工作需要写了一个POI的封装类,接受的数据类型是List
<settings>
<!-- 当返回值为LinkedHashMap时，表中存储的null值并不会存入Map中，因此还要在mybatis配置 -->
<setting name="callSettersOnNulls" value="true"/>
</settings>xml中写法
接受的数据类型是List<HashMap<String,Object>>,查询的字段顺序决定了列排列的顺序,如果不传入列名,使用List<HashMap<String,Object>>去取得列名,然后生成,
<select id="getexceldata" resultType="java.util.LinkedHashMap">
SELECT
ReportMonth, ExpenseNumber, Type, TotalActualExpenseAmount, RequesterNameCN,
RequesterEmployeeCode, Dept, Area, DeptConfirm, AreaConfirm, StartDate, EndDate,
ApprovalDate, AmountMonth, ApprovalNameCN, AccountantDate, AccountantDecision, AccountantNameCN,
InvoinceDate, Comments1, SysCreateDate, SysUpdateDate, OriginalId, BigBU
FROM t_ermonthlyreport
</select>/**
* POI导出方法类
*/
public class POIExcelExport {
/**
* 写入数据通用方法(导出多个sheet)
* @param workbook
* @param out : OutputStream对象
* @param limitNum : 超过limitNum生成新sheet
* @param sheetTitle : 设置excel的sheet标题
* @param headers : 设置excel的列标题
* @param columnsize : 设置excel的列宽度
* @param data : List<HashMap<String,Object>> 数据
* @throws IOException
*/
public void setExcelData(HSSFWorkbook workbook,OutputStream out,int limitNum,String sheetTitle,
String[] headers,int [] columnsize,List<LinkedHashMap<String,Object>> data) throws IOException{
int sheetNum = 0;
HSSFSheet sheet =null;
HSSFRow row = null;
//设置标题样式和单元格样式
HSSFCellStyle titlestyle = createTitleCellStyle(workbook);
HSSFCellStyle bodystyle = createBodyCellStyle(workbook);
int length = columnsize.length;
//遍历集合数据,产生数据行
if(data!=null){
int rowindex = 0;
for(HashMap<String,Object> entry:data){
if (rowindex % limitNum == 0){
if(rowindex != 0 ){
sheetNum++;
}
sheet = workbook.createSheet(sheetTitle+sheetNum);
//设置sheet的列宽
for(int i=0;i<length;i++){
sheet.setColumnWidth(i, (short)columnsize[i]*256);
}
row = sheet.createRow(0);
createHeaders(headers,titlestyle,row);
rowindex = 1;
}
row = sheet.createRow(rowindex);
int cellIndex = 0;
for (String key : headers){
HSSFCell cell = row.createCell(cellIndex);
cell.setCellStyle(bodystyle);
Object str = entry.get(key);
//处理空数据
if(str!=null ){
cell.setCellValue(str.toString());
}else{
cell.setCellValue(" ");
}
cellIndex++;
}
rowindex++;
}
}
}
/**
* 写入数据通用方法(导出多个sheet)重载
* headers 自己从HashMap中取
* @param workbook
* @param out : OutputStream对象
* @param limitNum : 超过limitNum生成新sheet
* @param sheetTitle : 设置excel的sheet标题
* @param columnsize : 设置excel的列宽度
* @param data : List<HashMap<String,Object>> 数据
* @throws IOException
*/
public void setExcelData(HSSFWorkbook workbook,OutputStream out,int limitNum,String sheetTitle,
int [] columnsize,List<LinkedHashMap<String,Object>> data) throws IOException{
int sheetNum = 0;
HSSFSheet sheet =null;
HSSFRow row = null;
//设置标题样式和单元格样式
HSSFCellStyle titlestyle = createTitleCellStyle(workbook);
HSSFCellStyle bodystyle = createBodyCellStyle(workbook);
int length = columnsize.length;
String [] headers = null;
//遍历集合数据,产生数据行
if(data!=null){
int rowindex = 0;
for(HashMap<String,Object> entry:data){
if (rowindex % limitNum == 0){
if(rowindex != 0 ){
sheetNum++;
}
sheet = workbook.createSheet(sheetTitle+sheetNum);
//设置sheet的列宽
for(int i=0;i<length;i++){
sheet.setColumnWidth(i, (short)columnsize[i]*256);
}
row = sheet.createRow(0);
headers =createHeaders(data,titlestyle,row);
rowindex = 1;
}
row = sheet.createRow(rowindex);
int cellIndex = 0;
for (String key : headers){
