JSP Implicit Objects are the Java objects which are directly called without explicit declaration that the JSP Container makes available to developers. JSP Implicit Objects are also called pre-defined variables.
There are nine Implicit Objects supported by JSP which are as follows:
|out||PrintWriter object used to send output to the client.|
|request||HttpServletRequest object associated with the request coming from client.|
|response||HttpServletResponse object associated with the response to the client.|
|session||HttpSession object associated with the request.|
|application||ServletContext object associated with application context.|
|config||ServletConfig object represents configuration details associated with the page.|
|pageContext||This is the object of class PageContext.|
|page||This is the object of class Object.|
|exception||This is the object of Throwable class.|
The out object is an instance of a javax.servlet.jsp.JspWriter object that is used to send content in a response. The JspWriter object is instantiated differently depending on whether the page is buffered or not. Buffering can be easily turned off by using the buffered='false' attribute of the page directive. The JspWriter object contains some methods as the java.io.PrintWriter class. However, JspWriter has some additional methods designed to deal with buffering. Unlike the PrintWriter object, JspWriter throws IOExceptions.
Following are the methods invoking by the out object.
|out.print()||Print a data type value|
|out.println()||Print a data type value then terminate the line with new line character.|
|out.flush()||Flush the stream.|