项目中用到了导出数据到excel的功能，特此记录一下
 
Pom
 
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>3.15</version>
        </dependency>
 
Controller层
 
  @RequestMapping(value = "/Export", method = RequestMethod.GET)
    public void Export(QueryCondition queryCondition, HttpServletResponse response) throws IOException {
        String fileName = "my.xls";
        response.setHeader("content-type", "application/octet-stream");
        response.setHeader("Content-Disposition", "attachment; filename=" + fileName);
        HSSFWorkbook workbook = myService.export(queryCondition);
        workbook.write(response.getOutputStream());
    }
 
Service层
 
    /**
     * 导出数据
     *
     * @param queryCondition 查询条件
     * @return HSSFWorkbook工作表
     */
    HSSFWorkbook export(QueryCondition queryCondition);
 
ServiceImpl层
 
 @Override
    public HSSFWorkbook export(QueryCondition queryCondition) {
        List<MyValue> myValues = this.queryMyValue(queryCondition);

        //创建一个excel
        HSSFWorkbook workbook = new HSSFWorkbook();
        //创建sheet
        //新建一个sheet页
        HSSFSheet sheet = workbook.createSheet("sheet1");

        //合并第一行的十个单元格
		CellRangeAddress cra1 = new CellRangeAddress(0, 0, 0, 10);
        sheet.addMergedRegion(cra1);
        HSSFCell titleCell = sheet.createRow(0).createCell(0);
        String title = "占了第一行十个单元格的值";
        titleCell.setCellValue(title);

		/**列表数据的标头*/
        HSSFRow titleRow = sheet.createRow(1);
        titleRow.createCell(0).setCellValue("序号");
        titleRow.createCell(1).setCellValue("角色");
        titleRow.createCell(2).setCellValue("姓名");
        titleRow.createCell(3).setCellValue("时间");
        titleRow.createCell(4).setCellValue("平均值");

        int i = 2;
        for (MyValue item : myValues) {
            HSSFRow row = sheet.createRow(i);
            row.createCell(0).setCellValue(item.getID());
            row.createCell(1).setCellValue(item.getUserType());
            row.createCell(2).setCellValue(item.getName());
            row.createCell(3).setCellValue(DateUtils.toString(item.getCreateTime()));
            row.createCell(4).setCellValue(DoubleUtils.toString(item.getAvgValue()));

            i++;
        }
        return workbook;
    }

网上介绍的方法都挺好，网上一搜也一大把，我用的是制作模板的那个方法，还挺好用的，现在分享一下。
 
先找一个教程，制作一个模板，然后就是测试：
 
代码它来了，
 
public class WordTest {  
      
    private Configuration configuration = null;  
      
    public WordTest(){  
        configuration = new Configuration();  
        configuration.setDefaultEncoding("UTF-8");  
    }  
      
    public static void main(String[] args) {  
        WordTest test = new WordTest();  
        test.createWord();  
    }  
      
    public void createWord(){  
        Map<String,Object> dataMap=new HashMap<String,Object>();  
        getData(dataMap);  
        configuration.setClassForTemplateLoading(this.getClass(), "");//模板文件所在路径
        Template t=null;  
        try {  
            t = configuration.getTemplate("测试.ftl"); //获取模板文件
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
        File outFile = new File("D:/outFile"+Math.random()*10000+".doc"); //导出文件
        Writer out = null;  
        try {  
            out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(outFile)));  
        } catch (FileNotFoundException e1) {  
            e1.printStackTrace();  
        }  
           
        try {  
            t.process(dataMap, out); //将填充数据填入模板文件并输出到目标文件 
        } catch (TemplateException e) {  
            e.printStackTrace();  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
    }  
  
    private void getData(Map<String, Object> dataMap) {  
        dataMap.put("title", "标题");  
        dataMap.put("nian", "2016");  
        dataMap.put("yue", "3");  
        dataMap.put("ri", "6");   
        dataMap.put("shenheren", "lc");  
          
        List<Map<String,Object>> list = new ArrayList<Map<String,Object>>();  
        for (int i = 0; i < 10; i++) {  
            Map<String,Object> map = new HashMap<String,Object>();  
            map.put("xuehao", i);  
            map.put("neirong", "内容"+i);  
            list.add(map);  
        }  
          
          
        dataMap.put("list", list);  
    }  
}
 
 
 
成了。
 
还可以直接输出到浏览器。
 
只需要添加
 
 
 
response.setContentType("application/x-msdownload;");
 response.addHeader("Content-Disposition", "attachment;filename="+ URLEncoder.encode("文件名", "UTF-8") + ".doc");
 
然后其中的createWord()方法就成了下面这个代码：
 
 public void createWord(HttpServletResponse resp){  
        Map<String,Object> dataMap=new HashMap<String,Object>();  
        getData(dataMap);  
        configuration.setClassForTemplateLoading(this.getClass(), "");//模板文件所在路径
        Template t=null;  
        try {  
            t = configuration.getTemplate("测试.ftl"); //获取模板文件
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
        //File outFile = new File("D:/outFile"+Math.random()*10000+".doc"); //导出文件
        Writer out = null; 
        response.setContentType("application/vnd.ms-excel");  
        response.addHeader("Content-Disposition", "attachment;filename="+ URLEncoder.encode("文件名", "UTF-8") + ".doc"); 
        try {  
            //out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(outFile)));  
              out = new BufferedWriter(new OutputStreamWriter(response.getOutputStream()));  
        } catch (FileNotFoundException e1) {  
            e1.printStackTrace();  
        }  
           
        try {  
            t.process(dataMap, out); //将填充数据填入模板文件并输出到目标文件 
        } catch (TemplateException e) {  
            e.printStackTrace();  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
    }  
  

正常 从ftp 拿文件 有可能根据 不同的浏览器 导致 直接预览文件 那么怎么避免呢，走后台 走输出流
 
 
 
            response.reset();
            response.setHeader("Pragma", "public");
            response.setHeader("Cache-Control", "public");
            response.setContentType("application/octet-stream");
            response.setHeader("Content-Disposition", "attachment;filename = " + pdfFileName);
 
这样就可以生成一个文件 给浏览器

第一种方式
 
//设置response的使用utf-8
response.setCharacterEncoding("utf-8");
//通知浏览器使用utf-8解码
response.setHeader("Content-Type", "text/html;charset=utf-8");
 
第二种方式（通常使用第二种）
 
response.setContentType("text/html;charset=utf-8");