Java对Excel表格的上传和下载处理方法
Excel表格文件的上传和下载,java中涉及到文件肯定会有io流的知识。
而excel文件就要涉及到poi技术,而excel的版本包括:2003-2007和2010两个版本, 即excel的后缀名为:xls和xlsx。
这里我是按照正规的项目流程做的案例,所以可能会比网上的一些Demo复杂一些。不过文件的上传和下载基本都是一套固定的流程,只是每个人的实现方式不太相同。
数据库我用的是MySql。
下面是我的项目目录:
按照正常的项目做了分层处理,文件上传的业务我放到了service处理,而文件下载业务还在controller层。
对前端请求处理,我分成了两个方法都放在HandleExcelController里面,这个类继承了BaseExcelController,基本的文件操作处理在BaseExcelController里面。
BaseExcelController继承了BaseController,BaseController类是所有controller的父类,这里用到的不太多,这个类封装了response返回值等的处理等一些方法。
项目中除了springMVC和mybatis的jar包之外还引入了:
上传和下载excel文件:
1、创建需要上传的excel文件,为了简化,我这里只写了四列,即四个字段
2、创建jsp页面
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>Excel文件处理</title> <script type="text/javascript" src="<c:url value='/res/js/jquery.js'/>"></script> <script> $(function(){ var $wrap = $(".wrap"); var find = function(str){ return $wrap.find(str); } var getJname = function(name){ return find("input[name='"+name+"']"); } getJname("Upload").click(function(){ var form = new FormData(document.getElementById("tf")); $.ajax({ url:"<c:url value='/File/UploadExcel'/>", type:"post", data:form, dataType:"json", processData:false, contentType:false, success:function(data){ //window.clearInterval(timer); if(data.success == "success"){ alert("提交文件成功,已将数据存入数据库"); } }, error:function(e){ alert("错误!"); //window.clearInterval(timer); } }); }) getJname("Download").click(function(){ $.post("<c:url value='/File/DownLoadExcel'/>",{"id":"3"},function(data){ //alert("下载文件成功"); },"json") }) }) </script> </head> <body> <div class="wrap"> <form id="tf"> <p> <input type="file" name="file" value="选择文件"/> Excel文件上传:<input type="button" name="Upload" value="upload"/> </p> <p> Excel文件下载:<input type="button" name="Download" value="updown"/> </p> </form> </div> </body> </html>
3、依次创建controller、service、domain、mapper层,注意它们的依赖关系
1)、controller层的处理,在HandleExcelController里面注入BaseExcelService。因为只是做个示范,所欲我这里将泛型固定为Students类
BaseExcelController代码:
package cn.wangze.controller; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.lang.reflect.Method; import java.text.SimpleDateFormat; import java.util.Collection; import java.util.Date; import java.util.Iterator; import java.util.List; import javax.servlet.http.HttpServletResponse; import org.apache.commons.lang.StringUtils; import org.apache.poi.hssf.usermodel.HSSFCell; import org.apache.poi.hssf.usermodel.HSSFCellStyle; import org.apache.poi.hssf.usermodel.HSSFFont; import org.apache.poi.hssf.usermodel.HSSFPalette; import org.apache.poi.hssf.usermodel.HSSFRichTextString; import org.apache.poi.hssf.usermodel.HSSFRow; import org.apache.poi.hssf.usermodel.HSSFSheet; import org.apache.poi.hssf.usermodel.HSSFWorkbook; import org.apache.poi.hssf.util.CellRangeAddress; import org.apache.poi.hssf.util.HSSFColor; import org.apache.poi.ss.usermodel.Sheet; import org.apache.poi.xssf.usermodel.XSSFWorkbook; import org.springframework.web.multipart.MultipartFile; import cn.wangze.domain.Students; public class BaseExcelController extends BaseController{ //获取文件的路径 String separator = System.getProperty("file.separator"); //验证元素是否为空 @SuppressWarnings("all") public boolean isEmpty(Object obj){ if(obj instanceof Object[]){ if(((Object[]) obj).length==0){ return true; } if(obj == null) return true; if((String.valueOf(obj).trim()).length() == 0){ return true; } if(obj instanceof List){ if(((List) obj) == null || ((List)obj).size() == 0){ return true; } } } return false; } /** * 文件上传部分 * */ //验证文件 protected boolean checkPathName(String fileName,HttpServletResponse response){ //验证文件是否存在 if(isEmpty(fileName)){ sendError("上传文件不存在",response); return false; } //验证文件是否是以xls或者xlsx做后缀的文件,如果不是就返回错误信息 if(!