Struts1入门实例(简单登录)
现在开始加入公司的核心项目,但由于项目开发比较早,所以使用的技术不是很新潮,前台用的还是struts1。
虽然不是什么新技术,但仍可以从中学到好多东西的。花了一个晚上的时间终于把struts1的流程跑通了。
省略了创建过程及加入jar包的过程,直接进入正题。
首页要在web.xml中添加相应的struts配置:
<servlet>
<servlet-name>action</servlet-name>
<servlet-class>
org.apache.struts.action.ActionServlet
</servlet-class>
<init-param>
<param-name>config</param-name>
<param-value>/WEB-INF/struts-config.xml</param-value>
</init-param>
<init-param>
<param-name>debug</param-name>
<param-value>2</param-value>
</init-param>
<init-param>
<param-name>detail</param-name>
<param-value>2</param-value>
</init-param>
<load-on-startup>2</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>action</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
然后在config所对应的目录下添加struts配置文件struts-config.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts-config PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 1.2//EN"
"http://jakarta.apache.org/struts/dtds/struts-config_1_2.dtd">
<struts-config>
<!-- ActionForm -->
<form-beans>
<!-- name:名称 type:类路径 -->
<form-bean name="loginForm" type="com.login.LoginForm">
</form-bean>
</form-beans>
<!-- 设置全局URL,必须写在Action前面,这样任何Action都可以使用 -->
<global-forwards>
<forward name="result" path="/result.jsp" />
</global-forwards>
<!-- 注册Action -->
<action-mappings>
<!-- name:名称 type:类路径 path:客户端(JSP)提交到服务器端时指定的路径(Form表单中的action=”/login.do" -->
<action path="/login" type="com.login.LoginAction"
name="loginForm" scope="request">
<!-- 局部URL,只有这个action可以使用 -->
<forward name="success" path="/success.jsp"></forward>
<forward name="error" path="/error.jsp"></forward>
</action>
</action-mappings>
</struts-config>
注:Action和Form的关系是一个Action只能对应一个Form(通过Action的name属性)
而一个Form可以被多个Action调用
LoginAction.java
package com.login;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
public class LoginAction extends Action {
@Override
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
LoginForm lf = (LoginForm) form;
String username = lf.getUsername();
String password = lf.getPassword();
String errorInfo = "";
String result = UserManager.getInstance().login(username, password);
if (result.equals("success")) {
request.setAttribute("username", username);
return mapping.findForward("success");
} else if (result.equals("username")) {
errorInfo = "密码错误";
} else {
errorInfo = "用户名错误";
}
request.setAttribute("errorInfo", errorInfo);
return mapping.findForward("error");
}
}
LoginForm.java
package com.login;
import javax.servlet.http.HttpServletRequest;
import org.apache.struts.action.ActionErrors;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionMapping;
public class LoginForm extends ActionForm {
private String username;
private String password;
public void reset(ActionMapping mapping, HttpServletRequest request) {
System.out.println("--------reset()-------------");
super.reset(mapping, request);
}
public ActionErrors validate(ActionMapping mapping,
HttpServletRequest request) {
System.out.println("--------validate()-------------");
return super.validate(mapping, request);
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
对我个人来说最重要的是前台jsp页面没有掌握,经常在页面上花费很多时间
在编写JSP页面时要用struts标签,而我经常会忘记
引入jsp标签
<%@ taglib uri="http://struts.apache.org/tags-html" prefix="html" %> <%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean" %>
index.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <%@ taglib uri="http://struts.apache.org/tags-html" prefix="html" %> <%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean" %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>首页</title> </head> <body> <html:form action="/login.do"> 用户名:<html:text property="username"></html:text><br/> 密码: <html:password property="password"></html:password><br/> <html:submit>submit</html:submit> </html:form> </body> </html>
展示结果(将Action的返回值展示到JSP页面上)
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <%@ taglib uri="http://struts.apache.org/tags-html" prefix="html"%> <%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>Error</title> </head> <body> <bean:write name="errorInfo" scope="request" /> </body> </html>