数据库表导出到excel

数据库表导出到excel:前置知识1 ALL_TAB_COLS
数据库表导出到excel:前置知识2 Quartz基本使用
数据库表导出到excel:前置知识3 项目封装的Quartz实现动态定时任务
数据库表导出到excel:前置知识4 业务和效果

	发起清单下载

control层InventoryDownloadLogController

/*
* 
*/
package com.njry.sjzl.busi.rest;

import com.njry.annotation.Log;
import com.njry.sjzl.busi.domain.InventoryDownloadLog;
import com.njry.sjzl.busi.service.InventoryDownloadLogService;
import com.njry.sjzl.busi.domain.vo.InventoryDownloadLogQueryCriteria;
import lombok.RequiredArgsConstructor;
import java.util.List;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.security.access.prepost.PreAuthorize;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.*;
import io.swagger.annotations.*;
import java.io.IOException;
import javax.servlet.http.HttpServletResponse;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.njry.utils.PageResult;

/**
* @author wj
* @date 2024-06-20
**/
@RestController
@RequiredArgsConstructor
@Api(tags = "清单任务下载表管理")
@RequestMapping("/api/inventoryDownloadLog")
public class InventoryDownloadLogController {

    private final InventoryDownloadLogService inventoryDownloadLogService;

    @Log("导出数据")
    @ApiOperation("导出数据")
    @GetMapping(value = "/download")
    @PreAuthorize("@el.check('inventoryDownloadLog:list')")
    public void exportInventoryDownloadLog(HttpServletResponse response, InventoryDownloadLogQueryCriteria criteria) throws IOException {
        inventoryDownloadLogService.download(inventoryDownloadLogService.queryAll(criteria), response);
    }


    @Log("下载文件")
    @ApiOperation("下载文件")
    @GetMapping(value = "/downloadFile")
    @PreAuthorize("@el.check('inventoryDownloadLog:list')")
    public void exportInventoryDownloadLogFile(HttpServletResponse response, InventoryDownloadLogQueryCriteria criteria) throws IOException {
        String attachmentId = criteria.getAttachmentId();
        inventoryDownloadLogService.downloadFile(attachmentId, response);
    }

    @GetMapping
    @Log("查询清单任务下载日志表")
    @ApiOperation("查询清单任务下载日志表")
    @PreAuthorize("@el.check('inventoryDownloadLog:list')")
    public ResponseEntity<PageResult<InventoryDownloadLog>> queryInventoryDownloadLog(InventoryDownloadLogQueryCriteria criteria, Page<Object> page){
        return new ResponseEntity<>(inventoryDownloadLogService.queryAll(criteria,page),HttpStatus.OK);
    }

    @PostMapping
    @Log("新增清单任务下载日志表--发起-----------调度任务异步把table数据变成文件")
    @ApiOperation("新增清单任务下载日志表--发起-----------调度任务异步把table数据变成文件")
    @PreAuthorize("@el.check('inventoryDownloadLog:add')")
    public ResponseEntity<Object> createInventoryDownloadLog(@Validated @RequestBody InventoryDownloadLog resources){
        inventoryDownloadLogService.create(resources);
        return new ResponseEntity<>(HttpStatus.CREATED);
    }

//    @PutMapping
//    @Log("修改清单任务下载日志表")
//    @ApiOperation("修改清单任务下载日志表")
//    @PreAuthorize("@el.check('inventoryDownloadLog:edit')")
//    public ResponseEntity<Object> updateInventoryDownloadLog(@Validated @RequestBody InventoryDownloadLog resources){
//        inventoryDownloadLogService.update(resources);
//        return new ResponseEntity<>(HttpStatus.NO_CONTENT);
//    }

    @DeleteMapping
    @Log("删除清单任务下载日志表")
    @ApiOperation("删除清单任务下载日志表")
    @PreAuthorize("@el.check('inventoryDownloadLog:del')")
    public ResponseEntity<Object> deleteInventoryDownloadLog(@RequestBody List<Long> ids) {
        inventoryDownloadLogService.deleteAll(ids);
        return new ResponseEntity<>(HttpStatus.OK);
    }
}

service层

/*
*
*/
package com.njry.sjzl.busi.service;

import com.njry.sjzl.busi.domain.InventoryDownloadLog;
import com.njry.sjzl.busi.domain.vo.InventoryDownloadLogQueryCriteria;
import java.util.Map;
import java.util.List;
import java.io.IOException;
import javax.servlet.http.HttpServletResponse;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.IService;
import com.njry.utils.PageResult;

/**
* @description 服务接口
* @author wj
* @date 2024-06-20
**/
public interface InventoryDownloadLogService extends IService<InventoryDownloadLog> {

    /**
    * 查询数据分页
    * @param criteria 条件
    * @param page 分页参数
    * @return PageResult
    */
    PageResult<InventoryDownloadLog> queryAll(InventoryDownloadLogQueryCriteria criteria, Page<Object> page);

    /**
    * 查询所有数据不分页
    * @param criteria 条件参数
    * @return List<InventoryDownloadLogDto>
    */
    List<InventoryDownloadLog> queryAll(InventoryDownloadLogQueryCriteria criteria);