(StringUtils.endsWithIgnoreCase(fileName,".xls")||StringUtils.endsWithIgnoreCase(fileName, ".xlsx"))){ sendError("上传文件类型错误,请核对后重新上传?",response); } return true; } //获取文件的sheet protected Sheet getSheet(MultipartFile file,String path,String fileName) throws IllegalStateException, IOException{ //找到要存放到项目里面的路径,新建文件 File targetFile = new File(path, fileName); targetFile.mkdirs(); if (targetFile.exists()) { targetFile.delete(); file.transferTo(targetFile); } else { file.transferTo(targetFile); } //封装输入流,封装sheet里面的内容 InputStream is = null; try{ is = new FileInputStream(path+separator+fileName); //判断版本是否为Excel加强版 if(StringUtils.endsWithIgnoreCase(fileName, ".xls")){ return new HSSFWorkbook(is).getSheetAt(0); }else if(StringUtils.endsWithIgnoreCase(fileName, ".xlsx")){ return new XSSFWorkbook(is).getSheetAt(0); } return null; } finally{ if(is != null){ is.close(); } } } /** * 文件下载部分 * */ //根据传入的Sting值,判断生成在excel表的位置 private HSSFCellStyle getPublicStyle(HSSFWorkbook workbook,String key){ HSSFFont font = workbook.createFont(); HSSFCellStyle style = workbook.createCellStyle(); HSSFPalette customPalette = workbook.getCustomPalette(); customPalette.setColorAtIndex(HSSFColor.TEAL.index, (byte) 64, (byte) 148, (byte) 160); customPalette.setColorAtIndex(HSSFColor.ORANGE.index, (byte) 170, (byte) 204, (byte) 204); style.setAlignment(HSSFCellStyle.ALIGN_CENTER); style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER); if(key=="head"){ style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND); font.setFontHeightInPoints((short)12); font.setColor(HSSFColor.TEAL.index); font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD); style.setFont(font); } if(key=="title"){ font.setColor(HSSFColor.WHITE.index); font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD); style.setBorderLeft(HSSFCellStyle.BORDER_THIN); style.setLeftBorderColor(HSSFColor.WHITE.index); style.setBorderRight(HSSFCellStyle.BORDER_THIN); style.setRightBorderColor(HSSFColor.WHITE.index); style.setFont(font); style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND); style.setFillForegroundColor(HSSFColor.ORANGE.index); style.setFillBackgroundColor(HSSFColor.ORANGE.index); } return style; } //创建head头信息 private void createHead(HSSFSheet sheet,HSSFCellStyle style,String[] title){ HSSFRow row1 = sheet.createRow(0); HSSFCell cellTitle = row1.createCell(0); cellTitle.setCellValue(new HSSFRichTextString(title[0])); sheet.addMergedRegion(new CellRangeAddress(0,0,0,title.length-2)); cellTitle.setCellStyle(style); } //创建title信息 private void createTitle(HSSFSheet sheet,HSSFCellStyle style,String[] label,int columnNum){ HSSFRow row2 = sheet.createRow(1); HSSFCell cell1 = null; for(int n=0;n<columnNum;n++){ cell1 = row2.createCell(n); cell1.setCellValue(label[n+1]); cell1.setCellStyle(style); } } //创建content数据信息 private void createContent(HSSFSheet sheet,HSSFCellStyle style,Collection<Students> list,int columnNum,String[] parameters){ int