What is meant by JSP implicit objects? Explain different implicit objects provided by JSP briefly.

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 JSP IMPLICIT OBJECTS

There are several objects that are automatically available in JSP called implicit objects. These objects are available to developers on each page and developers can call them directly without being explicitly declared. JSP Implicit Objects are also called pre-defined variables. There are nine implicit objects defined in JSP container. These objects are described below:

out an object- This object is used for writing any data to the buffer. It is the object of the Print Writer class.

request object- This is the object of HttpServletRequest class. This object is normally used in looking up parameter values and cookies.

response object- This is the object of HttpServletResponse class. Through this object, the JSP programmer can add new cookies or date stamps, HTTP status codes, etc.

config object- The config object is an instantiation of ServletConfig class. This object can be used to get an initialization parameter for a particular JSP page.

exception object- exception is an implicit object of Throwable class. This object can be used to print the exception.

Application object- It is an instance of ServletContext class and is created only once by the web container when the application or project is deployed on the server. This object can be used to get the initialization parameters from the configuration file (web.xml).

Session object- session is an implicit object of type HttpSession. The Java developer can use this object to set,get or remove attributes or to get session information.

Page object- page is an implicit object of type Object class. This object is assigned to the reference of auto-generated servlet class.

pageContext object- pageContext is an implicit object of type PageContext class. The pageContext object can be used to set, get or remove attribute from object scopes.

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