    /**
    * 创建
    * @param resources /
    */
    void create(InventoryDownloadLog resources);

//    /**
//    * 编辑
//    * @param resources /
//    */
//    void update(InventoryDownloadLog resources);

    /**
    * 多选删除
    * @param ids /
    */
    void deleteAll(List<Long> ids);

    /**
    * 导出数据
    * @param all 待导出的数据
    * @param response /
    * @throws IOException /
    */
    void download(List<InventoryDownloadLog> all, HttpServletResponse response) throws IOException;

    /**
     * 导出文件
     * @param attachmentId 文件名
     * @param response /
     * @throws IOException /
     */
    void downloadFile(String attachmentId, HttpServletResponse response) throws IOException;

}

实现层impl(主要看create方法)

/*
*
*/
package com.njry.sjzl.busi.service.impl;

import cn.hutool.core.date.DateTime;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.njry.config.FileProperties;
import com.njry.sjzl.busi.attachment.domain.Attachment;
import com.njry.sjzl.busi.attachment.domain.vo.AttachmentQueryCriteria;
import com.njry.sjzl.busi.attachment.mapper.AttachmentMapper;
import com.njry.sjzl.busi.domain.Inventory;
import com.njry.sjzl.busi.domain.InventoryAuth;
import com.njry.sjzl.busi.domain.InventoryDownloadLog;
import com.njry.sjzl.busi.domain.vo.InventoryQueryCriteria;
import com.njry.sjzl.busi.mapper.AtomBusiCategoryMapper;
import com.njry.sjzl.busi.mapper.InventoryAuthMapper;
import com.njry.sjzl.busi.mapper.InventoryMapper;
import com.njry.sjzl.busi.task.GenerateExcelTask;
import com.njry.sjzl.busi.task.vo.TransferVo;
import com.njry.utils.*;
import lombok.RequiredArgsConstructor;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.njry.sjzl.busi.service.InventoryDownloadLogService;
import com.njry.sjzl.busi.domain.vo.InventoryDownloadLogQueryCriteria;
import com.njry.sjzl.busi.mapper.InventoryDownloadLogMapper;
import org.apache.poi.util.IOUtils;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.io.File;
import java.io.FileInputStream;
import java.sql.Timestamp;
import java.text.SimpleDateFormat;
import java.util.*;
import java.io.IOException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;

/**
* @description 服务实现
* @author wj
* @date 2024-06-20
**/
@Service
@RequiredArgsConstructor
public class InventoryDownloadLogServiceImpl extends ServiceImpl<InventoryDownloadLogMapper, InventoryDownloadLog> implements InventoryDownloadLogService {

    private final InventoryDownloadLogMapper inventoryDownloadLogMapper;

    private final InventoryMapper inventoryMapper;

    private final AttachmentMapper attachmentMapper;

    private final FileProperties properties;

    //    递归查询所属资产
    private final AtomBusiCategoryMapper atomBusiCategoryMapper;


    @Override
    public PageResult<InventoryDownloadLog> queryAll(InventoryDownloadLogQueryCriteria criteria, Page<Object> page){
        IPage<InventoryDownloadLog> all = inventoryDownloadLogMapper.findAll(criteria, page);
        List<InventoryDownloadLog> records = all.getRecords();
        //        根据每条数据类的busiSort递归向下查找归属业务分类(回显)
        if(records.size() > 0 ){
            for (int i = 0; i < records.size(); i++) {
                Set<String> taskSetResult  = new LinkedHashSet<>();
                Long categoryId = records.get(i).getCategoryId();
                if(categoryId != null){
                    List<String> subCategory = atomBusiCategoryMapper.findSubCategory(categoryId);
                    String currentCategoryName = atomBusiCategoryMapper.findCategoryNameByCateforyId(categoryId);
                    taskSetResult.addAll(subCategory);
                    taskSetResult.add(currentCategoryName);
                    String temp = "";
                    for(String item : taskSetResult){
                        temp += ","+item;
                    }
                    String result = temp.substring(1);
                    records.get(i).setCategoryName(result);
                }
            }
        }
        return PageUtil.toPage(all);
    }

    @Override
    public List<InventoryDownloadLog> queryAll(InventoryDownloadLogQueryCriteria criteria){
        return inventoryDownloadLogMapper.findAll(criteria);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void create(InventoryDownloadLog resources) {
//        前端发起只传inventoryId,别的基本数据这里查完赋值
        Long inventoryId = resources.getInventoryId();
        Inventory inventory = inventoryMapper.queryDetailByInventoryId(inventoryId);
        resources.setInventoryName(inventory.getInventoryName());
        resources.setCategoryId(inventory.getCategoryId());

//        新增的时候把操作人和操作时间
        Timestamp timestamp = DateTime.now().toTimestamp();
//        String username = "System";
//        try {username = SecurityUtils.getCurrentUsername();}catch (Exception ignored){}
//        操作人
        resources.setOperId(SecurityUtils.getCurrentUserId());
        resources.setOperDate(timestamp);
//        状态：0 待生成  2 正在生成  1 数据生成完成
        resources.setStatus(2);
//        正在生成没有附件id
        resources.setAttachmentId("");
        Long seq = inventoryDownloadLogMapper.getSeq();
        resources.setId(seq);
        save(resources);
//        异步生成文件(查询数据转成excel文件)


