El expression-UDF)

you can see an interesting application, Turn it off, huh, huh !!

1. definition class myfunction ( note: method must be Public static)

Package Com. tgb. jstl;


/**  
 
* UDF implementation class in the jstl label

*
 
  */

Public Class Myfunctions {

Public Static String sayhello (string name ){

Return "Hello" + name;

}

}

2.ProvideTLDDescription file,This file can be placed inWEB-INFOr under its Directory.

<? XML version = "1.0" encoding = "UTF-8" ?>

< Taglib Xmlns = "Http://java.sun.com/xml/ns/j2ee"
Xmlns: xsi = "Http://www.w3.org/2001/XMLSchema-instance"
Xsi: schemalocation = "Http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
Version = "2.0" >
< Description > Myfunctions Library </ Description >
< Display-name > Jstl Functions </ Display-name >
< Tlib-version > 1.1 </ Tlib-version >

<! -- The so-called "abbreviation" here can be written at will -->
< Short-name > MFN </ Short-name >
<! -- The URI here can be written at will -->
< Uri > Http://www.tgb.com/functions </ Uri >

< Function >
<! -- The name can be written as needed. -->
< Name > Say </ Name >
<! -- It is most important to specify the class location and some important information about the class method. -->
< Function-class > Com. tgb. jstl. myfunctions </ Function-class >
< Function-Signature > Java. Lang. String sayhello (Java. Lang. String) </ Function-Signature >
</ Function >

</ Taglib >

3.InJSPUseTaglibIntroduce function library

< % @ Taglib Uri = Http://www.tgb.com/functions"   Prefix = "MFN" % >  

4. in El + colon + use function names

call functions related to the function library, El Expression.

$ {MFN: say ("Tom")} <--- "Tom" can be changed to an El expression