What are the built-in objects for the JSP? What is the difference? __js

JSP has a total of the following 9 basic built-in components

1, Request object client requests, this request will contain the parameters from the Get/post request through it to understand the customer's needs, and then respond.

2, the response object to respond to customer requests for information

3. Session object It refers to a client-server conversation that starts with a webapplication from the client to the server until the client disconnects from the server.

4, out object It is an instance of the JspWriter class, is the output to the client commonly used objects

5, Page object it refers to the current JSP page itself, somewhat like the this pointer in the class, it is an instance of the Java.lang.Object class

6, Application object It realizes the sharing of data among users, and can store global variables. It starts at the start of the server until the server shuts down

7, exception object It is an exception object, when a page in the process of the exception occurred, the object is generated.

8, PageContext object It provides access to all objects and namespaces within the JSP page 9, config object It is in a Servlet initialization, the JSP engine to pass information to it