Jsp custom tag instance

Last Update:2018-12-08 Source: Internet

Author: User

Tags dateformat

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In three steps:
1. Create a folder named tlds under the WEB-INF, and then create a tld file, such as formatTime. tld, the content is: Copy codeThe Code is as follows: <? Xml version = "1.0" encoding = "ISO-8859-1"?>
<! DOCTYPE taglib PUBLIC "-// Sun Microsystems, Inc. // dtd jsp Tag Library 1.1 // EN"
Http://java.sun.com/j2ee/dtds/web-jsptaglibrary_1_1.dtd>
<Taglib>
<Tlibversion> 1.0 </tlibversion>
<Jspversion> 1.1 </jspversion>
<Shortname> ntuc </shortname>
<Tag>
<Name> formatTimeAsString </name>
<Tagclass> com. ufinity. taglibTest. FormatTimeTag </tagclass>
<Bodycontent> empty </bodycontent>
<Attribute>
<Name> timestamp </name>
</Attribute>
<Attribute>
<Name> format </name>
</Attribute>
<Attribute>
<Name> showTH </name>
</Attribute>
<Attribute>
<Name> style </name>
</Attribute>
</Tag>
</Taglib>

2. Create a class with the following content:Copy codeThe Code is as follows: package com. ufinity. taglibTest;
Import java. io. IOException;
Import java. text. DateFormat;
Import java. text. ParseException;
Import java. text. SimpleDateFormat;
Import java. util. Calendar;
Import java. util. Date;
Import java. util. Locale;
Import javax. servlet. jsp. tagext. TagSupport;
/**
* Description of the class
*
* @ Author Wangqy
* @ Version 1.0
* @ Since 2009-8-25
*/
Public class FormatTimeTag extends TagSupport {
/**
* SerialVersionUID long
*/
Private static final long serialVersionUID = 8757501937718830491L;
Private String timestamp;
Private String format;
Private String showTH;
Private String style;
Public int doEndTag ()
{
Try
{
String info = this. convertDateTime (timestamp, format, Boolean. parseBoolean (showTH), style );
PageContext. getOut (). println (info );
}
Catch (IOException e ){
}
Return EVAL_PAGE;
}
Private String convertDateTime (String dateTime, String formater, boolean showTH, String caseStyle ){
String timePosted = null;
SimpleDateFormat dateFm = null;
DateFormat format = new SimpleDateFormat ("yyyyMMddHHmmss ");
Date formatTime = null;
Try {
FormatTime = format. parse (dateTime );
} Catch (ParseException e ){
Return null;
}
Calendar calendar = Calendar. getInstance ();
Calendar. setTime (formatTime );
If (showTH ){
Int day = calendar. get (Calendar. DAY_OF_MONTH );
String daySuffix = "th ";
If (day % 10) = 1 ){
DaySuffix = (day/10) = 1 )? "Th": "st ";
} Else if (day % 10) = 2 ){
DaySuffix = (day = 12 )? "Th": "nd ";
} Else if (day % 10) = 3 ){
DaySuffix = (day = 13 )? "Th": "rd ";
}
Formater = formater. substring (0, formater. indexOf ("") + "'"
+ DaySuffix + "'"
+ Formater. substring (formater. indexOf (""));
DateFm = new SimpleDateFormat (formater, Locale. ENGLISH );
} Else {
DateFm = new SimpleDateFormat (formater, Locale. ENGLISH );
}
TimePosted = dateFm. format (formatTime );
If (caseStyle. equals ("Upper ")){
TimePosted = timePosted. toUpperCase ();
} Else if (caseStyle. equals ("Lower ")){
TimePosted = timePosted. toLowerCase ();
}
Return timePosted;
}
Public void setFormat (String format ){
This. format = format;
}
Public void setShowTH (String showTH ){
This. showTH = showTH;
}
Public void setStyle (String style ){
This. style = style;
}
Public void setTimestamp (String timestamp ){
This. timestamp = timestamp;
}
}

3. Create a jsp page for test:Copy codeThe Code is as follows: <% @ page language = "java" pageEncoding = "UTF-8" %>
<% @ Taglib uri = "WEB-INF/tlds/formatTime. tld" prefix = "tf" %>
<Html>
<Head>
<Meta http-equiv = "Content-Type" content = "text/html; charset = gb2312"/>
<Title> custom tag example </title>
</Head>
<Body>

Convert "20090403132233"

Format: dd MMMM yyyy showTH: true style: after Upper is converted to: <tf: formatTimeAsString timestamp = "20090403132233" format = "dd MMMM yyyy" showTH = "true" style = "Upper"/> 
Format: dd MMMM yyyy showTH: true style: After Lower is converted to: <tf: formatTimeAsString timestamp = "20090403132233" format = "dd MMMM yyyy" showTH = "true" style = "Lower"/> 
Format: dd MMMM yyyy showTH: false style: after Upper is converted to: <tf: formatTimeAsString timestamp = "20090403132233" format = "dd MMMM yyyy" showTH = "false" style = "Upper"/> 
Format: dd MMMM yyyy showTH: true style: "" converted to: <tf: formatTimeAsString timestamp = "20090403132233" format = "dd MMMM yyyy" showTH = "true" style = ""/> 
</Body>
</Html>

OK. Here, timestamp is a given value. If it is dynamically obtained through the $ {} tag, you needCopy codeThe Code is as follows: <attribute>
<Name> timestamp </name>
</Attribute>

ChangeCopy codeThe Code is as follows: <attribute>
<Name> timestamp </name>
<Rtexprvalue> true </rtexprvalue>
</Attribute>

This article is an English version of an article which is originally in the Chinese language on aliyun.com and is provided for information purposes only. This website makes no representation or warranty of any kind, either expressed or implied, as to the accuracy, completeness ownership or reliability of the article or any translations thereof. If you have any concerns or complaints relating to the article, please send an email, providing a detailed description of the concern or complaint, to info-contact@alibabacloud.com. A staff member will contact you within 5 working days. Once verified, infringing content will be removed immediately.

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