struts1.X总结(1-10)_struts1.x　setattribute getparametervalues-优快云博客

本文链接：https://blog.youkuaiyun.com/pingfanwuzhe/article/details/5583621

struts总结

2009-2-13 向先函制作

2009-2-19结束

1、路径问题

b.jsp

<p>

</body>

2、转发问题

* String username=req.getParameter("username");

* UserManager user=new UserManager();

* List list=user.addAllUser(username);

* req.setAttribute("username", list);

/* req.getRequestDispatcher("/a/b/b.jsp").forward(req, res);

3、配置filter应该注意的问题

配置成*.jsp

4、servlet匹配模式

*.do

/servlet/*

/servlet/TestServlet

5、原始的MVC的做法

接口类

public interface Action {

public String service(HttpServletRequest req, HttpServletResponse res);

}

实现类

public class AddUser implements Action {

public String service(HttpServletRequest req, HttpServletResponse res) {

// TODO Auto-generated method stub

System.out.println("-------addUser---------");

String username=req.getParameter("username");

UserManager user=new UserManager();

List list=user.addAllUser(username);

req.setAttribute("username", list);

return "/a/b/b.jsp";

}

调用action类

public class TestServlet extends HttpServlet {

@Override

protected void service(HttpServletRequest req, HttpServletResponse res)

throws ServletException, IOException {

String reqURI = req.getRequestURI();

System.out.println(reqURI);

String path = reqURI.substring(reqURI.indexOf("/", 1));

path = path.substring(0, path.indexOf("."));

System.out.println(path);

String forword = "";

if ("/servlet/addUser".equals(path)) {

Action action=new AddUser();

forword=action.service(req, res);

} else if ("/servlet/modifyUser".equals(path)) {

System.out.println("-------modifyUser---------");

} else if ("/servlet/delUser".equals(path)) {

System.out.println("-------delUser---------");

}

req.getRequestDispatcher(forword).forward(req, res);

}

更进配置的方法

6、实现struts mvc原理

6、服务器验证失效

<action

validate="FALSE"

7、单例的方法

设置：

public class UserManager {

private static UserManager instance = new UserManager();

private UserManager() {}

public static UserManager getInstance() {

return instance;

}

获取：

UserManager.getInstance().login(username, password);

8、异常处理的整个流程

建立两个异常类

public class PasswordErrorException extends RuntimeException {

}

public class UserNotFoundException extends RuntimeException {

}

业务调用类

public class UserManager {

private static UserManager instance = new UserManager();

private UserManager() {}

public static UserManager getInstance() {

return instance;

}

public void login(String username, String password) {

if (!"admin".equals(username)) {

throw new UserNotFoundException();

}

if (!"admin".equals(password)) {

throw new PasswordErrorException();

}

Action转发

String errorInfo = "";

try {

UserManager.getInstance().login(username, password);

//request.setAttribute("username", username);

return mapping.findForward("success");

}catch(UserNotFoundException unfe) {

unfe.printStackTrace();

errorInfo = "用户不能找到，用户名称=[" + username + "]";

}catch(PasswordErrorException pee) {

pee.printStackTrace();

errorInfo = "密码错误";

}

request.setAttribute("errorinfo", errorInfo);

return mapping.findForward("error");

}

页面调用

失败页面

</head>

<body>

<%=request.getAttribute("errorinfo") %>

成功页面

<%@ page import="com.bjsxt.struts.*" %>

</head>

<body>

LoginActionForm laf = (LoginActionForm)request.getAttribute("loginForm");//因为作用域是request

<%=laf.getUsername() %>,登录成功

9、小问题

<action-mappings>

<action path="/login"

type="com.bjsxt.struts.LoginAction"

name="loginForm"

scope="request"

validate="false"

attribute="login"

去数据的时候先会取attribute的数据，参考源码中的 prosser

10、struts的标签库不怎么使用了！是视图技术运行在服务器端的

struts标签的配置和使用

配置：

* 在struts-config.xml文件中加入

<message-resources parameter="MessageResources" />

* 拷贝MessageResources.properties文件到src下

使用：查考struts-1.2.9-bin/webapps/struts-documentation/userGuide/index

l 采用taglib指令引入在struts.jar当中的META-INF中有

服务器端

测试beanwriter

//普通属性

request.setAttribute("hello", "Hello World");

