struts1.X总结(10-20)

//结构
Group group = new Group();
group.setName("机电职业技术学院");

User user = new User();
user.setUsername("张三");
user.setAge(18);
user.setGroup(group);

request.setAttribute("user", user);

//map
Map mapValue = new HashMap();
mapValue.put("key1", "value1");
mapValue.put("key2", "value2");

request.setAttribute("mapvalue", mapValue);

//字符串数组
String[] strArray = new String[]{"a", "b", "c"};
request.setAttribute("strarray", strArray);

User[] users = new User[10];
for (int i=0; i<10; i++) {
User u = new User();
u.setUsername("U_" + i);
users[i] = u;
}
request.setAttribute("users", users);

List userList = new ArrayList();
for (int i=0; i<10; i++) {
User uu = new User();
uu.setUsername("UU_" + i);
userList.add(uu);
}
request.setAttribute("userlist", userList);

//empty
request.setAttribute("value1", null);
request.setAttribute("value2", "");
request.setAttribute("value3", new ArrayList());
request.setAttribute("value4", "123456");
return mapping.findForward("success");

客户端

<h1>测试EL表达式</h1><br>
<hr>
<li>普通字符串</li><br>
hello(jsp脚本):<%=request.getAttribute("hello") %><br>
hello(el表达式,el表达式的使用方法$和{}):${hello }<br>
hello(el表达式,el的隐含对象pageScope,requestScope,sessionScope,applicationScope,<br> 如果未指定scope,它的搜索顺序为pageScope~applicationScope):${requestScope.hello }<br>
hello(el表达式,scope=session):${sessionScope.hello }<br>
<p>
<li>结构,采用.进行导航，也称存取器</li><br>
姓名：${user.username }<br>
年龄：${user.age }<br>
所属组：${user.group.name }<br>
<p>
<li>输出map,采用.进行导航，也称存取器</li><br>
mapvalue.key1:${mapvalue.key1 }<br>
mapvalue.key2:${mapvalue.key2 }<br>
<p>
<li>输出数组,采用[]和下标</li><br>
strarray[2]:${strarray[1] }<br>
<p>
<li>输出对象数组,采用[]和下标</li><br>
userarray[3].username:${users[2].username }<br>
<p>
<li>输出list,采用[]和下标</li><br>
userlist[5].username:${userlist[4].username }<br>
<p>
<li>el表达式对运算符的支持</li><br>
1+2=${1+2 }<br>
10/5=${10/5 }<br>
10 div 5=${10 div 5 }<br>
10%3=${10 % 3 }<br>
10 mod 3=${10 mod 3 }<br>
<!--
==/eq
!=/ne
</lt
>/gt
<=/le
>=/ge
&&/and
||/or
!/not
//div
%/mod
-->
<li>测试empty</li><br>
value1:${empty value1 }<br>
value2:${empty value2 }<br>
value3:${empty value3 }<br>
value4:${empty value4 }<br>
value4:${!empty value4 }<br>

JSTL核心库标签

Jstl.jar是接口
Standard.jar是实现

页面加入<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>

普通属性和文本的使用

服务器
//普通属性
request.setAttribute("hello", "Hello World");
//html文本
request.setAttribute("bj", "<font color='red'>北京欢迎您</font>");

客户端
<h1>测试jstl核心库</h1>
<hr>
<li>测试c:out</li><br>
hello(default):<c:out value="${hello}"/><br>
hello(el表达式):${hello }<br>
hello(default="123"):<c:out value="${abc}" default="123"/><br>
//等同于
hello(default="123"):<c:out value="${abc}">123</c:out><br>
bj(defalut):<c:out value="${bj}"/><br>
bj(escapeXml="true"):<c:out value="${bj}" escapeXml="true"/><br>
bj(escapeXml="false"):<c:out value="${bj}" escapeXml="false"/><br>
//等同于
bj(el表达式):${bj }<br>
<p>
<li>测试c:set和c:remove</li><br>
<c:set value="123" var="temp"/>//默认是在page页面有效
temp:${temp }<br>
<c:remove var="temp"/>
temp:${temp }<br>
<p>