        Long currentUserId = SecurityUtils.getCurrentUserId();

//        获取系统定义的文件路径
        String dirPath = properties.getPath().getInventory();//系统文件路径下inventory
        String separator = properties.getPath().getSeparator();//获取系统分隔符
//        /inventory/日期/
        Date currentDate = new Date();
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM");
        String currentYearMonth = formatter.format(currentDate);
        System.out.println(currentYearMonth);
        dirPath += currentYearMonth + separator;


//        生成需要的参数加入队列
        TransferVo transferVo = new TransferVo();
        transferVo.setDirPath(dirPath);
        transferVo.setFileSuffix("xlsx");
        transferVo.setSeq(seq);
        transferVo.setInventoryId(inventoryId);
        transferVo.setSeparator(separator);
//        transferVo.setTableHead(tableHead);//费时间,放在异步里面
//        transferVo.setMaps(maps);//费时间,放在异步里面
        transferVo.setCurrentUserId(currentUserId);
        GenerateExcelTask.addDataList(transferVo);
    }

//    @Override
//    @Transactional(rollbackFor = Exception.class)
//    public void update(InventoryDownloadLog resources) {
//        InventoryDownloadLog inventoryDownloadLog = getById(resources.getId());
//        inventoryDownloadLog.copy(resources);
//        saveOrUpdate(inventoryDownloadLog);
//    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void deleteAll(List<Long> ids) {
        removeBatchByIds(ids);
    }

    @Override
    public void download(List<InventoryDownloadLog> all, HttpServletResponse response) throws IOException {
        List<Map<String, Object>> list = new ArrayList<>();
        for (InventoryDownloadLog inventoryDownloadLog : all) {
            Map<String,Object> map = new LinkedHashMap<>();
            map.put("唯一标识  序列", inventoryDownloadLog.getLogId());
            map.put("清单ID", inventoryDownloadLog.getInventoryId());
            map.put("清单名称", inventoryDownloadLog.getInventoryName());
            map.put("归属业务类别   T_atom_busi_category.CATEGORY_ID", inventoryDownloadLog.getCategoryId());
            map.put("操作人", inventoryDownloadLog.getOperId());
            map.put("操作时间", inventoryDownloadLog.getOperDate());
            map.put("状态：0 发起任务  2 正在生成  1 数据生成完成", inventoryDownloadLog.getStatus());
            map.put("附件编号", inventoryDownloadLog.getAttachmentId());
            map.put("提醒手机号码", inventoryDownloadLog.getMobile());
            list.add(map);
        }
        FileUtil.downloadExcel(list, response);
    }

    //        将文件转成响应流给前端
    @Override
    public void downloadFile(String attachmentId, HttpServletResponse response) throws IOException {
//        根据文件id查找文件所在位置   文件名
        String fileName = "";
        String dirPath = "";
        String separator = properties.getPath().getSeparator();//获取系统分隔符

        AttachmentQueryCriteria attachmentQueryCriteria = new AttachmentQueryCriteria();
        attachmentQueryCriteria.setAttachmentId(attachmentId);
        Attachment attachment = attachmentMapper.queryAllWithCondition(attachmentQueryCriteria);
        if(attachment != null){
            dirPath = attachment.getAttachmentPath();
            fileName = attachment.getFileName();
        }
//        因为保存的时候是在默认路径下加一个watermarkPath文件夹下生成同名的文件,这里取得时候也得取水印的文件
        String watermarkPath = dirPath + "watermarkPath" + separator;
        FileInputStream watermarkFileInput = null;
        //response为HttpServletResponse对象
        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=utf-8");
        //test.xls是弹出下载对话框的文件名，不能为中文，中文请自行编码
        response.setHeader("Content-Disposition", "attachment;filename=file.xlsx");
        ServletOutputStream out = response.getOutputStream();
        File watermarkFile = new File(watermarkPath, fileName);
        watermarkFileInput = new FileInputStream(watermarkFile);
        IOUtils.copy(watermarkFileInput,out);
        watermarkFile.deleteOnExit();
        watermarkFileInput.close();
    }
}

生成的文件位置

/*
 * 
 */
package com.njry.config;

import lombok.Data;
import com.njry.utils.ElConstant;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Configuration;

/**
 * @author njry
 */
@Data
@Configuration
@ConfigurationProperties(prefix = "file")
public class FileProperties {

    /** 文件大小限制 */
    private Long maxSize;

    /** 头像大小限制 */
    private Long avatarMaxSize;

    private ElPath mac;

    private ElPath linux;

    private ElPath windows;

    public ElPath getPath(){
//        System.getProperty() 方法用于获取系统属性的值
        String os = System.getProperty("os.name");
        if(os.toLowerCase().startsWith(ElConstant.WIN)) {
            return windows;
        } else if(os.toLowerCase().startsWith(ElConstant.MAC)){
            return mac;
        }
        return linux;
    }

