java-SpringMVC框架导出Excel格式数据

1.控制层Controller，使用getLCCnsFeeCalMainExcel.do去接收

@SuppressWarnings("rawtypes")  //去除警告
@RequestMapping("getLCCnsFeeCalMainExcel.do")
public ModelAndView queryExcel(@RequestParam("req") String hreq)
throws ParseException, IOException, SQLException {
// 根据保单号查询其他信息
hreq = URLDecoder.decode(hreq,"UTF-8");
LCCnsFeeCalMainDto tLCCnsFeeCalMainDto = JsonUtils.toJsonObject(hreq,
LCCnsFeeCalMainDto.class);
List<Map> ptpList = tLCCnsFeeCalMainBlo.queryExcel(tLCCnsFeeCalMainDto);// 数据导出数据查询
String excelName = "LCCnsFeeCalMain.xls";// 创建生成文件的名字
LCCnsFeeCalMainViewExcel tLCCnsFeeCalMainViewExcel = new LCCnsFeeCalMainViewExcel(
excelName, ptpList);// 保单跟进文件生成方法
return new ModelAndView(tLCCnsFeeCalMainViewExcel);
}

2.LCCnsFeeCalMainViewExcel

     LCCnsFeeCalMainViewExcel类继承AbstractExcelView，调用构造方法及重写的buildExcelDocument方法

       构造方法：创建变量templetFilePath，内容为模板地址，并赋值，赋值过程在步骤3中展示

package com.yunhui.oversea.policy.view;
import java.io.BufferedOutputStream;
import java.io.OutputStream;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.springframework.web.servlet.view.document.AbstractExcelView;
import com.yunhui.oversea.policy.util.ExcelUtil;

public class LCCnsFeeCalMainViewExcel extends AbstractExcelView {
 String templetFilePath;
 String generateFilePath;
 Properties datas;
 @SuppressWarnings("rawtypes")
 List<Map> list;
    /***
     * 构造方法
     * @param generateFilePath
     * @param list
     */
 @SuppressWarnings("rawtypes")
 public LCCnsFeeCalMainViewExcel(String generateFilePath,List<Map> list) {
  //获取文件模板
  this.templetFilePath = System.getProperty("webServerRoot")+"/excel/LCCnsFeeCalMainView.xls";
  this.generateFilePath = generateFilePath;
  this.list = list;
 }
 
    /***
    * 向Excel表中写数据，生成对应的Excel文档
    */
 @Override
 protected void buildExcelDocument(Map<String, Object> arg0,
   HSSFWorkbook arg1, HttpServletRequest request,
   HttpServletResponse response) throws Exception {
  response.setContentType("application/vnd.ms-excel");
  response.setHeader("Content-disposition", "attachment;filename="
    + this.generateFilePath);
  ExcelUtil excel = new ExcelUtil(this.templetFilePath);
  excel.insertRow(1,this.list);
  
  OutputStream ouputStream = response.getOutputStream();
   BufferedOutputStream bos = new BufferedOutputStream(ouputStream);
  excel.wb.write(bos);
   bos.flush();    
   bos.close();
 }
}

      重写的buildExcelDocument：将参数使用ExcelUtil类，插入Excel表中，代码如下：

public void insertRow(int starRow,List<Map> list) throws IOException {

HSSFSheet sheet = this.wb.getSheetAt(0);
// 选择一个区域，从startRow+1直到最后一行
sheet.shiftRows(starRow + 1, sheet.getLastRowNum(), list.size(), true, false);

//System.out.println("starRow1:" + starRow);
starRow = starRow - 1;

for (int i = 0; i < list.size(); i++) {
HSSFRow sourceRow = null;
HSSFRow targetRow = null;
HSSFCell sourceCell = null;
HSSFCell targetCell = null;
short m;
starRow = starRow + 1;
sourceRow = sheet.getRow(starRow);

//System.out.println("starRow2:" + starRow);
if (sourceRow == null) {
sourceRow = sheet.createRow(starRow);
}
// 從start創建新的一行
targetRow = sheet.createRow(starRow + 1);
targetRow.setHeight(sourceRow.getHeight());
// sourceRow.setRowNum(sourceRow.getRowNum());
// 处理刚刚创建的一行
Map cellmap = (HashMap)list.get(i);
Object s[] = cellmap.keySet().toArray();
for(m = 0; m < cellmap.size(); m++) {
//for (m = sourceRow.getFirstCellNum(); m < cellList.size(); m++) {
sourceCell = sourceRow.getCell(m);
targetCell = targetRow.createCell(m);

// 风格一样
HSSFCellStyle style = wb.createCellStyle();
style.setBorderBottom(HSSFCellStyle.BORDER_THIN);
style.setBorderLeft(HSSFCellStyle.BORDER_THIN);
style.setBorderRight(HSSFCellStyle.BORDER_THIN);
style.setBorderTop(HSSFCellStyle.BORDER_THIN);

HSSFFont fontNormal = wb.createFont();
fontNormal.setFontHeightInPoints((short) 10);
fontNormal.setFontName("宋体");
fontNormal.setBoldweight(HSSFFont.BOLDWEIGHT_NORMAL);
style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 居中
style.setFont(fontNormal);

targetCell.setCellStyle(style);
//targetCell.setCellStyle(sourceCell.getCellStyle());
//targetCell.setCellType(sourceCell.getCellType());
String value = "";
if (cellmap.get(s[m]) != null)
{
if (cellmap.get(s[m]).getClass().equals(Timestamp.class)) {
Timestamp timestamp = (Timestamp) cellmap.get(s[m]);
Date date = new Date(timestamp.getTime());
value = DateUtils.format(date, DateUtils.FORMAT_LONG);
} else if (cellmap.get(s[m]).getClass().equals(BigDecimal.class)) {
value = StringUtils.twoDecimal(((BigDecimal) cellmap.get(s[m])).doubleValue());
} else {
value = cellmap.get(s[m]) + "";
}
}
targetCell.setCellType(HSSFCell.CELL_TYPE_STRING);
targetCell.setEncoding(HSSFCell.ENCODING_UTF_16);
targetCell.setCellValue(value);// 設置值
}
}
}

3.web.xml配置
        在tomcat下部署两个或多个项目时，web.xml文件中最好定义webAppRootKey参数，如果不定义，将会缺省为“webapp.root”，最好保证每个项目的参数值不同，以免引起项目冲突。

<!--   <context-param>
<param-name>webAppRootKey</param-name>
<param-value>webServerRoot</param-value>
</context-param>  -->

<listener>
    <listener-class>com.yunhui.oversea.policy.servlet.GeneralListener
</listener-class>
  </listener>

4.配置监听器GeneralListener类
       使用event.getServletContext().getRealPath("/")方法取得物理路径，并把其作为key和value放到system.properties系统属性中

public class GeneralListener implements ServletContextListener {

@Override
public void contextInitialized(ServletContextEvent event) {
String webServerRoot = event.getServletContext().getRealPath("/");
System.setProperty("webServerRoot", webServerRoot);
Properties properties = new Properties();
try
{
InputStream inputStream = Thread.currentThread().getContextClassLoader().getResourceAsStream("system.properties");
properties.load(inputStream);
inputStream.close(); //关闭流
}
catch (IOException e)
{
e.printStackTrace();
}
LogUtils.info(Log.BIZ_LOGGER, "webServerRoot:"+event.getServletContext().getRealPath("/"));

}

5.ModelAndView
        最后使用ModelAndView接收excel格式数据参数，并返回给前端展示
6.Excel文件导出成功