?????? 小弟不才，最近做了一个关于日期显示的JSP自定义标签，具体功能：可以自定义显示起始和结束时间，也可以传入初始化参数，文件一加载便可一显示。
????? 具体说明文档如下：
SelectDateTag使用说明：
功能：该自定义标签为填充日期的下拉列表，包括三个下拉列表，分别为年月日，可以自定义设置下拉列表的起始和结束时间。
使用方法：复制com.sjdd.tag包下的BaseTag.class和SelectDateTag.class,将WEB-INF/taglib下的
SelectDateTag.tld以相同目录存放到需要配置的项目中。
在需要添加该自定义标签的JSP文件中加入如下代码：
“
<%@ taglib uri="/tagslib/SelectDate" prefix="SelectDate" %>
<SelectDate:SelectDate name="begin" begin="20000101" end="20201231" init="20101231"/>
”
参数说明："name"为使用的部分下拉列表的名称及id(选填)，具体形如"begin_year","begin_month","begin_day", 默认为"_year","_month","_day"；
"begin"为下拉列表开始时间(选填)，如果没有配置"init"也为默认时间，默认为"19900101"；
"end"为下拉列表结束时间(选填)，默认为"20201231"；
"init"为初始化时间(选填)，默认为当前日期。
范例见：WebRoot/testSelectDate.jsp
另：如果需要添加多个组件，则需要设置不同的name属性。
?
这是用于输出的父标签：
package com.sjdd.tag;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.TagSupport;
/**
*
* @Description:基本标签
* @author:bao
* @date:Dec 19, 2010
*/
public class BaseTag extends TagSupport {
private static final long serialVersionUID = 1L;
public int outPrint(StringBuffer content) throws JspException {
if(content==null){
return EVAL_PAGE;
}
try {
this.pageContext.getOut().write(content.toString());
} catch (Exception e) {
e.printStackTrace();
throw new JspException();
}
return EVAL_PAGE;
}
}
?
这是处理的主体标签类：
package com.sjdd.tag;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.jsp.JspException;
import com.sjdd.tag.datebean.DateHandler;
import com.sjdd.tag.datebean.Option;
public class SelectDateTag extends BaseTag {
private static final long serialVersionUID = 1L;
// 下拉列表的名称，形如"begin_year","_year"
private String name;
// 开始日期
private int begin = 19900101;
// 结束日期
private int end = 20201231;
// 初始化日期,默认值为当前日期
private int init;
public String getName() {
if(this.name==null){
name="";
}
return name;
}
public void setName(String name) {
this.name = name;
}
public int getBegin() {
return begin;
}
public void setBegin(int begin) {
int initBegin = DateHandler.varifyAsInit(begin, 19900101);
this.begin = initBegin;
}
public int getEnd() {
return end;
}
public void setEnd(int end) {
int initEnd = DateHandler.varifyAsInit(end, 20201231);
this.end = initEnd;
}
public int getInit() {
if(init==0){
init = DateHandler.getCurrentShortDate();
}
return init;
}
public void setInit(int init) {
int initial = DateHandler.varifyAsInit(init, DateHandler.getCurrentShortDate());
this.init = initial;
}
/**
* @Description:创建年下拉列表
* @return List<Option>
*/
public List<Option> buildYearOptions() {
List<Integer> yearList = new ArrayList<Integer>();
int beginYear = DateHandler.getYear(begin);
int endYear = DateHandler.getYear(end);
for (int i = beginYear; i <= endYear; i++) {
yearList.add(i);
}
return Option.buildOptions(yearList);
}
public List<Option> buildMonthOptions() {
List<Integer> monthList = new ArrayList<Integer>();
for (int i = 1; i <= 12; i++) {
monthList.add(i);
}
return Option.buildOptions(monthList);
}
public List<Option> buildDayOptions(int year, int month) {
List<Integer> yearList = new ArrayList<Integer>();
int maxDay = DateHandler.getMaxDayValue(year, month);
for (int i = 1; i <= maxDay; i++) {
yearList.add(i);
}
return Option.buildOptions(yearList);
}
@Override
public int doEndTag() throws JspException {
int yearValue = 2010;
int monthValue = 1;
StringBuffer content = new StringBuffer();
content.append("<select name=\"").append(getName()).append("_year\" id=\"").append(name).append(
"_year\" class=\"select\" onchange='"+getName()+"changeDay();'>\n");
for (Option year : buildYearOptions()) {
content.append(" <option value=\"").append(year.getValue()).append("\"");
if (DateHandler.getYear(getInit()) == year.getValue()) {
content.append(" selected=\"selected\"");
yearValue = year.getValue();
}
content.append(">").append(year.getLabel()).append("</option>\n");
}
content.append("</select>\n");
content.append("<select name=\"").append(getName()).append("_month\" id=\"").append(name)
.append("_month\" class=\"select\" onchange='"+getName()+"changeDay();'>\n");
for (Option month : buildMonthOptions()) {
content.append(" <option value=\"").append(month.getValue()).append("\"");
if (DateHandler.getMonth(getInit()) == month.getValue()) {
content.append(" selected=\"selected\"");
monthValue = month.getValue();
}
content.append(">").append(month.getLabel()).append("</option>\n");
}
content.append("</select>\n");
content.append("<select name=\"").append(getName()).append("_day\" id=\"").append(name).append(
"_day\" class=\"select\">\n");
for (Option day : buildDayOptions(yearValue, monthValue)) {
content.append(" <option value=\"").append(day.getValue()).append("\"");
if (DateHandler.getDay(getInit()) == day.getValue()) {
content.append(" selected=\"selected\"");
}
content.append(">").append(day.getLabel()).append("</option>\n");
}
content.append("</select>\n");
content.append("<script type=\"text/javascript\">\n");
content.append(" function "+getName()+"changeDay() {\n");
content.append(" var year = document.getElementById(\"" + getName() + "_year\").value;\n");
content.append(" var month = document.getElementById(\"" + getName() + "_month\").value;\n");
content.append(" var dayObj = document.getElementById(\"" + getName() + "_day\");\n");
content.append(" fillDayOptions(dayObj,getMaxDayInMonth(year,month));\n");
content.append(" }\n");
content.append(" function getMaxDayInMonth(year, month) {\n");
content.append(" var month = parseInt(month, 10) + 1;\n");
content.append(" var d = new Date(year + '/' + month + '/' + 0);\n");
content.append(" return d.getDate();\n");
content.append(" }\n");
content.append(" function fillDayOptions(obj, maxDay) {\n");
content.append(" obj.innerHTML = '';\n");
content.append(" for (i = 1; i <= maxDay; i++) {\n");
content.append(" var varItem = new Option(i, i);\n");
content.append(" obj.options.add(varItem);\n");
content.append(" }\n");
content.append(" }\n");
content.append("</script>\n");
return this.outPrint(content);
}
}
?
