小峰servlet/jsp（7）jstl国际化标签库、sql标签库等
一、jstl国际化标签库：
fmt:setLocale 设定用户所在的区域；
fmt:formatDate 对日期进行格式化
fmt:requestEncoding 设置所有的请求编码;
fmt:bundle fmt:message 读取国际化资源；
fmt:formatNumber 格式化数字;
fmt:timeZone 设置临时时区
fmt:setLocale:
1 <body> 2 <% 3 pageContext.setAttribute("date",new Date()); 4 %> 5 中文日期： 6 <fmt:setLocale value="zh_CN"/> 7 <fmt:formatDate value="${date }"/> 8 <hr/> 9 英文日期： 10 <fmt:setLocale value="en_US"/> 11 <fmt:formatDate value="${date }"/> 12 </body>
fmt:requestEncoding:
1 <body> 2 <fmt:requestEncoding value="UTF-8"/> 3 </body>
fmt:bundle; fmt:message:
资源文件：
info_en_US.properties:
1 name=xiaofeng 2 info=Current user{0}:Welcome to use our system
info_zh_CN.properties:
1 name=\u5c0f\u950b 2 info=\u5f53\u524d\u7528\u6237{0}:\u6b22\u8fce\u4f7f\u7528\u672c\u7cfb\u7edf
1 <body> 2 <fmt:setLocale value="zh_CN"/> 3 <fmt:bundle basename="info"> 4 <fmt:message key="name" var="userName"/> 5 </fmt:bundle> 6 <h2>姓名：${userName }</h2> 7 <fmt:bundle basename="info"> 8 <fmt:message key="info" var="infomation"> 9 <fmt:param value="<font color='red'>小锋</font>"/> 10 </fmt:message> 11 </fmt:bundle> 12 <h2>信息：${infomation }</h2> 13 <hr/> 14 <fmt:setLocale value="en_US"/> 15 <fmt:bundle basename="info"> 16 <fmt:message key="name" var="userName"/> 17 </fmt:bundle> 18 <h2>姓名：${userName }</h2> 19 <fmt:bundle basename="info"> 20 <fmt:message key="info" var="infomation"> 21 <fmt:param value="<font color='red'>小锋</font>"/> 22 </fmt:message> 23 </fmt:bundle> 24 <h2>信息：${infomation }</h2> 25 </body>
//<fmt:param value="<font color='red'>小锋</font>"/>是为properties中的占位符动态塞数据;
fmt:formatNumber:
1 <body> 2 <!-- value:数值 ; type:数值类型; pattern:格式 --> 3 <fmt:formatNumber value="12" type="currency" pattern="＄.00"/> 4 <fmt:formatNumber value="12" type="currency" pattern="＄.0#"/> 5 <fmt:formatNumber value="1234567890" type="currency"/> 6 <fmt:formatNumber value="123456.7891" pattern="#,#00.0#"/> 7 </body>
fmt:formatDate:
1 <body> 2 <!-- value:数值 ; type:数值类型; pattern:格式 --> 3 <% 4 Date date=new Date(); 5 pageContext.setAttribute("date",date); 6 %> 7 <fmt:formatDate value="${date }" pattern="yyyy-MM-dd HH:mm:ss"/> 8 <hr/> 9 <fmt:formatDate value="${date }" pattern="yyyy-MM-dd"/> 10 </body>
fmt:timeZone:
1 <body> 2 <!-- value:数值 ; type:数值类型; pattern:格式 --> 3 <% 4 Date date=new Date(); 5 pageContext.setAttribute("date",date); 6 %> 7 当前时间：<fmt:formatDate value="${date }" pattern="yyyy-MM-dd HH:mm:ss"/> 8 <hr/> 9 格林尼治时间： 10 <fmt:timeZone value="GMT"> 11 <fmt:formatDate value="${date }" pattern="yyyy-MM-dd HH:mm:ss"/> 12 </fmt:timeZone> 13 </body>
二、jstl SQL标签库：
sql:setDataSource 设置JDBC连接；
sql:query 数据库查询操作
sql:update 数据库添加、修改、删除操作；
sql:transaction 数据库事务
sql:setDataSource/sql:query:
数据库中存在这样的表：t_student:
jsp页面要引入：<%@ taglib uri="http://java.sun.com/jsp/jstl/sql" prefix="sql" %>