    @Data
    public static class ElPath{

        private String path;

        private String avatar;

        private String inventory;

        private String separator;
    }
}

配置文件里写

# 文件存储路径
file:
  mac:
    path: ~/file/
    avatar: ~/avatar/
    inventory: /file/inventory/
    separator: /
  linux:
    path: /home/eladmin/file/
    avatar: /home/eladmin/avatar/
    inventory: /eladmin/file/inventory/
    separator: /
  windows:
    path: D:\sjzl\file\
    avatar: D:\sjzl\avatar\
#    inventory: D:\sjzl\file\inventory\ ## 不设置固定路径,相对路径自动找到项目所在盘位置
    inventory: \sjzl\file\inventory\
    separator: \
  # 文件大小 /M
  maxSize: 100
  avatarMaxSize: 5

mapper层

/*
* 
*/
package com.njry.sjzl.busi.mapper;

import com.njry.sjzl.busi.domain.InventoryDownloadLog;
import com.njry.sjzl.busi.domain.vo.InventoryDownloadLogQueryCriteria;
import java.util.List;
import java.util.Map;

import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Mapper;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;

/**
* @author wj
* @date 2024-06-20
**/
@Mapper
public interface InventoryDownloadLogMapper extends BaseMapper<InventoryDownloadLog> {

    IPage<InventoryDownloadLog> findAll(@Param("criteria") InventoryDownloadLogQueryCriteria criteria, Page<Object> page);

    List<InventoryDownloadLog> findAll(@Param("criteria") InventoryDownloadLogQueryCriteria criteria);

    List<String> findTableHead(@Param("tableName") String tableName,@Param("owner")  String owner);

    List<Map<String, Object>> commonSql(@Param("selectColumnSql") String selectColumnSql,@Param("tableName") String tableName,@Param("whereSql") String whereSql);

    Long getSeq();
}

xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.njry.sjzl.busi.mapper.InventoryDownloadLogMapper">
    <resultMap id="BaseResultMap" type="com.njry.sjzl.busi.domain.InventoryDownloadLog">
        <result column="LOG_ID" property="logId"/>
        <result column="LOG_ID" property="id"/>
        <result column="INVENTORY_ID" property="inventoryId"/>
        <result column="INVENTORY_NAME" property="inventoryName"/>
        <result column="CATEGORY_ID" property="categoryId"/>
        <result column="OPER_ID" property="operId"/>
        <result column="OPER_NAME" property="operName"/>
        <result column="OPER_DATE" property="operDate"/>
        <result column="STATUS" property="status"/>
        <result column="ATTACHMENT_ID" property="attachmentId"/>
        <result column="MOBILE" property="mobile"/>
    </resultMap>

    <sql id="Base_Column_List">
        LOG_ID, INVENTORY_ID, INVENTORY_NAME, CATEGORY_ID, OPER_ID, OPER_DATE, STATUS, ATTACHMENT_ID, MOBILE
    </sql>

    <sql id="Prefix_Base_Column_List">
        tidl.LOG_ID, tidl.INVENTORY_ID, tidl.INVENTORY_NAME, tidl.CATEGORY_ID, tidl.OPER_ID, tidl.OPER_DATE, tidl.STATUS, tidl.ATTACHMENT_ID, tidl.MOBILE
    </sql>

    <select id="findAll" resultMap="BaseResultMap">
        select tuser.name OPER_NAME,
        <include refid="Prefix_Base_Column_List"/>
        from T_INVENTORY_DOWNLOAD_LOG tidl
        left join T_USER tuser on tuser.user_id = tidl.OPER_ID
        <where>
            <if test="criteria.inventoryId != null">
                and tidl.INVENTORY_ID = #{criteria.inventoryId}
            </if>
            <if test="criteria.inventoryName != null">
                and tidl.INVENTORY_NAME like concat('%'||#{criteria.inventoryName},'%')
            </if>
            <if test="criteria.status != null">
                and tidl.STATUS = #{criteria.status}
            </if>
            <if test="criteria.mobile != null">
                and tidl.MOBILE = #{criteria.mobile}
            </if>
        </where>
    </select>

    <select id="findTableHead" resultType="java.lang.String">
        select a.column_name from all_tab_cols a
        where a.table_name=upper(#{tableName}) and owner=#{owner} order by a.column_id
    </select>

    <select id="commonSql" resultType="java.util.Map">
        select ${selectColumnSql} from ${tableName}
        <if test="whereSql != ''">
            where ${whereSql}
        </if>
    </select>


    <select id="getSeq" resultType="java.lang.Long">
        select  seq_T_INVENTORY_DOWNLOAD_LOG.nextval user_user_id from dual
    </select>
</mapper>

自己定义了一个任务调度然后可以启动调度
在这里插入图片描述

package com.njry.sjzl.busi.task;

import cn.hutool.core.date.DateTime;
import com.njry.sjzl.busi.attachment.domain.Attachment;
import com.njry.sjzl.busi.attachment.mapper.AttachmentMapper;
import com.njry.sjzl.busi.domain.Inventory;
import com.njry.sjzl.busi.domain.InventoryAuth;
import com.njry.sjzl.busi.domain.InventoryDownloadLog;
import com.njry.sjzl.busi.mapper.InventoryAuthMapper;
import com.njry.sjzl.busi.mapper.InventoryDownloadLogMapper;
import com.njry.sjzl.busi.mapper.InventoryMapper;
import com.njry.sjzl.busi.task.vo.TransferVo;
import com.njry.utils.GenerateExcelToFile;
import com.njry.utils.SecurityUtils;
import lombok.RequiredArgsConstructor;
import org.springframework.security.core.context.SecurityContext;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Service;

import java.io.IOException;
import java.sql.Timestamp;
import java.util.ArrayDeque;
import java.util.List;
import java.util.Map;
import java.util.Queue;

