springboot中使用poi导出excel文件

1.POI简介

　　Jakarta POI 是一套用于访问微软格式文档的Java API.
　　组件HWPF用于操作Word的;
　　组件HSSF用于操作Excel格式文件.

2.常用组件
　　HSSFWorkbook -- excel的文档对象
　　HSSFSheet -- excel的表单
　　HSSFRow -- excel的行
　　HSSFCell -- excel的格子单元
　　HSSFHeader -- sheet头
　　HSSFFooter -- sheet尾（只有打印的时候才能看到效果）
　　HSSFDataFormat -- 日期格式
　　HSSFCellStyle -- cell样式
　　HSSFFont -- excel字体
　　HSSFColor -- 颜色
　　HSSFDateUtil -- 日期
　　HSSFPrintSetup -- 打印
　　HSSFErrorConstants -- 错误信息表

　　合并单元格,构造参数依次表示起始行,截止行,起始列,截止列
　　　　eg:sheet.addMergedRegion(new CellRangeAddress(0,0,0,3));

　　设置单元格样式时,先创建样式,再指定到单元格。
　　　　样式可指定对齐方式、背景填充方式及颜色、上下左右边框样式及颜色

　　设置单元格的填充方式，以及前景颜色和背景颜色时注意：
　　　　a.如果需要前景颜色或背景颜色，一定要指定填充方式，两者顺序无所谓；
　　　　b.如果同时存在前景颜色和背景颜色，前景颜色的设置要写在前面；
　　　　c.前景颜色不是字体颜色。

3.结构说明
　　Excel <-- 一 工作空间(workbook)
　　workbook <-- 多 工作表(sheet)
　　sheet <-- 多 行(row) + 多列(cell)

4.操作步骤
　　a、用HSSFWorkbook打开或者创建Excel文件对象
　　b、用HSSFWorkbook对象返回或者创建Sheet对象
　　c、用Sheet对象返回行对象，用行对象得到Cell对象
　　d、对Cell对象读写

5.实例
　　第一种方法 固定导出字段导出excel;
　　第二种方法 用配置的方式将导出字段存储数库中导出excel,可重用;

　　pom.xml

　　　　　<!-- json转换工具 -->
        <dependency>
            <groupId>net.sf.json-lib</groupId>
            <artifactId>json-lib</artifactId>
            <version>2.4</version>
            <classifier>jdk15</classifier>
        </dependency>
        
        <!-- easypoi 导入导出插件-->
        <dependency>
            <groupId>cn.afterturn</groupId>
            <artifactId>easypoi-base</artifactId>
            <version>3.0.3</version>
        </dependency>
        <dependency>
            <groupId>cn.afterturn</groupId>
            <artifactId>easypoi-web</artifactId>
            <version>3.0.3</version>
        </dependency>
        <dependency>
            <groupId>cn.afterturn</groupId>
            <artifactId>easypoi-annotation</artifactId>
            <version>3.0.3</version>
        </dependency>
        
        <!-- POI，excel导入需要的 -->    
        <dependency>
          <groupId>org.apache.poi</groupId>
          <artifactId>poi-ooxml</artifactId>
          <version>3.9</version>
        </dependency>
        <dependency>
          <groupId>commons-fileupload</groupId>
          <artifactId>commons-fileupload</artifactId>
          <version>1.3.1</version>
        </dependency>
        <dependency>
          <groupId>commons-io</groupId>
          <artifactId>commons-io</artifactId>
          <version>2.4</version>
        </dependency>

　　IExportExcleService.java   接口

package com.wulss.jakartapoi.hssf;

import java.util.List;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public interface IExportExcelService {

    /**
     * 第一种 直接导出excle
     * @param req
     * @param resp
     * @param list 要导出的数据
     */
    public void exportExcelWithSimple(HttpServletRequest req,HttpServletResponse resp,List<UserConsumeDetailRecord> list);
    
    /**
     * 第二种 根据exportKey查询出要导出的字段,并匹配list每个类中字段来导出excel,只需维护数据库,即可实现该方法的重用
     * @param exportKey 数据库中存储的导出英文名
     * @param fileName 文件名
     * @param list 要导出的数据
     * @param req
     * @param resp
     */
    public void exportExcelWithDispose(String exportKey,String fileName,List<?> list,HttpServletRequest req,HttpServletResponse resp);
}

　　ExportExcleServiceImpl.java  实现类

package com.wulss.jakartapoi.hssf;

import java.text.SimpleDateFormat;
import java.util.List;
import java.util.UUID;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

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.util.CellRangeAddress;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

@Service
public class ExportExcelServiceImpl extends ExportExcelBaseService implements IExportExcelService{

    @Autowired
    private ExportMapper exportMapper;
    