还包括两个实体bean：
package com.sjdd.tag.datebean;
import java.util.Calendar;
/**
* @Description:日期处理类
* @author:bao
* @date:Jan 1, 2011
*/
public class DateHandler {
private int year;
private int month;
private int day;
public int getYear() {
return year;
}
public void setYear(int year) {
this.year = year;
}
public int getMonth() {
return month;
}
public void setMonth(int month) {
this.month = month;
}
public int getDay() {
return day;
}
public void setDay(int day) {
this.day = day;
}
public DateHandler() {
super();
}
/**
* @Description:获取参数月中最大的天数值
* @param year
* @param month
* @return int
*/
public static int getMaxDayValue(int year, int month) {
Calendar time = Calendar.getInstance();
time.clear();
time.set(Calendar.YEAR, year); // year 为 int
time.set(Calendar.MONTH, month - 1);// 注意,Calendar对象默认一月为0
int max = time.getActualMaximum(Calendar.DAY_OF_MONTH);// 本月份的天数
return max;
}
/**
* @Description:获取当前日期，并转换为形如"20101231"格式的整型
* @return int
*/
public static int getCurrentShortDate() {
Calendar cal = Calendar.getInstance();
int date = cal.get(Calendar.YEAR) * 10000 + (cal.get(Calendar.MONTH) + 1) * 100
+ cal.get(Calendar.DAY_OF_MONTH);
return date;
}
/**
* @Description:验证date是否符合形如"20100101"格式，返回最符合要求的日期格式
* @param date
* @return int
*/
public static int varifyAsInit(int date, int defaultValue) {
String dateStr = Integer.toString(date);
// 如果输入数字不是8位，则使用默认的数字
if (dateStr.length() != 8) {
return defaultValue;
}
//返回最接近的日期
return getYear(date) * 10000 + getMonth(date) * 100 + getDay(date);
}
/**
* @Description:获取合法的日数
* @param date
* @return int
*/
public static int getDay(int date) {
int day = date % 100;
int maxDay = getMaxDayValue(getYear(date), getMonth(date));
if (day > maxDay) {
day = maxDay;
}
return day;
}
/**
* @Description:获取合法的月数
* @param date
* @return int
*/
public static int getMonth(int date) {
int month = date / 100 % 100;
if (month > 12) {
month = 12;
} else if (month < 1) {
month = 1;
}
return month;
}
/**
* @Description:获取合法的年数
* @param date
* @return int
*/
public static int getYear(int date) {
return date / 10000;
}
}
?
package com.sjdd.tag.datebean;
import java.util.ArrayList;
import java.util.List;
/**
* @Description:保存下拉列表中每一项的value值和显示内容
* @author:bao
* @date:Jan 1, 2011
*/
public class Option {
private String label;
private int value;
public String getLabel() {
return label;
}
public void setLabel(String label) {
this.label = label;
}
public int getValue() {
return value;
}
public void setValue(int value) {
this.value = value;
}
public Option(String label, int value) {
super();
this.label = label;
this.value = value;
}
public static List<Option> buildOptions(List<Integer> options){
List<Option> buildList = new ArrayList<Option>();
for(int option:options){
buildList.add(new Option(Integer.toString(option),option));
}
return buildList;
}
}
?
下面是tld文件：
<?xml version="1.0" encoding="UTF-8"?> <taglib version="2.0" 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"> <tlib-version>1.0</tlib-version> <short-name>SelectDate</short-name> <uri>/tagslib/SelectDate</uri> <tag> <name>SelectDate</name> <tag-class>com.sjdd.tag.SelectDateTag</tag-class> <body-content>empty</body-content> <attribute> <name>name</name> <required>false</required> </attribute> <attribute> <name>begin</name> <required>false</required> </attribute> <attribute> <name>end</name> <required>false</required> </attribute> <attribute> <name>init</name> <required>false</required> </attribute> </tag> </taglib>
?
这个是测试文件：
<%@ page language="java" pageEncoding="UTF-8"%>
<%@ taglib uri="/tagslib/SelectDate" prefix="SelectDate" %>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'testSelectDate.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
This is my JSP page. <br>
开始时间：<SelectDate:SelectDate name="begin" begin="20001010" end="21251231" init="20100102"/><br>
开始时间：<SelectDate:SelectDate/><br>
</body>
</html>
?
最下面为该功能的压缩包，如果各位同仁发现哪里有问题，请留言，期待与你共同进步。?