@Service
@RequiredArgsConstructor
public class GenerateExcelTask {

    /**
     * 定义一个队列
     */
    // 定义一个队列
    static Queue<TransferVo> queue = new ArrayDeque<>();

    private final AttachmentMapper attachmentMapper;

    private final InventoryDownloadLogMapper inventoryDownloadLogMapper;

    private final InventoryAuthMapper inventoryAuthMapper;

    private final InventoryMapper inventoryMapper;


    public static void addDataList(TransferVo transferVo){
        queue.offer(transferVo);
    }

    public static TransferVo pollDataList(){
        TransferVo poll = queue.poll();// poll 方法用于获取队列头部的元素并移除它
        return poll;
    }



    public void run(){
        System.out.println("在sjzl-busi下面的bean被任务调度");
//        异步生成excel
        try {
            TransferVo transferVo = GenerateExcelTask.pollDataList();
            System.out.println("取出一个数据后队列长度:"+queue.size());
            if(transferVo != null){
                String dirPath = transferVo.getDirPath();
//                List<Map<String, Object>> maps = transferVo.getMaps();
//                List<String> tableHead = transferVo.getTableHead();
                String fileSuffix = transferVo.getFileSuffix();
                Long seq = transferVo.getSeq();
                Long currentUserId = transferVo.getCurrentUserId();
                Long inventoryId = transferVo.getInventoryId();
                String separator = transferVo.getSeparator();
//        根据清单inventoryId和当前用户判断拥有的权限(要不要放where条件)  清单用户权限T_INVENTORY_AUTH
//        AUTH_TYPE  权限类别：1 全量 不放where  2 单元 (清单选择的列名和权限里的单元编号作为where条件)
//        AREA_ID    单元编号
                InventoryAuth inventoryAuth = inventoryAuthMapper.findByUserIdAndInventoryId(currentUserId, inventoryId);
                Inventory inventory = inventoryMapper.queryDetailByInventoryId(inventoryId);
                Integer authType = inventoryAuth.getAuthType();
                Long areaId = inventoryAuth.getAreaId();
                String whereSql = "";
                if(authType == 2){
                    String queryColName = inventory.getQueryColName();
                    whereSql = queryColName + "=" + areaId;
                }

                String tableName = inventory.getTableName();
//        tableName = "t_organization";//写死测试
//                tableName = "atom_base_info";//写死测试分sheet
//                whereSql = "";//写死测试(配置的列名称不对)
                String owner = "NJDATA";//从配置里读取

//        获取表的列名-------作为select  xxx,xxx,xxx,xxx from 表名
//        select a.column_name from all_tab_cols a
//        where a.table_name=upper('t_organization') and owner='NJDATA' order by a.column_id;
                List<String> tableHead = inventoryDownloadLogMapper.findTableHead(tableName, owner);
                String selectColumnSql = String.join(",",tableHead);

//      通用查询sql,传入查询字段,表名和where条件(区分#{}和${}的时候了)
                List<Map<String, Object>> maps = inventoryDownloadLogMapper.commonSql(selectColumnSql, tableName, whereSql);


//             将数据生成excel文件里面
                Map<String, Object> resultMap = GenerateExcelToFile.dataToExcel(maps, tableHead, dirPath, fileSuffix,separator);
                Attachment attachment = new Attachment();
//            将文件数据保存文件附件表 T_ATTACHMENT
                attachment.setAttachmentId(resultMap.get("attachmentId").toString());
                attachment.setFileName(resultMap.get("fileName").toString());
                attachment.setFileType(resultMap.get("fileType").toString());
                attachment.setFileExtension(resultMap.get("fileExtension").toString());
                attachment.setFileSize(resultMap.get("fileSize").toString());
                attachment.setAttachmentPath(resultMap.get("attachmentPath").toString());
                //        新增的时候把操作人和操作时间
                Timestamp timestampAgain = DateTime.now().toTimestamp();
                attachment.setOperDate(timestampAgain);
                //        操作人
//                SecurityContext context = SecurityContextHolder.getContext();
//                System.out.println("SecurityContext:这里可以获取到吗"+context);
//                attachment.setOperId(SecurityUtils.getCurrentUserId());
                attachment.setOperId(currentUserId);
                attachmentMapper.insert(attachment);
//            在文件生成记录T_INVENTORY_DOWNLOAD_LOG 修改文件生成状态 和添加附件编号
                InventoryDownloadLog inventoryDownloadLog = new InventoryDownloadLog();
                inventoryDownloadLog.setId(seq);
                inventoryDownloadLog.setAttachmentId(resultMap.get("attachmentId").toString());
                inventoryDownloadLog.setStatus(1);
                inventoryDownloadLogMapper.updateById(inventoryDownloadLog);