    @Override
    public void exportExcelWithSimple(HttpServletRequest req,HttpServletResponse resp,List<UserConsumeDetailRecord> list){
        String fileName = "个人消费明细表" + UUID.randomUUID().toString();
        try {    
            //工作空间
            HSSFWorkbook workbook = new HSSFWorkbook();
            
            //第1张工作表
            HSSFSheet sheet1 = workbook.createSheet("个人消费明细"); 
            sheet1.setDefaultRowHeightInPoints(20);//行高
            sheet1.setDefaultColumnWidth(20);//列宽
            
            //行标题
            HSSFRow titleRow = sheet1.createRow(0);
            titleRow.createCell(0).setCellValue("个人消费明细表");
            sheet1.addMergedRegion(new CellRangeAddress(0,0,0,4));////合并单元格
    
            //行表头
            HSSFRow headRow = sheet1.createRow(sheet1.getLastRowNum() + 1);
            headRow.createCell(0).setCellValue("序号");
            headRow.createCell(headRow.getLastCellNum()).setCellValue("用户姓名");
            headRow.createCell(headRow.getLastCellNum()).setCellValue("消费金额");
            headRow.createCell(headRow.getLastCellNum()).setCellValue("消费时间");
            headRow.createCell(headRow.getLastCellNum()).setCellValue("消费项目");
    
            //行表头单元格设置样式
            for(int h = 0; h < headRow.getLastCellNum() ; h ++) {
                headRow.getCell(h).setCellStyle(super.getCellStyle(workbook));
            }
            
            //行数据体
            int index = 1;
            HSSFRow bodyRow = null;
            
            for(UserConsumeDetailRecord bean:list) {
                bodyRow = sheet1.createRow(sheet1.getLastRowNum() + 1);
                
                bodyRow.createCell(0).setCellValue(index ++ );
                bodyRow.createCell(bodyRow.getLastCellNum()).setCellValue(bean.getUserName());
                bodyRow.createCell(bodyRow.getLastCellNum()).setCellValue(bean.getConsumeAmount());
                bodyRow.createCell(bodyRow.getLastCellNum()).setCellValue(
                        new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(bean.getConsumeDate()));//.split("\.")[0]
                bodyRow.createCell(bodyRow.getLastCellNum()).setCellValue(bean.getConsumeTitle());
                
            }

            //输出
            super.outExcelStream(resp, workbook, fileName);
            
            //将生成的excel文件写到磁盘
//            FileOutputStream fos = new FileOutputStream(fileName + ".xls");
//            workbook.write(fos);
//            fos.close();
            //从磁盘删除删除文件
//            super.deleteFileDir(fileName + ".xls");
            
        }catch(Exception e){
            e.printStackTrace();
        }
    }
    
    @Override
    public void exportExcelWithDispose(String exportKey,String fileName,List<?> list,HttpServletRequest req,HttpServletResponse resp){
        //查询一表 级联 获取多表集合
        List<ExportFieldBean> fieldBeanList = exportMapper.getExportByExportKey(exportKey).getFieldBeanList();
        
        try {    
            //工作空间
            HSSFWorkbook workbook = new HSSFWorkbook();
            
            //第1张工作表
            HSSFSheet sheet1 = workbook.createSheet("个人消费明细"); 
            sheet1.setDefaultRowHeightInPoints(20);//行高
            sheet1.setDefaultColumnWidth(20);//列宽
    
            //行表头
            HSSFRow headRow = sheet1.createRow(0);
            headRow.createCell(0).setCellValue("序号");
            headRow.getCell(0).setCellStyle(super.getCellStyle(workbook));
            
            //创建行表头单元格并设置样式
            for(ExportFieldBean fieldBean:fieldBeanList) {
                headRow.createCell(headRow.getLastCellNum()).setCellValue(fieldBean.getExportName());//赋值
                headRow.getCell(headRow.getLastCellNum()).setCellStyle(super.getCellStyle(workbook));//样式
            }
            
            //创建行数据体
            int index = 1;
            HSSFRow bodyRow = null;
            JSONArray jsonArray = JSONArray.fromObject(list);// --赋值(先转json, 再赋值, 通用性高)
            
            for(Object obj:jsonArray) {
                
                bodyRow = sheet1.createRow(sheet1.getLastRowNum() + 1);
                
                bodyRow.createCell(0).setCellValue(index ++ );
                
                for(ExportFieldBean fieldBean:fieldBeanList) {
                    bodyRow.createCell(bodyRow.getLastCellNum()).setCellValue(((JSONObject)obj).get(fieldBean.getExportCode()) + "");//赋值
//                    bodyRow.getCell(bodyRow.getLastCellNum()).setCellStyle(super.getCellStyle(workbook));//样式
                }
            }

