Operation attribute domain object JavaWeb_
Property and related methods :
1) method
Object getAttribute (String name): Gets the specified property
Enumeration getAttributeNames (): Gets Enumeration object names of all the properties of the composition
removeAttribute (String name): Removes the specified attribute
void setAttribute (String name, Object o): Set Properties
2) pageContext, request, session, application objects have these methods!
The four objects are also called domain objects
pageContext: scope attribute is limited to the current JSP page
request: attribute scope is limited to the same request
session: scope is limited to a session attribute: browser open until closed (not fail during the session)
application: current scope is limited to WEB application properties, the maximum range is the range of action of the properties, as long as a set properties in a JSP or Servlet elsewhere and may be acquired to