//html文本

request.setAttribute("bj", "<font color='red'>北京欢迎您</font>");

//日期

request.setAttribute("today", new Date());

//数字

request.setAttribute("n", 123456.987);

//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);

return mapping.findForward("success");

客户端：

<%@ taglib prefix="bean" uri="http://struts.apache.org/tags-bean"%>

<h1>测试BeanWrite</h1>

<hr>

<li>普通字符串</li><br>

hello(jsp脚本):<%=request.getAttribute("hello") %><br>

hello(标签):<bean:write name="hello"/><br>

<p>

<li>html文本</li><br>

bj(default):<bean:write name="bj"/><br>

bj(filter="true"):<bean:write name="bj" filter="true"/><br>

bj(filter="false"):<bean:write name="bj" filter="false"/><br>

<p>

<li>格式化日期</li><br>

today(default):<bean:write name="today"/><br>

today(format="yyyy-MM-dd HH:mm:ss"):<bean:write name="today" format="yyyy-MM-dd HH:mm:ss"/>

<p>

<li>格式化数字</li><br>

n(default):<bean:write name="n"/><br>

n(format="###,###.####"):<bean:write name="n" format="###,###.####"/><br>

n(format="###,###.####"):<bean:write name="n" format="###,###.0000"/><br>

<p>

<li>结构</li><br>//标签的执行是在服务器端执行的，不是在客户端执行的，使用双引号没问题

姓名：<input type="text" value="<bean:write name="user" property="username"/>"><br>

年龄：<input type="text" value="<bean:write name="user" property="age"/>"><br>

所属组：<input type="text" value="<bean:write name="user" property="group.name"/>"><br>

</body>

测试logic 对象为null就不存在了“”就存在

服务器端

request.setAttribute("attr1", null);

客户端

<%@taglibprefix="logic"uri="http://struts.apache.org/tags-logic">

<h1>测试empty,notEmpty,present,notPresent</h1>

<hr>

<logic:empty name="attr1">

attr1为空<br>

</logic:empty>

<logic:notEmpty name="attr1">

attr1不为空<br>

</logic:notEmpty>

<logic:present name="attr1">

attr1存在<br>

</logic:present>

<logic:notPresent name="attr1">

attr1不存在<br>

</logic:notPresent>

测试Iterate

服务器端

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);

客户端

<%@ taglib prefix="bean" uri="http://struts.apache.org/tags-bean"%>

<%@ taglib prefix="logic" uri="http://struts.apache.org/tags-logic"%>

<h1>测试Iterate</h1>

<hr>

<li>jsp脚本</li><br>

<tr>

</tr>

List userList = (List)request.getAttribute("userlist");

if (userList == null || userList.size() == 0) {

<tr>

<td colspan="3">没有符合条件的数据!</td>

</tr>

}else {

for (Iterator iter=userList.iterator(); iter.hasNext(); ) {

User user = (User)iter.next();

<tr>

</tr>

}

</table>

<p>

<tr>

</tr>

<logic:empty name="userlist">

<tr>

<td colspan="3">没有符合条件的数据!</td>

</tr>

</logic:empty>

<logic:notEmpty name="userlist">

<logic:iterate id="u" name="userlist">

<tr>

<td>

<bean:write name="u" property="username"/>

</td>

<td>

<bean:write name="u" property="age"/>

</td>

<td>

<bean:write name="u" property="group.name"/>

</td>

</tr>

</logic:iterate>

</logic:notEmpty>

</table>

11、（表达式语言）el和（标准标签库）Jstl

注意：jstl必须在能够支持j2ee1.4/servlet2.4/jsp2.0版本上的容器才能运行，这个环境是目前较为常用的环境

是不是servlet2.4以上版本看web.xml中的

xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee

http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">

el表达式的使用

服务器

//普通字符串

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