JSP implicit objects

Every JSP file has 9 implicit object which you can use directly without being declared.
Implicit objects are the objects that are available for the use in JSP documents without being declared first. These objects are parsed by the JSP engine and inserted into the generated Servlet.
JSP implicit objects are as below:

Implicit object	Scope	comment
request	Request	request
response	Page	response
pageContext	Page	page environment
session	Session	session
application	Application	same as ServeletContext
out	Page	Writing to the outputstream
config	Page	same as ServeletConfig
page	Page	this pasge's Servlet
exception	Page	exception created on this page

Note: If you have your own object defined with same name as the implicit Object, then Implicit objects take precedence over your object. So, avoid to use implicit object name as your own object. 

JSP Life cycle

Any Java server Page or JSP have below given life cycle phase

• Pre-translated: Before the JSP file has been translated and compiled into the Servlet. In this step, any JSP file first converted into java file(it parse all jsp content and generate Servlet file)
• Translated: The JSP file has been translated and compiled as a Servlet. In this phase Servet created in previous step has compiles and converted into class file)
• Initialized: Prior to handling the requests in the service method the container calls the jspInit() to initialize the Servlet. It is called only once per Servlet instance.
• Service: Services the client requests. Container calls this method for each request.
• Destroy: The Servlet instance is out of service. The container calls the jspDestroy() method.