems to be a misunderstanding. As of my last knowledge update in January 2022, there are no rebind() and lookup() methods in the Naming class in Core Java. In Java, the Naming class…

Read More Read More

?– (1) Request Lifetime: Using this technique to pass beans, a request dispatcher (using either “include” or forward”) can be called. This bean will disappear after processing this request has been completed. Servlet: request. setAttribute(”theBean”, myBean); RequestDispatcher rd = getServletContext(). getRequestDispatcher(”thepage. jsp”); rd. forward(request, response); JSP PAGE:<jsp: useBean id=”theBean” scope=”request” class=”. . . . . ” />(2) Session Lifetime: Using this technique to pass beans that are relevant to a particular session (such as in individual user login) over a…

Read More Read More

Yes, a lock can be acquired on a class. This lock is acquired on the class’s Class object. Yes, in Java, it is possible to acquire a lock on a class. In Java, every class and object has an associated lock, also known as a monitor. This lock is used to control access to the critical section of code to ensure that only one thread can execute the code block at a time. To acquire a lock on a class, you can…

Read More Read More