本文实例为大家分享了SpringMVC文件下载的具体代码,供大家参考,具体内容如下
两个案例
1.为登录用户提供下载服务。
2.阻止仅通过输入网址即可获取下载。
文件下载概览
为了将文件发送给浏览器,我们需要在控制器中完成以下操作:
案例1:为登录用户提供下载服务
Domain类
package domain; public class Login { private String username; private String password; 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; } }
Controller控制器
package controller; import domain.Login; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.web.bind.annotation.ModelAttribute; import org.springframework.web.bind.annotation.RequestMapping; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import java.io.*; @Controller public class ResourceController { private static final Log logger = LogFactory.getLog(ResourceController.class); @RequestMapping(value = "/login") public String login(@ModelAttribute Login login, HttpSession session, Model model) { model.addAttribute("login",new Login()); if("ms".equals(login.getUsername())&&"123".equals(login.getPassword())) { session.setAttribute("loggedIn",Boolean.TRUE); return "Main"; } else { return "LoginForm"; } } @RequestMapping(value = "/resource_download") public String downloadResource(HttpSession session, HttpServletRequest request, HttpServletResponse response) { if(session==null||session.getAttribute("loggedIn")==null) { return "LoginForm"; } String dataDirectory = request.getServletContext().getRealPath("/WEB-INF/data"); File file = new File(dataDirectory,"Blog.zip"); if(file.exists()) { response.setContentType("application/octet-stream"); response.addHeader("Content-Disposition","attachment;filename=Blog.zip"); byte[] buffer = new byte[1024]; FileInputStream fis =null; BufferedInputStream bis =null; try { fis = new FileInputStream(file); bis = new BufferedInputStream(fis); OutputStream os =response.getOutputStream(); int i =bis.read(buffer); while (i!=-1) { os.write(buffer, 0, i); i=bis.read(buffer); } } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); }finally { try { bis.close(); } catch (IOException e) { e.printStackTrace(); } try { fis.close(); } catch (IOException e) { e.printStackTrace(); } } } return null; } }
编写视图
Main.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>DownPage</title> </head> <body> <h5>点击链接下载文件</h5> <p> <a href="resource_download" rel="external nofollow" >Down</a> </p> </body> </html>
LoginForm.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>登录页面</title> </head> <body> <form:form commandName="login" action="login" method="post"> 账号: <br> <form:input path="username" cssErrorClass="error" id="username"/> <br> 密码: <br> <form:input path="password" cssErrorClass="error" id="password"/> <br> <input type="submit" value="提交"> </form:form> </body> </html>
案例2:阻止仅通过输入网址即可获取下载
@RequestMapping(value = "/resource_download") public String downloadResource(HttpSession session, HttpServletRequest request, HttpServletResponse response,@RequestHeader String refuer ){ if(refer==null) //通过判断refer来浏览器输入网址就能下载图片的情况 { return "LoginForm"; } String dataDirectory = request.getServletContext().getRealPath("/WEB-INF/data"); File file = new File(dataDirectory,"Blog.zip"); if(file.exists()) { response.setContentType("application/octet-stream"); response.addHeader("Content-Disposition","attachment;filename=Blog.zip"); byte[] buffer = new byte[1024]; FileInputStream fis =null; BufferedInputStream bis =null; try { fis = new FileInputStream(file); bis = new BufferedInputStream(fis); OutputStream os =response.getOutputStream(); int i =bis.read(buffer); while (i!=-1) { os.write(buffer, 0, i); i=bis.read(buffer); } } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); }finally { try { bis.close(); } catch (IOException e) { e.printStackTrace(); } try { fis.close(); } catch (IOException e) { e.printStackTrace(); } } } return null; } }
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持亿速云。
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