HSSFCell cell = row.createCell(cellIndex);
cell.setCellStyle(bodystyle);
Object str = entry.get(key);
//处理空数据
if(str!=null ){
cell.setCellValue(str.toString());
}else{
cell.setCellValue(" ");
}
cellIndex++;
}
rowindex++;
}
}
}
/**
* 导出excel通用方法(导出多个sheet .xls文件)重载
* @param workbook
* @param out : OutputStream对象
* @param limitNum : 超过limitNum生成新sheet
* @param sheetTitle : 设置excel的sheet标题
* @param headers : 设置excel的列标题
* @param columnsize : 设置excel的列宽度
* @param data : List<HashMap<String,Object>> 数据
* @throws IOException
*/
public void exprotExcelManySheet(HSSFWorkbook workbook,OutputStream out,int limitNum,String sheetTitle,
String[] headers,int [] columnsize,List<LinkedHashMap<String,Object>> data) throws IOException{
setExcelData(workbook, out, limitNum, sheetTitle, headers, columnsize, data);
workbook.write(out);
out.flush();
out.close();
}
/**
* 导出excel通用方法(导出多个sheet .xls文件)
* @param workbook
* @param out : OutputStream对象
* @param limitNum : 超过limitNum生成新sheet
* @param sheetTitle : 设置excel的sheet标题
* @param columnsize : 设置excel的列宽度
* @param data : List<HashMap<String,Object>> 数据
* @throws IOException
*/
public void exprotExcelManySheet(HSSFWorkbook workbook,OutputStream out,int limitNum,
String sheetTitle,int [] columnsize,List<LinkedHashMap<String,Object>> data) throws IOException{
setExcelData(workbook, out, limitNum, sheetTitle, columnsize, data);
workbook.write(out);
out.flush();
out.close();
}
/**
* 导出excel压缩包通用方法(导出多个sheet .zip文件)
* @param workbook
* @param limitNum : 限制每个sheet最多多少条数据
* @param sheetTitle : 每个sheet的name
* @param headers : sheet标题
* @param result : 传入的数据
* @param out
* @throws IOException
*/
public void exprotExcelManySheetZip(HSSFWorkbook workbook,OutputStream out,int limitNum,String sheetTitle,
String[] headers,int [] columnsize,List<LinkedHashMap<String,Object>> data) throws IOException{
setExcelData(workbook, out, limitNum, sheetTitle, headers, columnsize, data);
ZipOutputStream zip = new ZipOutputStream(out,Charset.forName("GBK"));
ZipEntry entry = new ZipEntry(sheetTitle+".xls");//设置压缩包中文件的名字
zip.putNextEntry(entry);
workbook.write(zip);
zip.flush();
zip.close();
}
/**
* 创建标题头
* @param headers
* @param titlestyle
* @param row
*/
public void createHeaders(String[] headers,HSSFCellStyle titlestyle,HSSFRow row){
int headerslength = headers.length;
for(int i =0;i<headerslength;i++){
HSSFCell cell = row.createCell(i);
HSSFRichTextString text = new HSSFRichTextString(headers[i]);
cell.setCellStyle(titlestyle);
cell.setCellValue(text.toString());
}
}
/**
* 创建标题头
* @param data
* @param titlestyle
* @param row
*/
public String [] createHeaders(List<LinkedHashMap<String,Object>> data,HSSFCellStyle titlestyle,HSSFRow row){
int size = data.get(0).size();
String [] headers = new String[size];
Set<String> keys = data.get(0).keySet();
Iterator iter = keys.iterator();
int count = 0;
while(iter.hasNext()){
String str = (String) iter.next();
headers[count] = str;
HSSFCell cell = row.createCell(count);
HSSFRichTextString text = new HSSFRichTextString(str);
cell.setCellStyle(titlestyle);
cell.setCellValue(text.toString());
count++;
}
return headers;
}
/**
* 设置正文单元格格式
* @param workbook
* @return
*/
public HSSFCellStyle createBodyCellStyle(HSSFWorkbook workbook){
HSSFCellStyle cellstyle = workbook.createCellStyle();
HSSFFont font = workbook.createFont();
font.setFontHeightInPoints((short)10);