            //输出
            super.outExcelStream(resp, workbook, fileName);
            
        }catch(Exception e){
            e.printStackTrace();
        }
    }

}

　　ExportExcelBaseService.java 基础类

package com.wulss.jakartapoi.hssf;

import java.io.File;
import java.io.IOException;
import java.io.OutputStream;

import javax.servlet.http.HttpServletResponse;

import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFDataFormat;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.ss.usermodel.Workbook;
import org.springframework.stereotype.Component;

@Component
public class ExportExcelBaseService {
    /**
     * 获取设置好的样式
     * @param workbook 工作空间
     * @return
     */
    public HSSFCellStyle getCellStyle(HSSFWorkbook workbook) {
        HSSFCellStyle cellStyle = workbook.createCellStyle();
        cellStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);//单元格-垂直居中
        cellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);//单元格-水平居中
        
        cellStyle.setFillPattern(HSSFCellStyle.DIAMONDS);//背景色-方块填充
        cellStyle.setFillForegroundColor(HSSFColor.SKY_BLUE.index);//前背景色-天蓝
        cellStyle.setFillBackgroundColor(HSSFColor.LIGHT_YELLOW.index);//后背景色-浅黄
        

        cellStyle.setBorderBottom(HSSFCellStyle.BORDER_SLANTED_DASH_DOT);//底边框样式-倾斜断点          
        cellStyle.setBottomBorderColor(HSSFColor.DARK_RED.index);//底边框颜色-暗红
        
        cellStyle.setDataFormat(HSSFDataFormat.getBuiltinFormat("m/d/yy h:mm"));//日期显示格式
//        headRowCellStyle.setDataFormat(HSSFDataFormat.getBuiltinFormat("@"));
        
        cellStyle.setFont(this.getFont(workbook));//设置字体
        
        return cellStyle;
    }
    
    /**
     * 获取设置好的字体
     * @param workbook 工作空间
     * @return
     */
    public HSSFFont getFont(HSSFWorkbook workbook) {
        HSSFFont fontStyle = workbook.createFont(); 
        fontStyle.setFontName("宋体");//名称-宋体
        fontStyle.setFontHeightInPoints((short)13);//高度-13
        fontStyle.setColor(HSSFColor.WHITE.index);//颜色-白色
        fontStyle.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);//加粗
        fontStyle.setItalic(true);//斜体
        fontStyle.setUnderline(HSSFFont.U_SINGLE);//下划线
        
        return fontStyle;
    }
    
    /**
     * 通过流的方式输出excle到页面
     * @param response 响应
     * @param workbook 工作空间
     * @param fileName 文件名
     */
    public void outExcelStream(HttpServletResponse response, Workbook workbook, String fileName){
        OutputStream os = null;
        try {
            os = response.getOutputStream();
            response.setContentType("application/x-download");
            response.setCharacterEncoding("UTF-8");
            response.setHeader("Content-disposition", "attachment;filename=" + new String(fileName.getBytes(), "ISO8859-1") + ".xls");
            workbook.write(os);
            os.flush();
        }catch (Exception e) {
            e.printStackTrace();
        }finally {
            if(os!=null){
                try {
                    os.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
    
    //删除单个文件夹
    public void deleteFileDir(String fileName) {  
        File file = new File(fileName);  
        DeleteAll(file);
    }
    

    public void DeleteAll(File dir) {
        if (dir.isFile()) {
            dir.delete();
            return;
 
        } else {
            File[] files = dir.listFiles();
            for (File file : files) {
 
                DeleteAll(file);
            }
        }
 
        dir.delete();
    }
}

　　ExportExcelController.java

package com.wulss.jakartapoi.hssf;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.UUID;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/exportExlce")
public class ExportExcelController {

    @Autowired
    IExportExcelService iExportExcelService;
    
    @RequestMapping(value="/withSimple",method=RequestMethod.GET)
    public String withSimple(HttpServletRequest req,HttpServletResponse resp) {
        List<UserConsumeDetailRecord> list = new ArrayList<>();
        
        UserConsumeDetailRecord record = null;
        for(int i=0;i<10;i++) {
            record = new UserConsumeDetailRecord();
            
            record.setUserName("奥雷里亚诺");
            record.setConsumeAmount(6.66);
            record.setConsumeDate(new Date());
            record.setConsumeTitle("喝酒吃肉");
            
            list.add(record);
        }
        
        iExportExcelService.exportExcelWithSimple(req, resp, list);
        
        return "success";
    }
    
    @RequestMapping(value="/withDispose",method=RequestMethod.GET)
    public String WithDispose(HttpServletRequest req,HttpServletResponse resp) {
        List<UserConsumeDetailRecord> list = new ArrayList<>();
        
