Getting started with JSP built-in objects (2) "01" page, request

Built-in objects are the core of JSP, it can be said that built-in objects throughout the Web, even in the subsequent development is still frequently used.

The table in "JSP built-in object" 01 "describes the built-in objects in 9 that are really common to four: page, request, and response, session, application.

Each of these four built-in objects has its own purpose and method. But all have the same purpose: to accept parameters, there are the following property action methods:

So the four objects are different in that four built-in objects have four different properties operating range. I'm going to take a look at the four attribute ranges in detail.

What is an attribute range