font.setFontName(HSSFFont.FONT_ARIAL);
cellstyle.setFont(font);
cellstyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
return cellstyle;
}
/**
* 设置标题单元样式
* @param workbook
* @return
*/
public HSSFCellStyle createTitleCellStyle(HSSFWorkbook workbook){
HSSFCellStyle cellstyle = workbook.createCellStyle();
HSSFFont font = workbook.createFont();
font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
font.setFontHeightInPoints((short)10);
font.setFontName(HSSFFont.FONT_ARIAL);
cellstyle.setFont(font);
cellstyle.setFillForegroundColor(HSSFColor.SEA_GREEN.index);
cellstyle.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
cellstyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
return cellstyle;
}
/**
* excel 或者 zip 文件下载(表单提交,ajax请求不可以)
* @param request
* @param response
* @param filepath
* @param filename
* @param out
* @throws IOException
*/
public void download(HttpServletRequest request,HttpServletResponse response,HSSFWorkbook workbook,String sheetTitle,String filename) throws IOException {
// 以下主要实现 Excel文件下载
// 设置响应头和下载保存的文件名
response.reset();
response.setContentType("APPLICATION/OCTET-STREAM");
String xlsName ="ExpressCount.zip";
String excelName = URLEncoder.encode(xlsName, "UTF-8");
response.setHeader("Content-Disposition", "attachment; filename=\"" + excelName + "\"");
String path = request.getSession().getServletContext().getRealPath("upload/excelexport/");
String zipname ="ExpressCount";
FileInputStream fis = new FileInputStream(path+zipname+".zip");
// 写出流信息
int i = 0;
while ((i=fis.read()) != -1) {
response.getOutputStream().write(i);
}
fis.close();
response.getOutputStream().flush();
response.getOutputStream().close();
}
/**
* excel 或者 zip 文件流下载(表单提交,ajax请求不可以)
* @param path
* @param response
*/
public void downloadbyte(String path, HttpServletResponse response) {
try {
// path是指欲下载的文件的路径。
File file = new File(path);
// 取得文件名。
String filename = file.getName();
// 以流的形式下载文件。
InputStream fis = new BufferedInputStream(new FileInputStream(path));
byte[] buffer = new byte[fis.available()];
fis.read(buffer);
fis.close();
// 清空response
response.reset();
// 设置response的Header
response.addHeader("Content-Disposition", "attachment;filename="
+ new String(filename.getBytes()));
response.addHeader("Content-Length", "" + file.length());
OutputStream toClient = new BufferedOutputStream(
response.getOutputStream());
response.setContentType("application/vnd.ms-excel;charset=gb2312");
toClient.write(buffer);
toClient.flush();
toClient.close();
} catch (IOException ex) {
ex.printStackTrace();
}
}
}
/**
* POIExcelUtils工具类
*/
public class POIExcelUtils {
/**
* 导出多个sheet的excel(.xls文件)
* @param request
* @param result : List<HashMap<String,Object>> 数据
* @param filename : 导出excel的名字
* @param limitNum : 超过limitNum生成新sheet
* @param sheetTitle : 设置excel的sheet标题
* @param headers : 设置excel的列标题
* @param columnsize : 设置excel的列宽度
* @return
* @throws IOException
*/
public static String POIExcelExport(HttpServletRequest request,List<LinkedHashMap<String,Object>> result,String filename
,int limitNum,String sheetTitle,String [] headers,int[] columnsize) throws IOException{
POIExcelExport poiexport = new POIExcelExport();
HSSFWorkbook workbook = new HSSFWorkbook();
String path = request.getSession().getServletContext().getRealPath("upload/excelexport/");
//不存在就创建文件夹
