Struts2之Crud综合实例

本文是Struts2的综合实例，主要包含以下功能

添加，删除，修改，查询用户
上传，下载图片
拦截器实现登陆功能
验证器检查输入

下载图片功能以前没有实现过，步骤如下

在类中增加两个属性

//文件下载private InputStream inputStream;private String imageFileName;

下载方法实现

public String download(){path = ServletActionContext.getRequest().getParameter("path");filename = ServletActionContext.getRequest().getParameter("filename");String storePath = ServletActionContext.getServletContext().getRealPath("/files");try {inputStream = new FileInputStream(storePath+"\\"+path+"\\"+filename);} catch (FileNotFoundException e) {e.printStackTrace();}return SUCCESS;}

配置struts.xml

<action name="download" class="cn.itcast.domain.User" method="download"><interceptor-ref name="mydefaultstack"></interceptor-ref><result type="stream" name="success"><param name="contentType">application/octet-stream</param><param name="inputStream">inputStream</param><!-- 输入是对应的动作类中的那个字段 --><param name="contentDisposition">attachment;filename=${filename}</param><!-- 要下载的文件名 --></result><result name="login">/login.jsp</result></action>

JSP页面实现

<c:url value="/user/download" var="url"><c:param name="path" value="${user.path}"></c:param><c:param name="filename" value="${user.filename}"></c:param></c:url><a href="${url}">下载</a>

登陆验证功能

定义拦截器类

package cn.itcast.interceptor;import javax.servlet.http.HttpSession;import org.apache.struts2.ServletActionContext;import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.Interceptor;public class PermissionInterceptor implements Interceptor {public void destroy() {}public void init() {}public String intercept(ActionInvocation invocation) throws Exception {HttpSession session = ServletActionContext.getRequest().getSession();Object obj = session.getAttribute("user");if(obj==null){return "login";}else{return invocation.invoke();}}}

struts.xml中的配置

<package name="mydefault" extends="struts-default"><interceptors><interceptor name="permissionInterceptor" class="cn.itcast.interceptor.PermissionInterceptor"></interceptor><interceptor-stack name="mydefaultstack"><interceptor-ref name="defaultStack"></interceptor-ref><interceptor-ref name="permissionInterceptor"></interceptor-ref></interceptor-stack></interceptors></package>

在其他Action中使用拦截

<interceptor-ref name="mydefaultstack"></interceptor-ref>

条件查询实现

JSP页面

<td><s:form action="user_queryCondition" namespace="/user"><s:textfield name="username" label="用户名"></s:textfield><s:select list="#{'0':'女','1':'男'}" label="性别" name="sex" headerKey="" headerValue="请选择"></s:select><s:select label="学历" name="education" list="#{'研究生':'研究生','本科':'本科','专科':'专科','高中':'高中'}" headerKey="" headerValue="请选择"></s:select><s:submit value="查询"></s:submit></s:form></td>

javabean方法实现

public String queryCondition(){List<User> users =s.findUserByCondition(this);ActionContext.getContext().put("users", users);// #usersreturn SUCCESS;}

service层方法实现

public List<User> findUserByCondition(User user) {boolean ok1 = true;boolean ok2 = true;boolean ok3 = true;StringBuffer sb = new StringBuffer("where 1=1 ");if(user.getUsername()!=null&&!user.getUsername().equals("")){ok1 = false;sb.append(" and username like '%"+user.getUsername()+"%' ");}if(user.getSex()!=null&&!user.getSex().equals("")){ok2 = false;sb.append(" and sex='"+user.getSex()+"'");}if(user.getEducation()!=null&&!user.getEducation().equals("")){ok3 = false;sb.append(" and education='"+user.getEducation()+"'");}boolean conditionOk = ok1&&ok2&&ok3;//如果为false，说明至少有一个查询条件if(conditionOk){
//          System.out.println("没有查询条件");
//          return null;return dao.findUsersByCondition(null);}else{
//          System.out.println("有查询条件");
//          System.out.println(sb.toString());
//          return null;return dao.findUsersByCondition(sb.toString());}}