Skip to main content

Java Servlet

Servlet technology is used to create a web application (resides at server side and generates a dynamic web page).

Servlet technology is robust and scalable because of java language. Before Servlet, CGI (Common Gateway Interface) scripting language was common as a server-side programming language. However, there were many disadvantages to this technology. We have discussed these disadvantages below.

There are many interfaces and classes in the Servlet API such as Servlet, GenericServlet, HttpServlet, ServletRequest, ServletResponse, etc.

What is a Servlet?

Servlet can be described in many ways, depending on the context.

  • Servlet is a technology which is used to create a web application.
  • Servlet is an API that provides many interfaces and classes including documentation.
  • Servlet is an interface that must be implemented for creating any Servlet.
  • Servlet is a class that extends the capabilities of the servers and responds to the incoming requests. It can respond to any requests.
  • Servlet is a web component that is deployed on the server to create a dynamic web page.
Servlet

What is a web application?

A web application is an application accessible from the web. A web application is composed of web components like Servlet, JSP, Filter, etc. and other elements such as HTML, CSS, and JavaScript. The web components typically execute in Web Server and respond to the HTTP request.

CGI (Common Gateway Interface)

CGI technology enables the web server to call an external program and pass HTTP request information to the external program to process the request. For each request, it starts a new process.

CGI vs., Servlet

Disadvantages of CGI

There are many problems in CGI technology:

  1. If the number of clients increases, it takes more time for sending the response.
  2. For each request, it starts a process, and the web server is limited to start processes.
  3. It uses platform dependent language e.g. C, C++, perl.

Advantages of Servlet

Advantages of Servlet

There are many advantages of Servlet over CGI. The web container creates threads for handling the multiple requests to the Servlet. Threads have many benefits over the Processes such as they share a common memory area, lightweight, cost of communication between the threads are low. The advantages of Servlet are as follows:

  1. Better performance: because it creates a thread for each request, not process.
  2. Portability: because it uses Java language.
  3. Robust: JVM manages Servlets, so we don't need to worry about the memory leak, garbage collection, etc.
  4. Secure: because it uses java language.



Anurag Rana

Comments

Post a Comment

Popular posts from this blog

Data Warehousing - An Overview

Anurag Information Technology (IT) has historically influenced organizational performance and competitive standing. The increasing processing power and sophistication of analytical tools and techniques have put the strong foundation for the product called data warehouse. There are a number of reasons that any organization should consider a data warehouse, which can be the critical tool for maximizing the organization’s investment in the information it has collected and stored throughout the enterprise. IT managers need to understand the rationale and benefits of data warehouses because they may need to design and implement, or procure this kingpin of business intelligence. The data warehouses are supposed to provide storage, functionality and responsiveness to queries beyond the capabilities of today's transaction-oriented databases. Also data warehouses are set to improve the data access performance of databases. Traditional databases balance the requirement of data access w...
Post a Comment
Read more

Standard and Formatted Input / Output in C++

The C++ standard libraries provide an extensive set of input/output capabilities which we will see in subsequent chapters. This chapter will discuss very basic and most common I/O operations required for C++ programming. C++ I/O occurs in streams, which are sequences of bytes. If bytes flow from a device like a keyboard, a disk drive, or a network connection etc. to main memory, this is called   input operation   and if bytes flow from main memory to a device like a display screen, a printer, a disk drive, or a network connection, etc., this is called   output operation . Standard Input and Output in C++ is done through the use of  streams . Streams are generic places to send or receive data. In C++, I/O is done through classes and objects defined in the header file  <iostream> .  iostream  stands for standard input-output stream. This header file contains definitions to objects like  cin ,  cout , etc. /O Library Header Files There are...
Post a Comment
Read more

Normalization in DBMS: 1NF, 2NF, 3NF and BCNF in Database

Normalization   is a process of organizing the data in database to avoid data redundancy, insertion anomaly, update anomaly & deletion anomaly.  Anomalies in DBMS There are three types of anomalies that occur when the database is not normalized. These are – Insertion, update and deletion anomaly. Let’s take an example to understand this. Example : Suppose a manufacturing company stores the employee details in a table named employee that has four attributes: emp_id for storing employee’s id, emp_name for storing employee’s name, emp_address for storing employee’s address and emp_dept for storing the department details in which the employee works. At some point of time the table looks like this: emp_id emp_name emp_address emp_dept 101 Nikhil Kangra D001 101 Nikhil Kangra D002 123 Ashish Shimla D890 166 Rahul Pathankot D900 166 Rahul Pathankot D004 The above table is not normalized.  Update anomaly : In the above table we have two rows for employee Nikhil as he belongs ...
Post a Comment
Read more