下载数据到Excel，工具类

使用反射将model数据下载到Excel中

package test.upload.utils;

import java.lang.reflect.Method;
import java.math.BigDecimal;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Map;

import org.apache.poi.hssf.usermodel.HSSFCell;
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.HSSFColor;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.CreationHelper;
import org.apache.poi.ss.usermodel.Font;
import org.apache.poi.ss.usermodel.Workbook;

/**
* 生成EXCEL的工具类
*
* @author duandingyang
*
*/
public class ExcelUtils {

/**
* 生成EXCEL的通用方法
*
* @param filePath 生成EXCEL的地址
* @param clazz 绑定数据的类型
* @param list 数据列表
* @param map EXCEL表头信息
* @throws Exception
*/
public static HSSFWorkbook generateExcel(Class<?> clazz, List<?> list,
Map<String, ExcelTitle> map) throws Exception {

HSSFWorkbook wb = new HSSFWorkbook();
CreationHelper helper = wb.getCreationHelper();
HSSFSheet sheet = wb.createSheet("sheet1");
HSSFRow row = sheet.createRow(0);
CellStyle cellStyle = ExcelUtils.createStyleCell(wb);
cellStyle.setFont(ExcelUtils.createFonts(wb));
int i = 0;
for (String attr : map.keySet()) {
sheet.setColumnWidth(i, 5000);
ExcelTitle excelTitle = map.get(attr);
int order = excelTitle.getOrder();
String title = excelTitle.getTitle();
HSSFCell cell = row.createCell(order);
cellStyle = ExcelUtils.setCellStyleAlignment(cellStyle, CellStyle.ALIGN_CENTER,
CellStyle.VERTICAL_CENTER);
cellStyle.setWrapText(true);
cell.setCellStyle(cellStyle);
cell.setCellValue(title);
i++;
}
int rowNum = 1;
if (list != null) {
for (Object obj : list) {
row = sheet.createRow(rowNum);
for (String attr : map.keySet()) {
ExcelTitle excelTitle = map.get(attr);
int order = excelTitle.getOrder();
Class<?> type = excelTitle.getType();
String getMethod = "get" + attr.substring(0, 1).toUpperCase()
+ attr.substring(1);
Method method = clazz.getMethod(getMethod, new Class[] {});
Object value = method.invoke(obj, new Object[] {});
HSSFCell cell = row.createCell(order);
if (value != null) {
if (Double.class.equals(type)) {
cellStyle = ExcelUtils.setCellStyleAlignment(cellStyle,
CellStyle.ALIGN_RIGHT, CellStyle.VERTICAL_CENTER);
cellStyle = ExcelUtils.setCellFormat(helper, cellStyle, "#,##0.00");
cell.setCellStyle(cellStyle);
double doubleValue = Double.valueOf(value.toString());
cell.setCellValue(doubleValue);
} else if (Long.class.equals(type)) {
cellStyle = ExcelUtils.setCellStyleAlignment(cellStyle,
CellStyle.ALIGN_CENTER, CellStyle.VERTICAL_CENTER);
cell.setCellStyle(cellStyle);
long longValue = Long.valueOf(value.toString());
cell.setCellValue(longValue);
} else if (String.class.equals(type)) {
// cellStyle = ExcelUtils.setCellStyleAlignment(cellStyle,
// CellStyle.ALIGN_CENTER, CellStyle.VERTICAL_CENTER);
// cell.setCellStyle(cellStyle);
cellStyle.setWrapText(true);
cell.setCellStyle(cellStyle);
cell.setCellValue(new HSSFRichTextString(value.toString()));
} else if (Date.class.equals(type)) {
// TODO 处理时间
SimpleDateFormat format=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String ctime = format.format(value);
cell.setCellValue(ctime);
}
else if (BigDecimal.class.equals(type)) {
BigDecimal bigDecimal=(BigDecimal) value;
String bigDecimalValue = bigDecimal.toString();
cell.setCellValue(bigDecimalValue);
}else if(Integer.class.equals(type)){
if(value != null){
cell.setCellValue(Integer.parseInt((value.toString())));
}
}
}
}
rowNum++;
}
}
return wb;
}

