What is a static import in java?

First lets understand what does "java import" does to your java program! Consider the java import statements: 1) import package.ClassA; 2) import package.*; Java statement (1) gives you a license to use ClassA inside the whole program without the package reference. That is you can use like ClassA obj = new ClassA(); or ClassA.getStatic(); Java statement (2) allows you to use all the java cla...

Explain the scope of JSP objects.

Scope of JSP objects: The availability of a JSP object for use from a particular place of the application is defined as the scope of that JSP object. Every object created in a JSP page will have a scope. Object scope in JSP is segregated into four parts and they are page, request, session and application. page 'page' scope means, the JSP object can be accessed only from within the same page...

Difference between Vector and ArrayList in java?

java.util.Vector came along with the first version of java development kit (JDK). java.util.ArrayList was introduced in java version1.2, as part of java collections framework. As per java API, in Java 2 platform v1.2,vector has been retrofitted to implement List and vector also became a part of java collection framework. All the methods of Vecto...

How many types of java variables are there?

Java variables can be categorized into the following seven types: Class Variable Instance Variable Array Component Variable Method Parameter Variable Constructor Parameter Variable Exception Handler Parameter Variable Local Variable 1) Class Variable A java class variable is a field declared using the keyword static within a java class, or with or without the keyword static wit...

Explain the methods used for session tracking.

Following answer is applicable irrespective of the language and platform used. Before we enter into session tracking, following things should be understood. What is a session? A session is a conversion between the server and a client. A conversion consists series of continuous request and response. Why should a session be maintained? When t...

What is a java marker interface?

Java marker interface has no members in it. Marker interface 'was' used as a tag to inform a message to the java compiler. Java Marker Interface Examples: java.lang.Cloneable java.io.Serializable java.util.EventListener Lets take the java.io.Serializable marker interface. It doesnot has any members defined it it. When a java class is to be serialized, you should intimate the java compile...