JSP command label

Action commands in JSP include, forward, usebean, getproperty, setproperty, and plugin.

I. include commands

<JSP: Include> the tag indicates a static or dynamic file.

Syntax:
<JSP: Include page = "path" Flush = "true"/>
Or
<JSP: Include page = "path" Flush = "true">
<JSP: Param name = "paramname" value = "paramvalue"/>
</Jsp: Include>

Note:
1. Page = "path" is a relative path or a relative path expression.
2. Flush = "true" must be set to true. The default value is false.
3. The <JSP: param> clause allows you to pass one or more parameters to a dynamic file. You can also use multiple <JSP: param> to pass multiple parameters to a dynamic file.

Ii. Forward Command

<JSP: Forward> the tag indicates redirecting a static html/JSP file or a program segment.

Syntax:
<JSP: Forward page = "path"}/>
Or
<JSP: Forward page = "path"}>
<JSP: Param name = "paramname" value = "paramvalue"/> ......
</Jsp: Forward>

Note:
1. Page = "path" is an expression or a string.
2. <JSP: param> name specifies the parameter name and value specifies the parameter value. The parameter is sent to a dynamic file. The parameter can be one or more values, but the file must be a dynamic file. To pass multiple parameters, you can use multiple <JSP: param> In a JSP file to send multiple parameters to a dynamic file.

Iii. usebean instructions

<JSP: usebean> A tag is used to create a bean instance on the JSP page and specify its name and scope.

Syntax:
<JSP: usebean id = "name" Scope = "Page | request | session | application" typespec/>
Typespec has the following possibilities:
Class = "classname" | class = "classname" type = "typename" | beanname = "beanname" type = "typename" | type = "typename" |

Note:
You must use class or type instead of both Class and beanname. Beanname indicates the bean name in the form of "A. B. C ".

Iv. getproperty command

<JSP: getproperty> the tag is used to obtain the bean property value, convert it into a string, and insert it into the output page.

Syntax:
<JSP: getproperty name = "name" property = "propertyname"/>

Note:
1. Before using <JSP: getproperty>, you must use <JSP: usebean> to create it.
2. You cannot use <JSP: getproperty> to retrieve an indexed property.
3. It can be used with the JavaBeans component <JSP: getproperty>, but cannot be used with Enterprise Java Bean.

5. setproperty command

<JSP: setproperty> tag indicates the attribute value in bean.

Syntax:
<JSP: setproperty name = "beanname" prop_expr/>
Among them, prop_expr has the following possible situations:
Property = "*" | property = "propertyname" | property = "propertyname" Param = "parametername" | property = "propertyname" value = "propertyvalue"

Note:
Use JSP: setproperty to assign values to the attributes of a bean. You can use either of the following methods.
1. Use JSP: setproperty: After JSP: usebean:
<JSP: usebean id = "myuser "... />
...
<JSP: setproperty name = "user" property = "user "... />
In this way, JSP: setproperty will be executed.
2. jsp: setproperty appears in the JSP: usebean Tag:
<JSP: usebean id = "myuser "... >
...
<JSP: setproperty name = "user" property = "user "... />
</Jsp: usebean>
In this way, JSP: setproperty is executed only when a new object is instantiated.

* The name value in <JSP: setproperty> should be the same as the id value in <JSP: usebean>.

Vi. plugin commands

<JSP: plugin> the tag indicates executing an applet or bean. If possible, you need to download a Java Plug-in to execute it.

Syntax:
<JSP: plugin
Type = "bean | applet"
Code = "classfilename"
Codebase = "classfiledirectoryname"
[Name = "instancename"]
[Archive = "uritoarchive,..."]
[Align = "bottom | top | Middle | left | right"]
[Height = "displaypixels"]
[Width = "displaypixels"]
[Hspace = "leftrightpixels"]
[Vspace = "topbottompixels"]
[Jreversion = "Maid number | 1.1"]
[Nspluginurl = "urltoplugin"]
[Iepluginurl = "urltoplugin"]>
[<JSP: Params>

Note:
<JSP: plugin> elements are used to play or display an object (typically an applet and bean) in a browser, and such display needs to be implemented in the browser's Java Plug-in.
When the JSP file is compiled and sent to the browser, the <JSP: plugin> element will be replaced with the <Object> or <embed> element based on the browser version. Note: <Object> is used for HTML 4.0 and <embed> is used for HTML 3.2.
In general, the <JSP: plugin> element specifies whether the object is an applet or bean, the class name, location, and where to download the Java Plug-in.

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