index= 0; Iterator<Students> it = list.iterator(); while(it.hasNext()){ index++; Students cash = it.next(); int num2 = parameters.length; HSSFRow row = sheet.createRow(index+1); initCells(style, num2,cash, parameters,row); } } //验证是否为中文 public boolean checkChinese(String s){ int n=0; boolean flag =false; for(int i=0; i<s.length(); i++) { n = (int)s.charAt(i); flag=(19968 <= n && n <40623)?true:false; } return flag; } //将数据设置到excel表格内 public void initCells(HSSFCellStyle style, int columnNum, Students t, String[] endContent, HSSFRow row3) { for(int j=0;j<columnNum;j++){ HSSFCell cell = row3.createCell(j); String fieldName = endContent[j]; try{ if(fieldName!="" && !checkChinese(fieldName)){ String getMethodName = "get" +fieldName.substring(0,1).toUpperCase()+fieldName.substring(1); Class clazz = t.getClass(); Method getMethod = clazz.getMethod(getMethodName, new Class[]{}); String value = (String)getMethod.invoke(t, new Object[]{}); cell.setCellValue(value); }else{ cell.setCellValue(fieldName); } cell.setCellStyle(style); }catch(Exception e){ e.printStackTrace(); } } } public void createEnd(HSSFSheet sheet,HSSFCellStyle style,int numText,int columnNum,Students t,String[] endContent){ HSSFRow row3 = sheet.createRow(numText+2); initCells(style, columnNum, t, endContent, row3); } //根据service查询到的数据,创建excel表并插入查询的数据信息 protected String getOutputName(List<Students> list, String path, String[] title, String[] parameters, Students t, String[] endContent) throws IOException{ //根据传入的title数组的第一个值,设置文件名称 String filename = title[0]+"_"+ new SimpleDateFormat("yyyyMMdd").format(new Date())+".xls"; //输出流放到文件的本地位置 FileOutputStream fos = new FileOutputStream(path+separator+filename); //列数,根据title的个数,除去第一个就是每列title的信息 int columnNum = title.length-1; int numText = list.size(); HSSFWorkbook workbook = new HSSFWorkbook(); HSSFSheet sheet = workbook.createSheet(); sheet.setDefaultColumnWidth (20); sheet.setDefaultRowHeight((short)400); HSSFCellStyle contentStyle = this.getPublicStyle(workbook,""); HSSFCellStyle titleStyle = this.getPublicStyle(workbook,"title"); HSSFCellStyle headerStyle = this.getPublicStyle(workbook,"head"); createHead(sheet,headerStyle,title); createTitle(sheet,titleStyle,title,columnNum); createContent(sheet,contentStyle,list,columnNum,parameters); //createEnd(sheet,contentStyle,numText,columnNum,t,endContent); workbook.write(fos); fos.flush(); fos.close(); return filename; } }
HandleExcelController用来处理前端请求,代码如下:
package cn.wangze.controller; import java.io.File; import java.util.List; import javax.servlet.ServletOutputStream; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import org.apache.commons.io.FileUtils; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.multipart.MultipartFile; import cn.wangze.domain.Students; import cn.wangze.service.BaseExcelService; @Controller @RequestMapping("/File") public class HandleExcelController extends BaseExcelController{ @Autowired private BaseExcelService baseExcelService; @RequestMapping("/UploadExcel") public void UploadExcel(MultipartFile file,HttpSession session,HttpServletResponse response) throws Exception{ //如果上传的文件不存在,抛出异常 if(file == null){ throw new Exception("文件不存在"); } //获取文件名 String fileName = file.getOriginalFilename(); //选择上传的文件存放到项目的路径 String path = session.getServletContext().getRealPath(separator+"res"+separator+"upload"); if(!checkPathName(fileName,response)) return ; String msg = baseExcelService.loadExcel(getSheet(file, path, fileName)); sendMsg(true,msg,response); } @RequestMapping("/DownLoadExcel") public void UpdownExcel(Students student,HttpServletResponse res,HttpSession session,HttpServletResponse response) throws Exception{ List<Students> stus = baseExcelService.queryList(student); if(stus.size()==0){ res.sendRedirect("/index.jsp"); return; } //下载的excel文件存放的本地路径 String path = session.getServletContext().getRealPath(separator+"res"+separator+"exportExcel"+separator); ServletOutputStream os = res.getOutputStream(); Students t = baseExcelService.queryTotal(student); //标题文字,数值中的第一个值+当前日期为文件名称,以后的每个元素为每列的标题 String[] title={"studets04","id","名字","年龄","性别"};//标题文字 //对应实体类的属性值 String[] parameters ={"id","name","age","sex"}; String[] endContent = {"","","",""}; //调用父类的处理方法,生成excel文件 String filename = getOutputName(stus,path,title,parameters,t,endContent); try { res.reset(); res.setCharacterEncoding("utf8"); res.setContentType("application/vnd.ms-excel;charset=utf8"); res.setHeader("Content-Disposition", "attachment;fileName=" +new String(filename.getBytes("utf-8"),"iso-8859-1")); os.write(FileUtils.readFileToByteArray(new File(path+separator+filename))); sendResult(true,response); os.flush(); } finally { if (os != null) { os.close(); } } } }
2)、service层的处理,把StudentsMapper注入到BaseExcelService
BaseExcelService代码:
package cn.wangze.service; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import javax.servlet.ServletOutputStream; import javax.servlet.http.HttpSession; import org.apache.poi.ss.usermodel.Cell; import org.apache.poi.ss.usermodel.Row; import org.apache.poi.ss.usermodel.Sheet; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import cn.wangze.domain.Students; import cn.wangze.mapper.StudentsMapper; @Service public class BaseExcelService { @Autowired private StudentsMapper<Students> studentsMapper; //判断字符串是否为空 public boolean isEmpty(String str) { return str == null || str.length() == 0; } //获取单个表格(字段)存放的信息 private String getValue(Cell cell,String cellLable,Map<String,String> errMap){ cell.setCellType(Cell.CELL_TYPE_STRING); String value = cell.getStringCellValue().trim(); return value; } //通过这个方法将excel表的每行的数据放到info对象里面 private String addInfo(Row row,Students info){ Map<String,String> errMap = new HashMap<String,String>(); String id = getValue(row.getCell(0),"ID",errMap); String username = getValue(row.getCell(1),"姓名",errMap); String age = getValue(row.getCell(2),"年龄",errMap); String sex = getValue(row.getCell(3),"性别",errMap); String errMsg = errMap.get("errMsg"); if(!isEmpty(errMsg)){ return errMsg; } info.setId(id); info.setName(username); info.setAge(age); info.setSex(sex); return null; } public String loadExcel(Sheet sheet) throws Exception{ //新建一个List集合,用来存放所有行信息,即每行为单条实体信息 List<Students> infos = new ArrayList<Students>(); //获取到数据行数,第一行是title,不需要存入数据库,所以rowNum从1开始 for (int rowNum = 1; rowNum <= sheet.getLastRowNum(); rowNum++) { Students info = new Students(); String errMsg2 = addInfo(sheet.getRow(rowNum),info); if(errMsg2 != null) return errMsg2; infos.add(info); } if(infos.isEmpty()){ return "没有解析到学生数据,请查验EXCEL文件"; } //通过studentsMapper的insertSheetData方法,将实体类存放的数据插入到数据库 int result = studentsMapper.insertSheetData(infos); //若插入成功会返回大于1的整数,返回success if(result >= 1){ return "success"; } return "error"; } //查询所有数据库存放的学生信息 public List<Students> queryList(Students students){ return studentsMapper.queryList(students); } //获取到的学生实体信息 public Students queryTotal(Students students){ return studentsMapper.queryTotal(students); } public void downExcel(HttpSession session,String separator){ } }