条件分支

服务器
//测试条件控制标签
request.setAttribute("v1", 1);
request.setAttribute("v2", 2);
request.setAttribute("v3", new ArrayList());
request.setAttribute("v4", "test");
客户端
<li>测试条件控制标签c:if</li><br>
<c:if test="${v1 lt v2}" var="v">
v1小于v2<br>v=${v }<br>
</c:if>
<c:if test="${empty v3}">
v3为空<br>
</c:if>
<c:if test="${empty v4}">
v4为空<br>
</c:if>
<p>
<li>测试条件控制标签c:choose,c:when,c:otherwise</li><br>
<c:choose>
<c:when test="${v1 lt v2}">
v1小于v2<br>
</c:when>
<c:otherwise>
v1大于v2<br>
</c:otherwise>
</c:choose>
<c:choose>
<c:when test="${empty v4}">
v4为空<br>
</c:when>
<c:otherwise>
v4不为空<br>
</c:otherwise>
</c:choose>
<p>
循环控制标签

服务器

//测试c:forEach
Group group = new Group();
group.setName("机电职业技术学院");

List userList = new ArrayList();
for (int i=0; i<10; i++) {
User user = new User();
user.setUsername("user_" + i);
user.setAge(18+i);
user.setGroup(group);
userList.add(user);
}

request.setAttribute("userlist", userList);

//测试循环输出map
Map map = new HashMap();
map.put("k1", "v1");
map.put("k2", "v2");
request.setAttribute("mapvalue", map);

客户端

<li>测试循环控制标签c:forEach</li><br>
<table border="1">
<tr>
<td>姓名</td>
<td>年龄</td>
<td>所属组</td>
</tr>
<c:choose>
<c:when test="${empty userlist}">
<tr>
<td colspan="3">没有符合条件的数据!</td>
</tr>
</c:when>
<c:otherwise>
<c:forEach items="${userlist}" var="u">
<tr>
<td>${u.username }</td>
<td>${u.age }</td>
<td>${u.group.name }</td>
</tr>
</c:forEach>
</c:otherwise>
</c:choose>
</table>
<p>
<li>测试循环控制标签c:forEach,varstatus</li><br>
<table border="1">
<tr>
<td>姓名</td>
<td>年龄</td>
<td>所属组</td>
</tr>
<c:choose>
<c:when test="${empty userlist}">
<tr>
<td colspan="3">没有符合条件的数据!</td>
</tr>
</c:when>
<c:otherwise>
<c:forEach items="${userlist}" var="user" varStatus="vs">
<c:choose>
<c:when test="${vs.count % 2 == 0}">
<tr bgcolor="red">
</c:when>
<c:otherwise>
<tr>
</c:otherwise>
</c:choose>
<td>
<c:out value="${user.username}"/>
</td>
<td>
<c:out value="${user.age}"/>
</td>
<td>
<c:out value="${user.group.name}"/>
</td>
</tr>
</c:forEach>
</c:otherwise>
</c:choose>
</table>
<p>
<li>测试循环控制标签c:forEach,begin,end,step</li><br>
<table border="1">
<tr>
<td>姓名</td>
<td>年龄</td>
<td>所属组</td>
</tr>
<c:choose>
<c:when test="${empty userlist}">
<tr>
<td colspan="3">没有符合条件的数据!</td>
</tr>
</c:when>
<c:otherwise>
<c:forEach items="${userlist}" var="user" begin="2" end="8" step="2">
<tr>
<td>${user.username}</td>
<td>${user.age}</td>
<td>${user.group.name }</td>
</tr>
</c:forEach>
</c:otherwise>
</c:choose>
</table>
<p>
<li>测试循环控制标签c:forEach，普通循环</li><br>
<c:forEach begin="1" end="10">
a<br>
</c:forEach>
<p>
<li>测试循环控制标签c:forEach，输出map</li><br>
<c:forEach items="${mapvalue}" var="v">
${v.key }=${v.value }<br>
</c:forEach>
<p>

forTokens标签逗号表达式

服务器

//测试c:forTokens
request.setAttribute("strTokens", "1,2,3,4,5,6");