//            发送短信通知用户生成结束

            }else{
//            这里应该降低任务执行调度的频率
                System.out.println("暂时没有可以执行的生成文件");
            }

        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

工具类(将数据库数据转成file保存)

package com.njry.utils;

import cn.hutool.core.util.IdUtil;
import com.njry.config.FileProperties;
import com.njry.exception.BadRequestException;
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.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class GenerateExcelToFile {


    /**
     *
     * @param list  数据库查询出来的信息
     * @param tableHead  数据库的表头(简单表头)
     * @param dirPath  保存的文件路径
     * @param fileSuffix 生成的excel格式后缀
     * @param separator 生成的excel带水印格要多加一层文件路径
     * @throws IOException
     */
    public static Map<String, Object> dataToExcel(List<Map<String, Object>> list,List<String> tableHead,String dirPath, String fileSuffix, String separator) throws IOException {
        Map<String, Object> resultMap = new HashMap<>();
        Workbook wb = null;
        FileInputStream tempInput = null;
        String watermarkPath = dirPath + "watermarkPath" + separator;
        int type = 3;//默认用type区分一个sheet有多少行
        if("xlsx".equals(fileSuffix)){
            wb = new XSSFWorkbook();
            type = 1;
        }
        if("xls".equals(fileSuffix)){
            wb = new HSSFWorkbook();
            type = 2;
        }
        Workbook exportWorkbook = export(wb, list, tableHead, type);
        String attachmentId = IdUtil.simpleUUID();
        String fileSize = "";
        String to_file_name = attachmentId + "." + fileSuffix;	// 结果文件名称
//        判断保存的文件路径是否存在,不存在就创建
        File outFileExist = new File(dirPath);
        if(!outFileExist.exists()){
            outFileExist.mkdirs();
        }
        File outFile = new File(dirPath, to_file_name);
        try {
            FileOutputStream outStream = new FileOutputStream(outFile);
            // 写入Workbook到文件
            exportWorkbook.write(outStream);
//            也可以通过流获取大小
//            long size = outStream.getChannel().size();
            // 强制刷新文件流，确保所有数据都被写入到文件中
            outStream.flush();

            // 获取文件对象
            File outputFile = new File(dirPath, to_file_name);
            long length = outputFile.length();
            fileSize =  length  + " bytes";
            
            outStream.close();
        } catch (Exception e) {
            throw new BadRequestException("导出结果文件异常：" + e);
        }

//        将有数据的excel的文件再加水印
        File tempFile = new File(dirPath, to_file_name);
        tempInput = new FileInputStream(tempFile);
        XSSFWorkbook xSSFWorkbook = new XSSFWorkbook(tempInput);
//            将导出的数据加水印放到另一个文件watermarkPath里面
        File watermarkFileExist = new File(watermarkPath, to_file_name);
        PoiSecurity.addWatermarkToXlsx(new String[]{"test"},xSSFWorkbook,watermarkFileExist);
        xSSFWorkbook.close();
        tempInput.close();
        // 终止后删除临时文件
        tempFile.deleteOnExit();
//        处理文件信息返回
        resultMap.put("attachmentId",attachmentId);
        resultMap.put("fileName",to_file_name);
        resultMap.put("fileType","excel");
        resultMap.put("fileExtension",fileSuffix);
        resultMap.put("fileSize",fileSize);
        resultMap.put("attachmentPath",dirPath);
        return resultMap;
    }

    /**
     *
     * @param wb 操作的Workbook
     * @param list 数据库查询出来的信息
     * @param tableHead 数据库的表头(简单表头)
     * @param type excel类型  xlsx  1   xls 2   -------区分sheet最大告诉
     * @return
     */
    public static Workbook export(Workbook wb,List<Map<String, Object>> list, List<String> tableHead,int type) {
        HSSFWorkbook HSSwb = null;
        XSSFWorkbook XSSwb = null;
//        不定义sheet名字,自生成
//        Excel 2003及更早的版本中，行数上限是65,536行
//        2007开始，行数上限增加到了1,048,576行
        int maxRow = 49999;//去除一个表头行
        if(type == 1){
            maxRow = 1048575;//去除一个表头行
            XSSwb  = (XSSFWorkbook)wb;
        }

        if(type == 2){
            maxRow = 65535;//去除一个表头行
            HSSwb  = (HSSFWorkbook)wb;
        }
        maxRow = 49999;//去除一个表头行(无论啥格式默认都是50000一个sheet)
//        处理数据需要多少个sheet
        int size = list.size();
        int result = size / maxRow + 1;
        if(result == 0){
            result = 1;
        }
//        循环sheet
        for (int i = 0; i < result; i++) {
            
