本文实例为大家分享了java文件上传和预览实现代码，供大家参考，具体内容如下
1、下载uploadify插件
2、index.html
<!DOCTYPE html> <html lang="en"> <head> <@head/> <script src="<@path/>/js/uploadify-v3.1/jquery.uploadify-3.1.js"></script> <link href="<@path/>/js/uploadify-v3.1/uploadify.css" rel="stylesheet" type="text/css" /> <style type="text/css"> #uploader { position: relative; } #uploader_queue { position: absolute; width: 600px; left: 200px; top: 0; } </style> <script type="text/javascript"> $(function() { $("#file_upload") .uploadify( { 'auto' : false, 'method' : "get", 'formData' : { 'folder' : 'file' }, 'height' : 30, 'swf' : '<@path/>/js/uploadify-v3.1/uploadify.swf', // flash 'uploader' : '<@path/>/uploadAttach.do', // 'width' : 120, 'fileTypeDesc' : 'ֻ支持多种文件格式', 'fileTypeExts' : '.dat;.264;.h264;.mp4;.dav;.MP4;.AVI;.ts;.avi;' + '.mpg;.rmvb;.flv;.rm;.mov;.wmv;.JPG;.bmp;.png;.BMP;.jpg;.PNG;' + '.gif;.xlsx;.xls;.txt;.pdf;.doc;.docx;.rar;.zip;.7z', 'fileSizeLimit' : '800KB', 'buttonText' : '选择文件', 'uploadLimit' : 5, 'successTimeout' : 5, 'requeueErrors' : false, 'removeTimeout' : 10, 'removeCompleted' : false, 'queueSizeLimit' : 10, 'queueID' : 'uploader_queue', 'progressData' : 'speed', 'onInit' : function() { }, 'onUploadSuccess' : function(file, data, response) { $("#uploader_view").append( '<img height="60" alt="" src="<@path/>/upload/' + encodeURI(data) + '"/><br/><br/>'); }, 'onQueueComplete' : function(queueData) { $('#uploader_msg').html( queueData.uploadsSuccessful + '个文件上传成功<br/>'); } }); }); </script> </head> <body> <@header/> <br /> <br /> <br /> <br /> <div id="uploader"> <p> <input type="file" name="file_upload" id="file_upload" /> </p> <a href="javascript:$('#file_upload').uploadify('upload','*')">上传</a> <a href="javascript:$('#file_upload').uploadify('stop')">取消上传</a> <div id="uploader_queue"></div> <div id="uploader_msg"></div> <div id="uploader_view"></div> </div> <br /> <br /> <br /> <br /> <@footer/> </body> </html>
3、java文件
package com.frame.core.ctrl; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.PrintWriter; import java.util.Date; import java.util.Map; import java.util.UUID; import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.log4j.Logger; import org.springframework.stereotype.Controller; import org.springframework.ui.ModelMap; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.multipart.MultipartFile; import org.springframework.web.multipart.MultipartHttpServletRequest; import org.springframework.web.servlet.ModelAndView; @Controller public class loginCtrl { private static Logger log = Logger.getLogger(loginCtrl.class); @RequestMapping(value = "/goindex") public ModelAndView goindex() { ModelAndView mav = new ModelAndView("index"); mav.addObject("name", "笑傲江湖"); mav.addObject("projectName", "Freemarker框架"); return mav; } @RequestMapping(value = "/login") public void login(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException { request.getSession().setAttribute("username", "身份认证成功"); request.getRequestDispatcher("/index.jsp").forward(request, response); } @RequestMapping("/uploadAttach") public void processUploadDir(ModelMap modelMap, MultipartHttpServletRequest request, PrintWriter writer) throws Exception { Map<String, MultipartFile> fileMap = request.getFileMap(); String path = request.getSession().getServletContext().getRealPath("/");; System.out.println("path:"+path); Date currentTime = new Date(); long prefix = currentTime.getTime(); StringBuffer attachIds = new StringBuffer(); for (Map.Entry<String, MultipartFile> f : fileMap.entrySet()) { MultipartFile file = f.getValue(); if (!isLegalFile(file)) { String msg = "is a illegal file"; throw new RuntimeException(msg); } String originalFileName = prefix + "_" + file.getOriginalFilename(); File fileDir = new File(path + "/upload" + File.separator); if (!fileDir.exists()) { fileDir.mkdirs(); } File files = new File(path + "/upload" + File.separator + originalFileName); FileOutputStream fileOutputStream = null; try { fileOutputStream = new FileOutputStream(files); fileOutputStream.write(file.getBytes()); fileOutputStream.flush(); attachIds.append(originalFileName + ","); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); } finally { if (fileOutputStream != null) { try { fileOutputStream.close(); } catch (IOException e) { e.printStackTrace(); } } } } writer.write(attachIds.toString().substring(0,attachIds.toString().length()-1)); } private final String[] fileType = new String[]{".dat",".264",".h264",".mp4",".dav",".MP4",".AVI",".ts",".avi",".mpg",".rmvb",".flv",".rm",".mov",".wmv", ".JPG",".bmp",".png",".BMP",".jpg",".PNG",".gif", ".xlsx",".xls",".txt",".pdf",".doc",".docx", ".rar",".zip",".7z"}; private boolean isLegalFile(MultipartFile file) { String originalFileName = file.getOriginalFilename(); for(String ft : fileType) { if (originalFileName.endsWith(ft)) { return true; } } return false; } }
效果图：
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查字典教程网。