What Are Implicit Objects Available to the JSP Page

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Implicit objects are the objects available to the JSP page. These objects are created by Web container and contain information related to a particular request, page, or application.

The JSP implicit objects are:

Application, config, exception, out, page, pageContext, request, response andsession.

In JavaServer Pages (JSP), there are several implicit objects available that can be used without explicitly declaring them. These objects provide functionality and information related to the request, response, session, application, and more. The commonly used implicit objects in JSP are:

  1. request: Represents the client’s request to the server. It encapsulates information such as parameters, headers, and attributes associated with the request.
  2. response: Represents the server’s response to the client. It allows you to set response headers and send content back to the client.
  3. out: An instance of the JspWriter class, which is used to send output to the client’s browser.
  4. session: Represents the user session. It allows you to store and retrieve session-specific information.
  5. application: Represents the servlet context or application scope. It allows you to store and retrieve global information that is accessible to all users of the application.
  6. config: Represents the servlet configuration. It provides access to initialization parameters specified in the deployment descriptor.
  7. pageContext: An instance of the PageContext class, which provides access to all the implicit objects.
  8. page: Refers to the current JSP page (this).
  9. exception: Represents any exception that occurs during the execution of the JSP page. It is used in error handling.

For example, you can use these implicit objects in your JSP page like this:

jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<html>
<head>
<title>Implicit Objects in JSP</title>
</head>
<body>
<h1>Request Parameter: <%= request.getParameter("paramName") %></h1>
<h1>Session Attribute: <%= session.getAttribute("attributeName") %></h1>
<!-- Other implicit objects can be used similarly -->
</body>
</html>

These implicit objects simplify the interaction with the underlying servlet infrastructure and allow developers to access various aspects of the request, response, and application state without explicitly declaring variables.