            if(type == 1){
                XSSFSheet sheet = XSSwb.createSheet();
                //            处理每个sheet的表头
                XSSFRow row = sheet.createRow((short) 0);
                Cell cell = null;
                for (int j = 0; j < tableHead.size(); j++) {
                    cell = row.createCell(j);
//                cell.setCellStyle(headStyle);
                    cell.setCellValue(tableHead.get(j));
                }
//          写入数据
                for (int n = 0 + maxRow * i; n < maxRow * (i + 1); n++) {
//                判断数据list的大小是否大于要创建的行
                    if(size - 1 >= n ){//下面list.get(n)就取不到数据,不应该继续创建行  size 14 get(n)时候 n只能到13
                        row = sheet.createRow(n % maxRow + 1);
                        Cell dataCell = null;
                        for (int m = 0; m < tableHead.size(); m++) {
                            dataCell = row.createCell(m);
                            dataCell.setCellValue(StringUtils.notEmpty(list.get(n).get(tableHead.get(m))));
                        }
                    }
                }
            }
            if(type == 2){
                HSSFSheet sheet = HSSwb.createSheet();
                //            处理每个sheet的表头
                HSSFRow row = sheet.createRow((short) 0);
                Cell cell = null;
                for (int j = 0; j < tableHead.size(); j++) {
                    cell = row.createCell(j);
//                cell.setCellStyle(headStyle);
                    cell.setCellValue(tableHead.get(j));
                }
//          写入数据
                for (int n = 0 + maxRow * i; n < maxRow * (i + 1); n++) {
//                判断数据list的大小是否大于要创建的行
                    if(size - 1 >= n ){//下面list.get(n)就取不到数据,不应该继续创建行  size 14 get(n)时候 n只能到13
                        row = sheet.createRow(n % maxRow + 1);
                        Cell dataCell = null;
                        for (int m = 0; m < tableHead.size(); m++) {
                            dataCell = row.createCell(m);
                            dataCell.setCellValue(StringUtils.notEmpty(list.get(n).get(tableHead.get(m))));
                        }
                    }
                }
            }

        }
        return wb;
    }
}

工具类PoiSecurity(之前贴过)

package com.njry.utils;

import java.awt.*;
import java.awt.font.FontRenderContext;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.io.*;
import java.security.GeneralSecurityException;

import javax.imageio.ImageIO;

import org.apache.poi.ooxml.POIXMLDocumentPart;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.openxml4j.opc.PackageAccess;
import org.apache.poi.openxml4j.opc.PackagePartName;
import org.apache.poi.openxml4j.opc.PackageRelationship;
import org.apache.poi.openxml4j.opc.TargetMode;
import org.apache.poi.poifs.crypt.EncryptionInfo;
import org.apache.poi.poifs.crypt.EncryptionInfoBuilder;
import org.apache.poi.poifs.crypt.EncryptionMode;
import org.apache.poi.poifs.crypt.Encryptor;
import org.apache.poi.poifs.crypt.binaryrc4.BinaryRC4EncryptionInfoBuilder;
import org.apache.poi.poifs.crypt.binaryrc4.BinaryRC4Encryptor;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.*;
import org.springframework.core.io.ClassPathResource;

public class PoiSecurity {

	public static void addWatermarkToXlsx(String[] content,XSSFWorkbook xssfworkbook,File outfile) throws IOException{
		ByteArrayOutputStream bytestream = createWaterMark(content,300,250);
//		XSSFWorkbook下面有几个sheet
		int sheetsize = xssfworkbook.getNumberOfSheets();
		for(int index=0;index<sheetsize;index++){
			XSSFSheet sheet = xssfworkbook.getSheetAt(index);
			XSSFWorkbook workbook = sheet.getWorkbook();
//			bytestream.toByteArray()(前置知识)
//			下面这一串看不懂(没看官网文档的下场)
	        int pictureIdx = workbook.addPicture(bytestream.toByteArray(), Workbook.PICTURE_TYPE_PNG);
	        POIXMLDocumentPart poixmlDocumentPart = workbook.getAllPictures().get(pictureIdx);
	        PackagePartName ppn = poixmlDocumentPart.getPackagePart().getPartName();
			String relType = XSSFRelation.IMAGES.getRelation();
			PackageRelationship pr = sheet.getPackagePart().addRelationship(ppn, TargetMode.INTERNAL, relType, null);
	        sheet.getCTWorksheet().addNewPicture().setId(pr.getId());
		}

		if(!outfile.exists()){
			File par = outfile.getParentFile();
			if(!par.exists()){
				par.mkdirs();
			}
			outfile.createNewFile();
		}
		FileOutputStream out = new FileOutputStream(outfile);
		xssfworkbook.write(out);
		out.close();
	}

	public static void addImageToXlsx(String[] content,XSSFWorkbook xssfworkbook,File outfile) throws IOException{
		int imgW = 300,imgH = 250;
		ByteArrayOutputStream bytestream = createWaterMark(content,imgW,imgH);
		byte[] bytes = bytestream.toByteArray();
		int sheetsize = xssfworkbook.getNumberOfSheets();
		for(int index=0;index<sheetsize;index++){
			XSSFSheet sheet = xssfworkbook.getSheetAt(index);
			int[] wh = getSheetWidthAndHeight(sheet);
			int width = wh[0];
			int height = wh[1];

			XSSFDrawing drawingPatriarch = sheet.createDrawingPatriarch();

			//根据宽高进行插入
			for(int i = 0;i< (width / imgW) + 1;i++) {	//x轴
				for(int j = 0; j <( height / imgH) + 1;j++){	//y轴
					int x = i * imgW;
					int y = j * imgH;