客户端

<li>测试循环控制标签c:forTokens</li><br>
<c:forTokens items="${strTokens}" delims="," var="v">
${v }<br>
</c:forTokens>
<p>
<li>测试c:catch</li><br>
<%
try {
Integer.parseInt("asdfsdf");
}catch(Exception e) {
out.println(e.getMessage());
}
%>
<p>
<c:catch var="exinfo">
<%
Integer.parseInt("asdfsdf");
%>
</c:catch>
${exinfo }<br>
<p>
<li>测试c:import</li><br>//相当于include
<c:import url="http://localhost:8080/struts_login"/>
<p>
<li>测试c:url和c:param</li><br>
<c:url value="http://localhost:8080/drp/sysmgr/user_add.jsp" var="v">
<c:param name="username" value="Jack"/>
<c:param name="age" value="20"/>
</c:url>
${v }<br>
<li>测试:redirect</li><br>
//代替上面的url属于相对路径
<c:redirect context="/struts_login" url="/index.jsp"/>

格式化标签库

格式化日期

服务器端
request.setAttribute("today", new Date());

客户端

<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt"%>
<h1>测试jstl格式化库</h1>
<hr>
<li>测试日期的格式化</li><br>
today(default):<fmt:formatDate value="${today}"/><br>
today(type="date"):<fmt:formatDate value="${today}" type="date"/><br>
today(type="time"):<fmt:formatDate value="${today}" type="time"/><br>
today(type="both"):<fmt:formatDate value="${today}" type="both"/><br>
today(dateStyle="short"):<fmt:formatDate value="${today}" dateStyle="short"/><br>
today(dateStyle="medium"):<fmt:formatDate value="${today}" dateStyle="medium"/><br>
today(dateStyle="long"):<fmt:formatDate value="${today}" dateStyle="long"/><br>
today(dateStyle="full"):<fmt:formatDate value="${today}" dateStyle="full"/><br>
today(pattern="yyyy/MM/dd HH:mm:ss"):<fmt:formatDate value="${today}" pattern="yyyy/MM/dd HH:mm:ss"/><br>
today(pattern="yyyy/MM/dd HH:mm:ss"):<fmt:formatDate value="${today}" pattern="yyyy/MM/dd HH:mm:ss" var="d"/><br>
${d }<br>
<p>

格式化数字

服务器

request.setAttribute("n", 123456.123);

request.setAttribute("p", 0.12345);

客户端

<p>
<li>测试数字的格式化</li><br>
n(default):<fmt:formatNumber value="${n}"/><br>
n(pattern="###,###.##"):<fmt:formatNumber value="${n}" pattern="###,###.##"/><br>
n(pattern="###,###.0000"):<fmt:formatNumber value="${n}" pattern="###,###.0000"/><br>
n(groupingUsed="false"):<fmt:formatNumber value="${n}" groupingUsed="false"/><br>
n(minIntegerDigits="10"):<fmt:formatNumber value="${n}" minIntegerDigits="10"/><br>
n(type="currency"):<fmt:formatNumber value="${n}" type="currency"/><br>
n(type="currency"):<fmt:formatNumber value="${n}" type="currency" currencySymbol="$"/><br>
n(type="percent"):<fmt:formatNumber value="${p}" type="percent" maxFractionDigits="2" minFractionDigits="2"/><br>

函数库的使用

服务器端

request.setAttribute("hello", "hello world");

List list = new ArrayList();
list.add("t1");
list.add("t2");

request.setAttribute("list", list);

客户端//参看jstl-1—1-mr2-spec.pdf
<%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions"%>
<h1>测试jstl函数库</h1>
<hr>
hello.length=(jsp脚本):<%=((String)request.getAttribute("hello")).length() %><br>
hello.length(jstl函数库，函数调用必须在el表达式中 前缀+冒号+函数名):${fn:length(hello) }<br>
list.length:${fn:length(list) }<br>
<p>

自定义函数库