Define JSP and explain the following:i) Tags ii) Variables iii) Objects

Define JSP and explain the following:
i) Tags ii) Variables iii) Objects

Answer:-

What is JSP?

JSP (JavaServer Pages) is a server-side technology used to create dynamic web content. It allows embedding Java code directly into HTML pages using special JSP tags. JSP files are compiled into servlets by the server and can interact with databases, session objects, and business logic.

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i) Tags in JSP

Tags in JSP are special syntactic constructs used to embed Java code, display content, or control behavior. There are several types:

Types of JSP Tags

Tag Type	Syntax	Purpose
Directive tag	<%@ ... %>	Gives instructions to the JSP compiler (e.g., imports, page settings)
Declaration tag	<%! ... %>	Declares variables or methods accessible throughout the JSP page
Scriptlet tag	<% ... %>	Contains Java code executed during page processing
Expression tag	<%= ... %>	Outputs the result of a Java expression
Action tag	<jsp:...>	Predefined tags for standard operations (e.g., <jsp:include> to include another file)

Example:

<%@ page language="java" %>
<%! int counter = 0; %>
<%
   counter++;
%>
<p>Page visited <%= counter %> times.</p>

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ii) Variables in JSP

Variables in JSP are used to store data temporarily during page processing. They can be:

Types of Variables:

Type	Scope	Declared In
Local variables	Inside methods or scriptlets	<% int x = 10; %>
Instance variables	In declaration tag	<%! int count = 0; %>
Implicit variables	Automatically provided by JSP engine	e.g., request, response

Example:

<%! int visits = 0; %>
<%
    visits++;
%>
<p>Total visits: <%= visits %></p>

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iii) Objects in JSP

JSP provides several implicit objects that you can use directly without declaring them. These objects provide access to request data, response control, session management, and more.

Common Implicit Objects

Object	Description
request	Represents the HTTP request
response	Represents the HTTP response
out	Sends output to the client
session	Manages user session data
application	Shares data across the whole application
config	Servlet configuration
pageContext	Accesses page-level data
page	Refers to the current JSP page (like this in Java)
exception	Available in error pages only

Example:

<p>Hello <%= request.getParameter("name") %></p>

If URL is hello.jsp?name=Kushal, the output will be:

Hello Kushal

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Summary

Concept	Description
Tags	Used to embed Java code and control JSP behavior
Variables	Store data temporarily within the page
Objects	Built-in references to request, response, session, etc.