JSP的内置(隐含)对象及EL表达式的内置(隐含)对象

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    JSP中的内置对象一共有九个, 由于有的不太常用, 所以总是记不住, 从Sun公司的网站上找到的PDF文档, 把这一部分放在这里, 以备随时查用:
    JSP九个内置对象:
Implicit Objects for Scriptlets
(JSP Scriplets中的隐含对象)
Type
(对应类型)
Scope
(范围)
Some Useful Methods (see class or interface for others)
(常用的方法)
1
request
Subclass of javax.servlet.ServletRequest
Request
getAttribute, getParameter, getParameterNames, getParameterValues, setAttribute
2
response
Subclass of javax.servlet.ServletResponse
Page
Not typically used by JSP page authors
3
pageContext
javax.servlet.jsp.PageContext
Page
findAttribute, getAttribute, getAttributesScope, getAttributeNamesInScope, setAttribute
4
session
javax.servlet.http.HttpSession
Session
getAttribute, getId, setAttribute
5
application
javax.servlet.ServletContext
Application
getAttribute, getMimeType, getRealPath, setAttribute
6
out
javax.servlet.jsp.JspWriter
Page
clear, clearBuffer, flush, getBufferSize, getRemaining
7
config
javax.servlet.ServletConfig
Page
getInitParameter, getInitParameterNames
8
page
java.lang.Object
Page
Not typically used by JSP page authors
9
exception
java.lang.Throwable
Page
getMessage, getLocalizedMessage, printStackTrace, toString

JSP十一个用于EL表达式的隐含(内置)对象:
Implicit Objects for EL
Expressions
用于EL表达式的隐含对象
Type
类型
Description
具体说明
pageContext
javax.servlet.jsp.PageContext
The context for the JSP page. Provides access to various objects, including servletContext, session, request, and response.
pageScope
java.util.Map
Maps page-scoped variable names to their values.
requestScope
java.util.Map
Maps request-scoped variable names to their values.
sessionScope
java.util.Map
Maps session-scoped variable names to their values.
applicationScope
java.util.Map
Maps application-scoped variable names to their values.
param
java.util.Map
Maps a request parameter to a single String parameter value (obtained by calling ServletReqwuest.getParameter(String name)).
paramValues
java.util.Map
Maps a request parameter name to an array of String values for that parameter name (obtained by calling ServletRequest.getParameterValues(String name)).
header
java.util.Map
Maps a request header name to a single String header value (obtained by calling ServletRequest.getHeader(String name)).
headerValues
java.util.Map
Maps a request header name to an array of String values for that header (obtained by calling ServletRequest.getHeaders(String)).
coookie
java.util.Map
Maps a cookie name to a single Cookie object. Cookies are retrieved according to the semantics of HttpServletRequest.getCookies(). If the same name is shared by multiple cookies, an implementation must use the first one encountered in the array of Cookie objects returned by the getCookies() method. However, the ordering of cookies is currently unsspecified in the Servlet specification.
initParam
java.util.Map
Maps a context initialization parameter name to a String parameter value (obtained by calling ServletContext.getInitparameter(String name)).


本文来自ChinaUnix博客，如果查看原文请点：http://blog.chinaunix.net/u/15221/showart_1660215.html