java 将查询的数据导出成excel文件
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2024-03-20 21:27:40
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controller 层代码
/**
* 导出excel
* @param globalId
* @param createTime
*/
@GetMapping("/Export")
public void findSignDataExport(String globalId, String createTime, HttpServletRequest request, HttpServletResponse response){
applyService.findSignDataExport(globalId, createTime,request,response);
}
serviceImpl 层代码
/**
* 根据 globalId、创建日期，查询报名信息并导出excel
* @param globalId
* @param createTime
*/
@Override
public void findSignDataExport(String globalId, String createTime, HttpServletRequest request, HttpServletResponse response) {
List<Map<String,String>> applyData = new ArrayList<>();
/**
* 先查询出所有报名表名，根据表名id 获取所有表中字段
*/
List<Signinfos> signinfoses = signinfosMapper.selectTableName(globalId);
for (int i= 0; i < signinfoses.size(); i ++){
List<String> fieldName = signparamMapper.findFieldName(signinfoses.get(i).getId());
/**
* 创建字符串缓冲池，将集合中的数据拼接成字符串到数据库中查询
*/
StringBuilder fields = new StringBuilder();
for (int j = 0; j < fieldName.size(); j++){
fields.append(fieldName.get(j));
if(j != fieldName.size()-1){
fields.append(",");
}
}
// 获取报名完整信息
List<Map<String, String>> applyData1 = signMapper.findApplyData(fields.toString(), signinfoses.get(i).getTableName());
/**
* 将数据用新的map接收
*/
for (int j=0; j < applyData1.size(); j++){
Set<Map.Entry<String, String>> entries = applyData1.get(j).entrySet();
Iterator<Map.Entry<String, String>> iterator = entries.iterator();
Map<String,String> map = new HashMap<>(16);
while(iterator.hasNext()){
Map.Entry<String, String> next = iterator.next();
switch (next.getKey()){
case "Id":
map.put("0",next.getValue());
break;
case "CreateTime":
map.put("1",next.getValue());
break;
case "Status":
map.put("2",String.valueOf(next.getValue()));
break;
default:
map.put(next.getKey(),next.getValue());
}
}
applyData.add(map);
}
}
List<Map<String, String>> list = new ArrayList<>();
List<String> titleName = new ArrayList<>();
for (int i = 0; i < applyData.size(); i++){
int index = 0;
if(i == 0){
Map<String, String> stringStringMap = applyData.get(i);
Set<Map.Entry<String, String>> entries = stringStringMap.entrySet();
Iterator<Map.Entry<String, String>> iterator = entries.iterator();
while (iterator.hasNext()){
Map.Entry<String, String> next = iterator.next();
switch (next.getKey()){
case "0":
titleName.add("序号");
break;
case "1":
titleName.add("开始日期");
break;
case "2":
titleName.add("状态");
break;
default:
titleName.add(next.getKey());
}
}
}
Map<String, String> stringStringMap = applyData.get(i);
Map<String,String> newMap = new HashMap<>(16);
Set<Map.Entry<String, String>> entries = stringStringMap.entrySet();
Iterator<Map.Entry<String, String>> iterator = entries.iterator();
while (iterator.hasNext()){
Map.Entry<String, String> next = iterator.next();
newMap.put(String.valueOf(index),next.getValue());
index++;
}
list.add(newMap);
}
List<Title> paramName = signparamMapper.getParamName(globalId);
for (int i = 0; i < titleName.size(); i++ ){
for (int j = 0; j < paramName.size(); j++){
if(titleName.get(i).equals(paramName.get(j).getKey())){
titleName.set(i,titleName.get(i).replace(paramName.get(j).getKey(), paramName.get(j).getName()));
}
}
}
// excel标题
String[] title = new String[titleName.size()];
// 导出测评的结果
titleName.toArray(title);
// title = new String[] { "测评人姓名", "员工编号", "联系方式", "所属部门", "岗位类别", "测评问卷总数", "待填写测评数量" };
// 测评名称、测评时间
String evaluationName = "";
String evaluationTime = "";
String[][] content = new String[list.size()][title.length];
for (int i = 0; i < list.size(); i++) {
content[i] = new String[title.length];
Map<String, String> stringMap = list.get(i);
Set<Map.Entry<String, String>> set = stringMap.entrySet();
Iterator<Map.Entry<String, String>> iterator = set.iterator();
while(iterator.hasNext()){
Map.Entry<String, String> next = iterator.next();
content[i][Integer.valueOf(next.getKey())] = String.valueOf(next.getValue()) ;
}
}
// excel文件名
String fileName = "报名列表" + System.currentTimeMillis() + ".xls";
// sheet名
String sheetName = evaluationName + "_" + evaluationTime.split(" ")[0];
// 创建HSSFWorkbook
HSSFWorkbook wb = ExcelUtil.getHSSFWorkbook(sheetName, title, content, null);
// 响应到客户端
try {
this.setResponseHeader(response, fileName);
OutputStream os = response.getOutputStream();
wb.write(os);
os.flush();
os.close();
} catch (Exception e) {
e.printStackTrace();
}
}这个是抽取出来的公共方法
// 发送响应流方法
public void setResponseHeader(HttpServletResponse response, String fileName) {
try {
try {
fileName = new String(fileName.getBytes(), "ISO8859-1");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
response.setContentType("application/octet-stream;charset=ISO8859-1");
response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
response.addHeader("Pargam", "no-cache");
response.addHeader("Cache-Control", "no-cache");
} catch (Exception ex) {
ex.printStackTrace();
}
}接下来是工具类
package tide.jstv.operationdata.utils;
import org.apache.poi.hssf.usermodel.*;
public class ExcelUtil {
/**
* 导出Excel
*
* @param sheetName sheet名称
* @param title 标题
* @param values 内容
* @param wb HSSFWorkbook对象
* @return
*/
public static HSSFWorkbook getHSSFWorkbook(String sheetName, String[] title, String[][] values, HSSFWorkbook wb) {
// 第一步，创建一个HSSFWorkbook，对应一个Excel文件
if (wb == null) {
wb = new HSSFWorkbook();
}
// 第二步，在workbook中添加一个sheet,对应Excel文件中的sheet
HSSFSheet sheet = wb.createSheet(sheetName);
// 第三步，在sheet中添加表头第0行,注意老版本poi对Excel的行数列数有限制
HSSFRow row = sheet.createRow(0);
// 第四步，创建单元格，并设置值表头 设置表头居中
HSSFCellStyle style = wb.createCellStyle();
style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 创建一个居中格式
// 声明列对象
HSSFCell cell = null;
// 创建标题
for (int i = 0; i < title.length; i++) {
cell = row.createCell(i);
cell.setCellValue(title[i]);
cell.setCellStyle(style);
sheet.autoSizeColumn(i);
sheet.setColumnWidth(i, sheet.getColumnWidth(i) * 17 / 10);
}
// 创建内容
for (int i = 0; i < values.length; i++) {
row = sheet.createRow(i + 1);
for (int j = 0; j < values[i].length; j++) {
// 将内容按顺序赋给对应的列对象
row.createCell(j).setCellValue(values[i][j]);
}
}
return wb;
}
}
到这里就已经完成了