1 <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> 2 <%@ taglib uri="http://java.sun.com/jsp/jstl/sql" prefix="sql" %> 3 <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%> 4 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 5 <html> 6 <head> 7 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 8 <title>Insert title here</title> 9 </head> 10 <body> 11 <h1>设置JDBC连接</h1> 12 <sql:setDataSource driver="com.mysql.jdbc.Driver" url="jdbc:mysql://localhost:3306/db_jstl" user="root" password="123456" /> 13 <sql:query var="result"> 14 select * from t_student; 15 </sql:query> 16 <h2>总记录数：${result.rowCount }</h2> 17 <table> 18 <tr> 19 <th>编号</th> 20 <th>学号</th> 21 <th>姓名</th> 22 <th>出生日期</th> 23 <th>性别</th> 24 </tr> 25 <c:forEach var="student" items="${result.rows }"> 26 <tr> 27 <td>${student.id }</td> 28 <td>${student.stuNo }</td> 29 <td>${student.stuName }</td> 30 <td>${student.birthday }</td> 31 <td>${student.sex }</td> 32 </tr> 33 </c:forEach> 34 </table> 35 </body> 36 </html>
访问展示：
sql:update:
增：
1 <body> 2 <h1>设置JDBC连接</h1> 3 <sql:setDataSource driver="com.mysql.jdbc.Driver" url="jdbc:mysql://localhost:3306/db_jstl" user="root" password="123456"/> 4 <h1>添加数据</h1> 5 <sql:update var="result" > 6 insert into t_student values(null,"008","草泥马","1991-1-1","男"); 7 </sql:update> 8 </body>
改：
1 <body> 2 <h1>设置JDBC连接</h1> 3 <sql:setDataSource driver="com.mysql.jdbc.Driver" url="jdbc:mysql://localhost:3306/db_jstl" user="root" password="123456"/> 4 <h1>修改数据</h1> 5 <sql:update var="result" > 6 update t_student set stuNo="010",sex="未知" where id=6 7 </sql:update> 8 </body>
删：
1 <body> 2 <h1>设置JDBC连接</h1> 3 <sql:setDataSource driver="com.mysql.jdbc.Driver" url="jdbc:mysql://localhost:3306/db_jstl" user="root" password="123456"/> 4 <h1>删除数据</h1> 5 <sql:update var="result" > 6 delete from t_student where id=6 7 </sql:update> 8 </body>
sql:transcation:
1 <body> 2 <h1>设置JDBC连接</h1> 3 <sql:setDataSource driver="com.mysql.jdbc.Driver" url="jdbc:mysql://localhost:3306/db_jstl" user="root" password="123456"/> 4 <h1>事务</h1> 5 <sql:transaction> 6 <sql:update var="result" > 7 insert into t_student values(null,"008","草泥马","1991-1-1","男"); 8 </sql:update> 9 </sql:transaction> 10 </body>
三、jstl xml标签库：
x:parse 解析xml;
x:out 输出xml文件的内容
x:set 把xml读取的内容保存到指定的属性范围
x:if 判断指定路径的内容是否符合判断的条件；
x:choose/x:when/x:otherwise 多条件判断
x:forEach 遍历
需要引入xalan.jar;
jsp文件需要引入：<%@ taglib uri="http://java.sun.com/jsp/jstl/xml" prefix="x"%>
有这样两个xml文件,usersInfo.xml; usersInfo2.xml:
usersInfo.xml:
1 <?xml version="1.0" encoding="UTF-8"?> 2 <users> 3 <user> 4 <name id="n1">张三</name> 5 <birthday>2011-1-1</birthday> 6 </user> 7 </users>
usersInfo2.xml:
1 <?xml version="1.0" encoding="UTF-8"?> 2 <users> 3 <user> 4 <name id="n1">张三</name> 5 <birthday>2011-1-1</birthday> 6 </user> 7 <user> 8 <name id="n2">王五</name> 9 <birthday>2011-1-2</birthday> 10 </user> 11 <user> 12 <name id="n3">赵六</name> 13 <birthday>2011-1-3</birthday> 14 </user> 15 </users>