public static CellStyle createStyleCell(Workbook wb) {
CellStyle cellStyle = wb.createCellStyle();
// // 设置一个单元格边框颜色
// cellStyle.setBorderBottom(CellStyle.BORDER_THIN);
// cellStyle.setBorderTop(CellStyle.BORDER_THIN);
// cellStyle.setBorderLeft(CellStyle.BORDER_THIN);
// cellStyle.setBorderRight(CellStyle.BORDER_THIN);
// // 设置一个单元格边框颜色
// cellStyle.setRightBorderColor(IndexedColors.BLACK.getIndex());
// cellStyle.setLeftBorderColor(IndexedColors.BLACK.getIndex());
// cellStyle.setBottomBorderColor(IndexedColors.BLACK.getIndex());
// cellStyle.setTopBorderColor(IndexedColors.BLACK.getIndex());

return cellStyle;
}

/**
* 设置文字在单元格里面的位置 CellStyle.ALIGN_CENTER CellStyle.VERTICAL_CENTER
*
* @param cellStyle
* @param halign
* @param valign
* @return
*/
public static CellStyle setCellStyleAlignment(CellStyle cellStyle, short halign, short valign) {
// 设置上下
cellStyle.setAlignment(halign);
// 设置左右
cellStyle.setVerticalAlignment(valign);
return cellStyle;
}

/**
* 格式化单元格 如#,##0.00,m/d/yy去HSSFDataFormat或XSSFDataFormat里面找
*
* @param cellStyle
* @param fmt
* @return
*/
public static CellStyle setCellFormat(CreationHelper helper, CellStyle cellStyle, String fmt) {
// 还可以用其它方法创建format
cellStyle.setDataFormat(helper.createDataFormat().getFormat(fmt));
return cellStyle;
}

/**
* 设置字体
*
* @param wb
* @return
*/
public static Font createFonts(Workbook wb) {
// 创建Font对象
Font font = wb.createFont();
// 设置字体
font.setFontName("微软雅黑");
// 着色
font.setColor(HSSFColor.BLACK.index);
return font;
}

/**
* 生成EXCEL通用方法使用的表头类
*
* @author cuijianxing
*
*/
public static class ExcelTitle {

private int order;

private Class<?> type;

private String title;

public int getOrder() {
return order;
}

public void setOrder(int order) {
this.order = order;
}

public String getTitle() {
return title;
}

public void setTitle(String title) {
this.title = title;
}

public Class<?> getType() {
return type;
}

public void setType(Class<?> type) {
this.type = type;
}

public ExcelTitle(int order, Class<?> type, String title) {
super();
this.order = order;
this.type = type;
this.title = title;
}

}}

controller层：

@RequestMapping(value = "/downloadUserData", method = RequestMethod.GET)
public void downloadUserData(HttpServletRequest request,
HttpServletResponse response) {
response.setContentType("application/x-excel");
response.setHeader("content-disposition", "attachment;filename="
+ "UserData.xls");
response.setCharacterEncoding("UTF-8");
List<User> users = userService.getUserList();
Map<String, ExcelUtils.ExcelTitle> titleMap = this.getExcelTitleMap();
OutputStream ouputStream = null;
try {
HSSFWorkbook workBook = ExcelUtils.generateExcel(User.class, users,
titleMap);
ouputStream = response.getOutputStream();
workBook.write(ouputStream);
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
ouputStream.flush();
ouputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}

private Map<String, ExcelUtils.ExcelTitle> getExcelTitleMap() {
Map<String, ExcelUtils.ExcelTitle> titleMap = new HashMap<String, ExcelUtils.ExcelTitle>();

ExcelUtils.ExcelTitle excelTitle0 = new ExcelUtils.ExcelTitle(0,
String.class, "序号");
titleMap.put("id", excelTitle0);

ExcelUtils.ExcelTitle excelTitle1 = new ExcelUtils.ExcelTitle(1,
String.class, "姓名");
titleMap.put("name", excelTitle1);

ExcelUtils.ExcelTitle excelTitle2 = new ExcelUtils.ExcelTitle(2,
String.class, "电话");
titleMap.put("phone", excelTitle2);

ExcelUtils.ExcelTitle excelTitle3 = new ExcelUtils.ExcelTitle(2,
String.class, "地址");
titleMap.put("address", excelTitle3);

return titleMap; }

代码下载：
https://github.com/vincentduan/UploadExcel.git