Java导出Excel（有数据库导出代码）

/**
* 导出
* @param request
* @param response
* @throws Exception
*/
@SuppressWarnings("unchecked")
@RequestMapping(value="vehicleMaintainExport.do")
public void exportVehicleMaintain(HttpServletRequest request,
HttpServletResponse response) throws Exception{

String param = request.getParameter("param");
JSONObject jsonObject = JSONObject.fromObject(param);

VehicleMaintainVo vehicleMaintainVo = (VehicleMaintainVo) JSONObject.toBean(jsonObject, VehicleMaintainVo.class);
String date = DateUtil.format(new Date(), DateUtil.YYYYMMDD);
// 获取输出文件的名字
String displayName = PropertiesManager.getProperty("export.vehicleMaintain.fileName")+date+".xls";
response.setContentType("application/vnd.ms-excel");
BufferedOutputStream out = null;
// 进行转码，使其支持中文文件名
response.addHeader("Content-Disposition", "attachment;filename="
+ new String(displayName.getBytes("UTF-8"), "iso-8859-1"));
try {
// 获取输出流
out = new BufferedOutputStream(response.getOutputStream());
} catch (FileNotFoundException e1) {
log.error(e1);
}
// 获取表格的表头字段名称
String gridHead = PropertiesManager.getProperty("export.vehicleMaintain.columnNames");
// 获取字段变量的名字
String fieldNames = PropertiesManager.getProperty("export.vehicleMaintain.fieldNames");
// 创建Excel
HSSFWorkbook wb = new HSSFWorkbook();
// 生成工作薄sheet(包含头信息)
HSSFSheet mainSheet = this.generateSheet(wb, displayName, gridHead);
// 设置数据样式
HSSFCellStyle normalDataStyle = wb.createCellStyle();
normalDataStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);

// 用户查询出来的总记录
long total = this.getTotal();
// 计算需要分批查询的次数
int eachQuerySize = Integer.parseInt(PropertiesManager.getProperty("export.excel.book.maxSheet"));
int no = (int) total / eachQuerySize + 1;
vehicleMaintainVo.setPageSize((int) total);
// 追加数据时,第几行
int rowNum = 0;
// 一行时,第几个单元格
int num = 0;
// 当前记录的数目
int currentRecordNum = 0;
int sheetNameIndex = 2;
int maxRow = Integer.parseInt(PropertiesManager.getProperty("export.excel.sheet.maxRow"));
for(int n=1;n<=no;n++){
vehicleMaintainVo.setPage(n);
Page page = vehicleMaintainService.pageQuery(vehicleMaintainVo);
List<VehicleMaintain>list = (List<VehicleMaintain>) page.getRows();
for(VehicleMaintain vm:list){
vm.setDeleteFlag(vm.getDeleteFlag().equals("0")?"未删除":"已删除");
if (currentRecordNum > maxRow) {
mainSheet = this.generateSheet(wb, displayName
+ sheetNameIndex, gridHead);
sheetNameIndex++;
currentRecordNum = 0;
rowNum = 0;
}
currentRecordNum++;
num = 0;
HSSFRow row = mainSheet.getRow(1 + rowNum);
if (row == null) {
row = mainSheet.createRow(1 + rowNum);
}
// Insert data
for (String field : fieldNames.split(",")) {
HSSFCell cell = row.getCell(num);
if (cell == null) {
cell = row.createCell(num);
}
cell.setCellStyle(normalDataStyle);
Field f = VehicleMaintain.class.getDeclaredField(field);
f.setAccessible(true);
Object value = f.get(vm);

this.setCellValue(cell, value);
num++;
}
rowNum++;
}
}

try {
wb.write(out);
out.flush();
} catch (Exception e) {
log.error(e);
}finally{
try {
out.close();
JCDFWebUtil.Log(request, "导出车辆安装维护,参数为:"+param);
} catch (IOException e) {
log.error(e);
}
}
}

/**
* 获取sheet
*
* @param wb
* @param sheetName 表格工作薄的名字
* @param gridHead 表格的表头字段名称
* @return
*/
private HSSFSheet generateSheet(HSSFWorkbook wb, String sheetName,
String gridHead) {
// 判断表头信息是否为空
if (null == gridHead) {
throw new RuntimeException("表头信息为空,无法导出!");
}
HSSFSheet mainSheet = wb.createSheet(sheetName);
// 设置标题sheet信息的样式
HSSFFont headFont = wb.createFont();
headFont.setFontHeightInPoints((short) 20);
headFont.setColor(HSSFFont.COLOR_RED);
HSSFCellStyle headStyle = wb.createCellStyle();
headStyle.setFont(headFont);

// 设置头信息的样式
HSSFFont titleFont = wb.createFont();
titleFont.setFontHeightInPoints((short) 8);
titleFont.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
titleFont.setColor(HSSFFont.COLOR_NORMAL);
HSSFCellStyle headerStyle = wb.createCellStyle();
headerStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
headerStyle.setFont(titleFont);

String[] gridList = gridHead.split(",");
// 创建第一行
HSSFRow headRow = mainSheet.createRow(0);

// 在第一行中添加头信息数据
int num = 0;
for (int i = 0; i < gridList.length; i++) {
String column = gridList[i];
// 创建单元格
HSSFCell headCell = headRow.createCell(num);
HSSFRichTextString h = new HSSFRichTextString(column);
headCell.setCellValue(h);
headCell.setCellStyle(headerStyle);
int columnWidth = 100;
mainSheet.setColumnWidth(num, columnWidth * 30);
num++;
}
return mainSheet;
}

private void setCellValue(HSSFCell cell, Object value) {
if (value instanceof java.lang.String) {
cell.setCellValue(new HSSFRichTextString(value.toString()));
} else if (value instanceof java.lang.Number) {
cell.setCellValue(Double.parseDouble(value.toString()));
} else if (value instanceof java.lang.Boolean) {
cell.setCellValue(Boolean.parseBoolean(value.toString()));
} else if (value instanceof java.util.Date) {
cell.setCellValue(DateUtil.format((Date) value,DateUtil.YYYY_MM_DD));
} else {
cell.setCellValue("");
}
}