newFolder(path);
OutputStream out = new FileOutputStream(path+filename);
poiexport.exprotExcelManySheet(workbook, out, limitNum, sheetTitle, headers, columnsize, result);
String downloadpath = "upload/excelexport/"+filename;
return downloadpath;
}
/**
* 导出多个sheet的excel(.xls文件)重载
* @param request
* @param result : List<HashMap<String,Object>> 数据
* @param filename : 导出excel的名字
* @param limitNum : 超过limitNum生成新sheet
* @param sheetTitle : 设置excel的sheet标题
* @param columnsize : 设置excel的列宽度
* @return
* @throws IOException
*/
public static String POIExcelExport(HttpServletRequest request,List<LinkedHashMap<String,Object>> result,
String filename,int limitNum,String sheetTitle,int[] columnsize) throws IOException{
POIExcelExport poiexport = new POIExcelExport();
HSSFWorkbook workbook = new HSSFWorkbook();
String path = request.getSession().getServletContext().getRealPath("upload/excelexport/");
//不存在就创建文件夹
newFolder(path);
OutputStream out = new FileOutputStream(path+"/"+filename);
poiexport.exprotExcelManySheet(workbook, out, limitNum, sheetTitle, columnsize, result);
String downloadpath = "upload/excelexport/"+filename;
return downloadpath;
}
/**
* 导出多个sheet的excel压缩文件(.zip)
* @param request
* @param result : List<HashMap<String,Object>> 数据
* @param filename : 导出excel的名字
* @param limitNum : 超过limitNum生成新sheet
* @param sheetTitle : 设置excel的sheet标题
* @param headers : 设置excel的列标题
* @param columnsize : 设置excel的列宽度
* @throws IOException
*/
public static String POIExcelExportZip(HttpServletRequest request,List<LinkedHashMap<String,Object>> result,String filename
,int limitNum,String sheetTitle,String [] headers,int[] columnsize) throws IOException{
POIExcelExport poiexport = new POIExcelExport();
HSSFWorkbook workbook = new HSSFWorkbook();
String path = request.getSession().getServletContext().getRealPath("upload/excelexport/");
//不存在就创建文件夹
newFolder(path);
OutputStream out = new FileOutputStream(path+filename);
poiexport.exprotExcelManySheetZip(workbook, out, limitNum, sheetTitle, headers, columnsize, result);
String zipdownloadpath = "upload/excelexport/"+filename;
return zipdownloadpath;
}
/**
* 传入的path不存在就创建文件夹
* @param path
* @return
*/
public static boolean newFolder(String path){
if(path == null || path==""){
return false;
}
File file = new File(path);
if(!file.exists()){
file.mkdirs();
}
return true;
}
/**
* 数据转换方法
* 暂没用到
* @param oldData
* @param keys
* @return
*/
public static List<List<Object>> dataTransfer(List<HashMap<String,Object>> oldData, String[] keys){
List<List<Object>> newData = new ArrayList<List<Object>>();
for (HashMap<String,Object> object : oldData) {
List<Object> row = new ArrayList<Object>();
for (String key : keys){
row.add(object.get(key));
}
newData.add(row);
}
return newData;
}
/**
* 从hashMap中拿到key的数组(暂时没用到)
* @param data
* @return
*/
public static String[] gethashMapKey(HashMap<String,Object> data){
int size = data.size();
String [] headers = new String[size];
Set<String> keys = data.keySet();
Iterator iter = keys.iterator();
int count = 0;
while(iter.hasNext()){
String str = (String) iter.next();
headers[count] = str;
count++;
}
return headers;
}
}
我在页面上用的Ajax请求,然后后台返回一个excel生成的地址,跳转就可以下载,如果想要通过流的方式,那么不可以用ajax,因为ajax无法解析流.
甚至可以传入List<List<String,Object>>类型
导出6万条数据时间15秒左右,如果不设置列的宽度,还要更快.我试过用poi自带的自适应方法,发现效率变低很多,但是不设置宽度导出的excel很难看,所以我手动传入一个列宽度的数组,在降低点效率的同时又做到了美观..