Session Tracking

By default all web application are stateless web application that means web applications can not use first request data for second request.this is called stateless.
But we can use one of the following four session tracking techniques to make them "stateless"

                    1.Hidden form fields

                    2.Cookies

                    3.HttpSession with Cookies

                    4.HttpSession with url rewriting

Filters in Java

• Servlet filters are a new addition to the servlet 2.3 realized in Oct 2000
• Definition:

• Filters are java classes that can intercepts request from a client before they access a resource, manipulate request from clients, intercepts response from resource before they sent back to the client.

ServletListeners

• Listener is one of the most popular technologies used in the J2EE web application
• It is part of the Java Servlet as defined in Servlet 2.3 but they have their own specific functionalities.

Difference between Servlet and CGI

• Serverside web resource programs are generally dynamic web resource programs because they generate dynamic we pages when they are requested by browser.

Introduction about Servlet

• The Application that are specific to one computer and contains main method is called Standalone applications 

Servlet For You

This Servlet tutorial is also a good starting guide for the beginners. You will learn how to write Servlet, compile, configure on Tomcat, start server and test the Servlet. We will also explain how you can recompile and test the Servlet if there is any error or code modification is needed.

Servlet is used for developing server side programs for a web application based on JAVA. Servlet is based on request response model which can handle any type of request but Servlet also provides Http specific API to handle Http request more efficiently and easily.

Previously CGI was the means of providing dynamic content. CGI was platform dependent and needs to recompile the programs in the new operating system, it is process based. But Servlet is platform independent because of Java's platform independent feature and is thread based. Servlet are more advantageous over CGI in terms of features like Platform Independence, Performance, Extensibility and Security etc.

Servlet runs on JVM on the server and so safe and portable. Servlet do not require java in web browser unlike Applets.

JDBC Interview Questions

JDBC Objective Questions

See These Questions

Scrollable ResultSet

In Jdbc Programming we have two ResultSets They are
1)Non Scrollable/Sequential ResultSet
2)Scrollable ResultSet

Developing Flexible JDBC Application

In Industry level if we develop N number of JDBC applications which deals specific database and if project client want to change the database then the java programmer has to modify N number of  JDBC applications which is the time consuming process  and hence Industry is not recommended to develop a specific JDBC applications. But Industry is always recommended to develop flexible JDBC Application

Meta Data

Data about data is known as MetaData
In JDBC Application development we have 3 catagerious of metadata they are

Transfer Excel data to oracle

Steps to Transfer excel sheet data to oracle database

Dealing with Excel database

Ms-Excel is the confidential database used for representing financial information for generating balance shee

Dealing with MS-Access Database

We can access the data from MS-Access by using java application

Batch Processing

If a JDBC application contains multiple DML queries, to execute these queries our jdbc application requires n number of network round trips between jdbc application and database application which will reduces the performance

Stored Procedure in JDBC

it is highly recommended develop a JDBC application in such way that write separate logic for Java and write a separate logic for database. Database logic is nothing but stored procedures.

Group Function in JDBC

In Most of RDBMS Products we came across 5 aggregate functions they are

Type-4 Driver

Oracle corporation has developed their own driver in java language according to sun micro system specifications. the name of the oracle driver is oracle.jdbc.driver.OracleDriver

Dynamic Queries

A Static query is one in which the data is passed with in the itself

Steps to Develop First Jdbc Applications

To Write Standard JDBC Application we need to follow the following Sequence of steps.

Types of Drivers

To Deal with any database through our java program, first we must identify the specific JDBC Driver (oracle Driver) and that Driver must registered with DriverManagers class and whose fully Qualified name is 

JDBC For You

In Information Technology we have two types of application. they are
i. Non-persistent/ volatile application
ii. Persistent logic/ non-volatile application

Interview Question on core java for Freshers

1.what is difference between #include and import statement

Ans:#include makes the compiler to go the c/c++ library and copy the code in our program from header file. So program size will be increased and to compile that code waste of time. And memory will be wasted

Import statement makes the jvm to go the java standard library, execute the code there and it brings back only the results into our program. Here no code is copied and hence no waste of memory.

So import is an more efficient than #include