					//根据图片插入
					/*XSSFClientAnchor anchor = new XSSFClientAnchor(x,y,x+width,y+height,0,0,1,1);
					int pIndex = xssfworkbook.addPicture(bytes, Workbook.PICTURE_TYPE_PNG);
					drawingPatriarch.createPicture(anchor,pIndex);*/
				}
			}

		}
		if(!outfile.exists()){
			File par = outfile.getParentFile();
			if(!par.exists()){
				par.mkdirs();
			}
			outfile.createNewFile();
		}
		FileOutputStream out = new FileOutputStream(outfile);
		xssfworkbook.write(out);
		out.close();
	}


	/**
	 * 获取sheet的宽高
	 * @param sheet
	 * @return
	 */
	private static int[] getSheetWidthAndHeight(Sheet sheet){
		float height = 0f;
		float width = 0f;
		int firstRowNum = sheet.getFirstRowNum();
		int lastRowNum = sheet.getLastRowNum();
		for (int i = firstRowNum; i < lastRowNum; i++) {
			Row row = sheet.getRow(i);
			if(i == firstRowNum){	//获取宽度
				short firstCellNum = row.getFirstCellNum();
				short lastCellNum = row.getLastCellNum();
				for(int j = firstCellNum;j<lastCellNum;j++){
					width = width + sheet.getColumnWidthInPixels(j);
				}
			}
			height = height+ row.getHeightInPoints();
		}
		return new int[]{Math.round(width),Math.round(height)};
	}


	private static ByteArrayOutputStream createWaterMark(String[] content,int width,int height) throws IOException {
		ClassPathResource resource = new ClassPathResource("font/simsun.ttc");//宋体
		InputStream resourceAsStream = null;
		Font font = null;
		try{
			resourceAsStream = resource.getInputStream();
			font = Font.createFont(Font.TRUETYPE_FONT, resourceAsStream);
			font = font.deriveFont(20f);
		}catch (Exception e){
			throw new IOException("PoiSecurity createWaterMark error",e);
		} finally {
			if(resourceAsStream!=null){
				resourceAsStream.close();
			}
		}
//		(前置知识)
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);// 获取bufferedImage对象
//        设置字体(前置知识)
        Graphics2D g2d = image.createGraphics(); // 获取Graphics2d对象(前置知识)
//		这里实在看不懂,为啥销毁后用BufferedImage重新获取Graphics2d对象
        image = g2d.getDeviceConfiguration().createCompatibleImage(width, height, Transparency.TRANSLUCENT);
        g2d.dispose();
        g2d = image.createGraphics();
        g2d.setColor(new java.awt.Color(0, 0, 0, 40));//设置字体颜色和透明度，最后一个参数为透明度(前置知识)
        g2d.setStroke(new BasicStroke(1)); // 设置字体
        g2d.setFont(font); // 设置字体类型  加粗 大小
        g2d.rotate(-0.5, (double) image.getWidth() / 2, (double) image.getHeight() / 2);//设置倾斜度
//		要想得到表示屏幕设备字体属性的对象(前置知识)
        FontRenderContext context = g2d.getFontRenderContext();
//        循环设置水印文字位置(看不懂)
        for (int i = 0; i < content.length; i++) {
//        	返回包围字符串的矩形(前置知识)
			if(content[i] == null){
				continue;
			}
			Rectangle2D bounds = font.getStringBounds(content[i], context);
//            宽度
            double x = (width - bounds.getWidth()) / 2;
//            高度
            double y = (height - bounds.getHeight()) / 2;
//            上坡度
            double ascent = -bounds.getY();
            double baseY = y + ascent;
            // 写入水印文字原定高度过小，所以累计写水印，增加高度
            g2d.drawString(content[i], (int) x, (int) baseY+(30*i));
		}
        // 设置透明度(前置知识)
//        g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER));
        g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.DST_OVER));
        // 释放对象
        g2d.dispose();
//		ByteArrayOutputStream(前置知识)
        ByteArrayOutputStream os = new ByteArrayOutputStream();
//		BufferedImage –> byte[](前置知识)
		ImageIO.write(image, "png", os);
        return os;
    }


	public static void encXlsx(String paasword,File file) throws InvalidFormatException, IOException, GeneralSecurityException{
		try (POIFSFileSystem fs = new POIFSFileSystem()) {
		    EncryptionInfo info = new EncryptionInfo(EncryptionMode.agile);
		    // EncryptionInfo info = new EncryptionInfo(EncryptionMode.agile, CipherAlgorithm.aes192, HashAlgorithm.sha384, -1, -1, null);
		    Encryptor enc = info.getEncryptor();
		    enc.confirmPassword(paasword);
		    // Read in an existing OOXML file and write to encrypted output stream
		    // don't forget to close the output stream otherwise the padding bytes aren't added
		    try (OPCPackage opc = OPCPackage.open(file, PackageAccess.READ_WRITE);
		        OutputStream os = enc.getDataStream(fs)) {
		        opc.save(os);
		    }
		    // Write out the encrypted version
		    try (FileOutputStream fos = new FileOutputStream(file)) {
		        fs.writeFilesystem(fos);
		    }
		}
	}


}

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