What implicit internal objects and methods exist on a…

Implicit objects on a JSP page:

request: Represents the HTTP request from the client. Type: javax.servlet.http.HttpServletRequest.
response: Represents the HTTP response to be sent to the client. Type: javax.servlet.http.HttpServletResponse.
out: Object for writing content to the response output stream. Type: javax.servlet.jsp.JspWriter.
session: Represents the user's session. Type: javax.servlet.http.HttpSession.
application: Represents the web application context. Type: javax.servlet.ServletContext.
pageContext: Represents the context of the current JSP page. Type: javax.servlet.jsp.PageContext. Contains methods to access other implicit objects and attributes with different scopes (page, request, session, application).
config: Represents the servlet configuration for the JSP page. Type: javax.servlet.ServletConfig.
page: Represents an instance of the servlet generated from the JSP page. Type: java.lang.Object (usually an instance of a servlet implementing javax.servlet.jsp.HttpJspPage). Rarely used, mainly for calling _jspService(HttpServletRequest, HttpServletResponse).
exception: Represents an exception if the page is an error page. Type: java.lang.Throwable. Available only on pages with the directive <%@ page isErrorPage="true" %>.

Implicit methods available in scriptlets (<% ... %>) and expressions (<%= ... %>):

These methods are part of the generated servlet and are available directly in scriptlets and expressions without explicit reference to the object. Essentially, they are methods of the base class or interfaces implemented by the generated servlet.

getServletConfig(): Returns the config object.
getServletContext(): Returns the application object.

Other methods of the servlet's base class (e.g., getServletInfo(), init(), destroy()), although present in the generated servlet, are usually not used directly in JSP scriptlets or expressions.

Example of using implicit objects:

// Getting a parameter from the request
String username = request.getParameter("username");

// Writing to the output stream
out.println("Hello, " + username + "!");

// Setting a session attribute
session.setAttribute("loggedIn", true);

// Getting an application context attribute
Object counter = application.getAttribute("visitCount");

// Forwarding the request to another page
request.getRequestDispatcher("anotherPage.jsp").forward(request, response);

What implicit internal objects and methods exist on a JSP page?