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jsp 自定义标签实例
来源: 互联网 发布时间:2014-10-17
本文导语: 分三步: 一、在WEB-INF 下建一个名为tlds的文件夹,再建一个tld文件,如 formatTime.tld,内容为: 代码如下: 1.0 1.1 ntuc formatTimeAsString com.ufinity.taglibTest.FormatTimeTag empty timestamp format showTH style 二、建一个class,内容为: ...
分三步:
一、在WEB-INF 下建一个名为tlds的文件夹,再建一个tld文件,如 formatTime.tld,内容为:
1.0
1.1
ntuc
formatTimeAsString
com.ufinity.taglibTest.FormatTimeTag
empty
timestamp
format
showTH
style
二、建一个class,内容为:
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;
}
}
三、建个jsp页面测试下:
自定义标签示例
format:dd MMMM yyyy showTH:true style:Upper 转换后为:
format:dd MMMM yyyy showTH:true style:Lower 转换后为:
format:dd MMMM yyyy showTH:false style:Upper 转换后为:
format:dd MMMM yyyy showTH:true style:"" 转换后为:
ok了。这里timestamp是一个给定值,如果是通过${}标签动态取的话,需要将tld文件的
timestamp
修改为
timestamp
true
一、在WEB-INF 下建一个名为tlds的文件夹,再建一个tld文件,如 formatTime.tld,内容为:
代码如下:
1.0
1.1
ntuc
formatTimeAsString
com.ufinity.taglibTest.FormatTimeTag
empty
timestamp
format
showTH
style
二、建一个class,内容为:
代码如下:
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;
}
}
三、建个jsp页面测试下:
代码如下:
自定义标签示例
转换“20090403132233”
format:dd MMMM yyyy showTH:true style:Upper 转换后为:
format:dd MMMM yyyy showTH:true style:Lower 转换后为:
format:dd MMMM yyyy showTH:false style:Upper 转换后为:
format:dd MMMM yyyy showTH:true style:"" 转换后为:
ok了。这里timestamp是一个给定值,如果是通过${}标签动态取的话,需要将tld文件的
代码如下:
timestamp
修改为
代码如下:
timestamp
true