文件存放路径：
1）x:parse x:out
1 <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> 2 <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%> 3 <%@ taglib uri="http://java.sun.com/jsp/jstl/xml" prefix="x"%> 4 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 5 <html> 6 <head> 7 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 8 <title>Insert title here</title> 9 </head> 10 <body> 11 <c:import var="usersInfo" url="usersInfo.xml" charEncoding="UTF-8"/> 12 <x:parse var="usersInfoXml" doc="${usersInfo }"/> 13 14 <h2>姓名：<x:out select="$usersInfoXml/users/user/name"/> 15 (ID:<x:out select="$usersInfoXml/users/user/name/@id"/>)</h2> 16 <h2>出生日期：<x:out select="$usersInfoXml/users/user/birthday"/></h2> 17 </body> 18 </html>
2) x:set
1 <body> 2 <c:import var="usersInfo" url="usersInfo.xml" charEncoding="UTF-8"/> 3 <x:parse var="usersInfoXml" doc="${usersInfo }"/> 4 5 <x:set var="userInfoXml" select="$usersInfoXml/users/user"/> 6 <h2>姓名：<x:out select="$userInfoXml/name"/></h2> 7 </body>
3) x:if
1 <body> 2 <c:import var="usersInfo" url="usersInfo.xml" charEncoding="UTF-8"/> 3 <x:parse var="usersInfoXml" doc="${usersInfo }"/> 4 <x:if select="$usersInfoXml/users/user/name/@id='n1'"> 5 <h2>有编号是n1的user信息</h2> 6 </x:if> 7 </body>
4) x:choose/x:when/x:otherwise
1 <body> 2 <c:import var="usersInfo" url="usersInfo.xml" charEncoding="UTF-8"/> 3 <x:parse var="usersInfoXml" doc="${usersInfo }"/> 4 <x:choose> 5 <x:when select="$usersInfoXml/users/user/name/@id='n2'"> 6 <h2>有编号是n2的user信息</h2> 7 </x:when> 8 <x:otherwise> 9 <h2>没有编号是n2的user信息</h2> 10 </x:otherwise> 11 </x:choose> 12 </body>
5) x:forEach:
1 <body> 2 <c:import var="usersInfo" url="usersInfo2.xml" charEncoding="UTF-8"/> 3 <x:parse var="usersInfoXml" doc="${usersInfo }"/> 4 <x:forEach select="$usersInfoXml/users/user" var="userInfoXml"> 5 <h2>姓名：<x:out select="$userInfoXml/name"/> 出生日期：<x:out select="$userInfoXml/birthday"/></h2> 6 <hr/> 7 </x:forEach> 8 </body>
四、jstl函数标签库：
jsp页面需要引入：
<%@ taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn"%>
1 <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> 2 <%@ taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn"%> 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 4 <html> 5 <head> 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 7 <title>Insert title here</title> 8 </head> 9 <body> 10 <% 11 pageContext.setAttribute("info","www.java1234.com"); 12 %> 13 <h2>查找java1234位置:${fn:indexOf(info,"java1234")}</h2> 14 <h2>判断java1234是否存在:${fn:contains(info,"java1234")}</h2> 15 <h2>截取:${fn:substring(info,0,5)}</h2> 16 <h2>拆分:${fn:split(info,".")[1]}</h2> 17 </body> 18 </html>
页面展示：
函数标签一些：
<c:if test="${fun:length(operation.rangeList) > 0}">
