Getting started with JSP built-in objects (1) Overview of built-in objects

JSP built-in objects can be said to have been exposed to the core of the JSP part of the. In fact, we have been exposed to this aspect of knowledge before, we remember that when the parameters of the previous acceptance of a request.getparameter (); Yes, this is one of the methods in the object of the built-in object we are talking about.

JSP built-in objects:

In the JSP, has been specifically for the user's use of a number of built-in objects, the so-called built-in mainly refers to all the objects no longer by the user's own instantiation of the operation of the object, but can be used directly.

For example, the previous study request, which has a method of accepting parameters, public string getparameter (string paramname), is actually a built-in object for the request itself.

The Web container prepares these songs for users with built-in objects.

The above picture shows a list of 9 built-in objects and describes the type and role of each object, and the request we learned before is just one of the built-in objects.

In fact, we often use only the first 5 kinds of objects, the latter 4 are not commonly used.

Method query:

Each of the built-in objects has a method for each object, and here you notice the Query method's matters. For those of you who are familiar with Java SE, you should know that querying Java methods is queried in the Java API, and here is what we call the query to the Java Servlet API, which is an inquiry document for Java EE. These two API documents are not the same as the two API documents.

For each of the built-in objects of the use and role, I will and you in the next study together to explore

This article is from the "Zhao Yuqiang blog" blog, please be sure to keep this source http://zhaoyuqiang.blog.51cto.com/6328846/1129714