3)、实体层的处理,字段要对应excel表的字段
package cn.wangze.domain; public class Students { String id; String name; String age; String sex; public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getAge() { return age; } public void setAge(String age) { this.age = age; } public String getSex() { return sex; } public void setSex(String sex) { this.sex = sex; } }
4)、dao层处理:StudentsMapper.java是一个接口,业务到数据库需要执行的方法在这里声明,StudentsMapper.xml相当于接口的实现类,用来连接java和数据库的操作。
StudentsMapper.java代码:
package cn.wangze.mapper; import java.util.List; public interface StudentsMapper<T> { public int insertSheetData(List<T> list); public List<T> queryList(T t); public T queryTotal(T t); }
StudentsMapper.xml代码:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="cn.wangze.mapper.StudentsMapper"> <sql id="ColumnList"> id,name,age,sex </sql> <sql id="ColumnList_t" > t.id,t.name,t.age,t.sex </sql> <sql id="ValueList"> #{id},#{name},#{age},#{sex} </sql> <sql id="WhereClause"> where 1=1 <if test="id!=null and id!=''">and id=#{id}</if> <if test="name!=null and name!=''">and name=#{name}</if> <if test="age!=null and age!=''">and age=#{age}</if> <if test="sex!=null and sex!=''">and sex=#{sex}</if> </sql> <sql id="WhereClause_pager" > where 1=1 <if test="t.id!=null and t.id!=''">and id=#{t.id}</if> <if test="t.name!=null and t.name!=''">and name=#{t.name}</if> <if test="t.age!=null">and age=#{t.age}</if> <if test="t.sex!=null and t.sex!=''">and sex=#{t.sex}</if> </sql> <sql id="SetClause" > set <trim suffixOverrides="," > <if test="id!=null">id=#{id},</if> <if test="name!=null">name=#{name},</if> <if test="pid!=null">age=#{age},</if> <if test="url!=null">sex=#{sex},</if> </trim> </sql> <select id="queryList" resultType="Students"> select <include refid="ColumnList"/> from students </select> <select id="queryTotal" parameterType="Students" resultType="Students"> select <include refid="ColumnList" /> from students <include refid="WhereClause"/> <!-- (select <include refid="ColumnList"/> from t_account_cash t <include refid="WhereClauseQuery"/> group by to_char(t.add_time,'yyyy-mm-dd'),t.account_id) a --> </select> <insert id="insertSheetData" useGeneratedKeys="true" parameterType="java.util.List"> <!-- <selectKey resultType="long" keyProperty="id" order="AFTER"> SELECT LAST_INSERT_ID() </selectKey> --> insert into students (id,name,age,sex) values <foreach collection="list" item="item" index="index" separator="," > (#{item.id},#{item.name},#{item.age},#{item.sex}) </foreach> </insert> </mapper>
所有的代码就是这些了,操作的时候需要注意的多是路径的问题。最复杂的就是BaseExcelController的操作,它做的事情就是解析上传和创建下载excel文件。
执行完之后的结果图是这样:
在数据库查看上传的excel表:
下载到D:\tomcat\tomcat6.0.32\webapps\ExcelHandleDemo\res\exportExcel文件夹下的excel表:
这里有一点不足的地方,我相信你已经发现了,就是下载完excel表格之后,前端还没有和业务对接上,没有相应的提示来告诉操作人执行结果,只能通过代码设置好的路径去查看文件夹下是否有下载的excel文件,
不过这都是细节问题,相信难不倒聪明的各位。
总结
以上所述是小编给大家介绍的Java对Excel表格的上传和下载处理方法,希望对大家有所帮助,如果大家有任何疑问欢迎给我留言,小编会及时回复大家的!