高级自定义 > Info*Engine User's Guide (《Info*Engine 用户指南》) > Info*Engine JSP Pages > Task Webjects and JSP Pages
  
Task Webjects and JSP Pages
The Info*Engine task webjects give you a quick way to generate and manipulate information, as well as to manage your JSP pages. Info*Engine maintains the information that is generated in groups within its VDB, as discussed in Info*Engine Data Management. Task webjects do not return data to a displayable device such as a web browser. Any data generated by a task webject is returned as a group to the VDB.
Use task webjects along with display webjects to produce the data solution that your site requires. Both task and display webjects can be used on the same JSP page to generate and then display data.
Info*Engine provides the following types of task webjects:
Type
Description
GRP
Group webjects can create, compare, combine, sort, or otherwise manipulate groups.
MGT
Management webjects provide common functions that you can use to manage your JSP pages or tasks.
MSG
Message webjects can be used in conjunction with a third-party MOM for generic messaging functions and task queuing functions.
WES
Web Event Service (WES) webjects can be used in conjunction with a third-party MOM for handling Info*Engine events.
ACT
Action webjects are provided by adapters to perform actions such as creating, copying, and updating data in a data repository.
ADM
Administrative webject perform specific administrative functions, such as gathering simple statistics, or causing service properties to reload at runtime.
OBJ
Query webjects are provided by adapters to search external databases for objects that match specified criteria.
You can use group and management webjects on any JSP page or in any task with just the basic Info*Engine environment set up. To use message or Web Event Service webjects, your site administrator must have installed and configured a MOM and implemented the Info*Engine features that provide the environment required by the webjects.
In addition, you can create external custom webjects (EXT type) that provide custom solutions in either a JSP page or a standalone task.
The DisplayTable.jsp page example previously provided contains the following group webject:
<ie:webject name="Create-Group" type="GRP">
  <ie:param name="ELEMENT"
     data="name=myGroup2:email=xxx@xxx.com:address=PTC"/>
  <ie:param name="GROUP_OUT" data="newGroup2"/>
</ie:webject>
The result of executing the Create-Group webject is the “newGroup2” group, which has one element (row), with three attributes (columns):
name
email
address
myGroup2
xxx@xxx.com
PTC
Use the webject tag to code task webjects, as well as display webjects. In this example, the webject tag syntax includes both the beginning and ending webject tags. In the previous display webject example, only the beginning tag was needed. The ending webject tag is needed here because the Create-Group webject has two parameters that are nested inside the webject tag: ELEMENT and GROUP_OUT. These parameters are defined using param tags.
Administrative Webjects describes all group, management, message, and Web Event Service webjects. There are also task webjects used in the examples shown throughout the remaining sections on this topic.
The action and query webjects available to you are determined by which adapters have been installed at your site. For more information, see Adapter Webjects and JSP Pages.