        UserConsumeDetailRecord record = null;
        for(int i=0;i<10;i++) {
            record = new UserConsumeDetailRecord();
            
            record.setUserName("奥雷里亚诺");
            record.setConsumeAmount(6.66);
            record.setConsumeDate(new Date());
            record.setConsumeTitle("喝酒吃肉");
            
            list.add(record);
        }
        
        iExportExcelService.exportExcelWithDispose("consume_detail", "个人消费明细表" + UUID.randomUUID().toString(), list, req, resp);
        
        return "success";
    }
}

　　第二种方法涉及到的建表语句

CREATE TABLE `export` (
  `id` int(32) unsigned NOT NULL AUTO_INCREMENT COMMENT '主键',
  `export_code` varchar(255) DEFAULT NULL COMMENT '导出主题英文名',
  `export_name` varchar(255) DEFAULT NULL COMMENT '导出主题中文名'
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 COMMENT='导出主题表';

CREATE TABLE `export_field` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT COMMENT '主键',
  `export_id` int(11) unsigned DEFAULT NULL COMMENT '导出主表ID',
  `field_code` varchar(55) DEFAULT NULL COMMENT '字段英文名',
  `field_name` varchar(64) DEFAULT NULL COMMENT '字段中文名',
  `sort` int(11) unsigned DEFAULT '1' COMMENT '排序字段'
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 COMMENT='导出字段表';

　数据截图

　　表一

　　表二

　　涉及到的 UserConsumeDetailRecord.java 、ExportBean.java、ExportFieldBean.java、ExportMapper.java等，mybatis映射文件就不贴出来了

/**
 * 
 * @Descript TODO (用户消费实体)
 * @author Administrator
 * @date 2019年5月24日
 *
 */
public class UserConsumeDetailRecord {
    private int id;
    
    private int userId;
    
    private String userName;
    
    private String userTel;
    
    private String consumeTitle;
    
    private Date consumeDate;
    
    private Double consumeAmount;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public int getUserId() {
        return userId;
    }

    public void setUserId(int userId) {
        this.userId = userId;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getUserTel() {
        return userTel;
    }

    public void setUserTel(String userTel) {
        this.userTel = userTel;
    }

    public String getConsumeTitle() {
        return consumeTitle;
    }

    public void setConsumeTitle(String consumeTitle) {
        this.consumeTitle = consumeTitle;
    }

    public Date getConsumeDate() {
        return consumeDate;
    }

    public void setConsumeDate(Date consumeDate) {
        this.consumeDate = consumeDate;
    }

    public Double getConsumeAmount() {
        return consumeAmount;
    }

    public void setConsumeAmount(Double consumeAmount) {
        this.consumeAmount = consumeAmount;
    }
}

/**
 * 
 * @Descript TODO (导出主题表)
 * @author Administrator
 * @date 2019年5月27日
 *
 */
public class ExportBean {

    private Integer id;
    
    private String exportCode;
    
    private String exportName;
    
    private List<ExportFieldBean> fieldBeanList;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getExportCode() {
        return exportCode;
    }

    public void setExportCode(String exportCode) {
        this.exportCode = exportCode;
    }

    public String getExportName() {
        return exportName;
    }

    public void setExportName(String exportName) {
        this.exportName = exportName;
    }

    public List<ExportFieldBean> getFieldBeanList() {
        return fieldBeanList;
    }

    public void setFieldBeanList(List<ExportFieldBean> fieldBeanList) {
        this.fieldBeanList = fieldBeanList;
    }
}

/**
 * 
 * @Descript TODO (导出字段表)
 * @author Administrator
 * @date 2019年5月27日
 *
 */
public class ExportFieldBean {
    private Integer id;
    
    private Integer exportId;
    
    private String exportCode;
    
    private String exportName;

    private Integer sort;
    
    private ExportBean exportBean;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public Integer getExportId() {
        return exportId;
    }

    public void setExportId(Integer exportId) {
        this.exportId = exportId;
    }

    public String getExportCode() {
        return exportCode;
    }

    public void setExportCode(String exportCode) {
        this.exportCode = exportCode;
    }

    public String getExportName() {
        return exportName;
    }

    public void setExportName(String exportName) {
        this.exportName = exportName;
    }

    public Integer getSort() {
        return sort;
    }

    public void setSort(Integer sort) {
        this.sort = sort;
    }

    public ExportBean getExportBean() {
        return exportBean;
    }

    public void setExportBean(ExportBean exportBean) {
        this.exportBean = exportBean;
    }
}

@Mapper
public interface ExportMapper {

    ExportBean getExportByExportKey(String exportKey);
}

　　其他更详细的可以参考此文章https://www.cnblogs.com/dawnheaven/p/4462572.html