SpringBoot整合poi进行简单的Excel表单导出实现

逃离我推掉我的手 2021-10-09 10:30 322阅读 0赞

**0、先在pom.xml里面添加POI依赖，Java轻熟鸟从第六步看**

<dependency>
                <groupId>org.apache.poi</groupId>
                <artifactId>poi-ooxml</artifactId>
                <version>3.8</version>
            </dependency>

**1、编写mapper.xml文件**

<?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.hotcomm.prevention.db.mysql.datashow.dc.DcMapper">
    
        <select id="selectDeviceList" resultType="import你的查询结果的实体类路径">
            SELECT
            dc.*
            FROM
            t_device_all dc
            INNER JOIN
            t_device_group_relation t1
            ON t1.`deviceid` = dc.`id`
            AND t1.`isdelete`
            = 0
            INNER JOIN t_device_group t2
            ON t1.`groupid` = t2.`id`
            AND
            t2.`isdelete` = 0
            INNER JOIN t_user_dgroup_relation t3
            ON
            t3.`devicegroupid` = t2.`id`
            AND t3.`isdelete` = 0
            INNER JOIN t_user t4
            ON t4.`id` = t3.`userid`
            AND t4.`isdelete` = 0
            AND t4.`id` =#{userid}
        </select>
    </mapper>

**2、写一个存放单表查询结果的实体类（lombok可以自动编译getter和setter,此处省略lombok的配置安装，如需使用请百度）**

import java.io.Serializable;
    import javax.persistence.Column;
    import javax.persistence.GeneratedValue;
    import javax.persistence.GenerationType;
    import javax.persistence.Id;
    import javax.persistence.Table;
    import lombok.Data;
    import lombok.EqualsAndHashCode;
    import lombok.NoArgsConstructor;
    
    @Table(name = "t_device_all ")
    @Data
    @EqualsAndHashCode(callSuper = false)
    @NoArgsConstructor
    public class T_device_all implements Serializable {
    
        private static final long serialVersionUID = 1L;
    
        @Id
        @GeneratedValue(strategy = GenerationType.IDENTITY)
        private Integer id;
    
        @Column(name = "devnum")
        private String devnum;
    
        @Column(name = "mac")
        private String mac;
    
    }

**3、编辑你的毛片儿（mapper.java）**

import java.util.List;
    import org.apache.ibatis.annotations.Param;
    
    public interface DcMapper{
    
        List<T_device_all> selectDeviceList(@Param("userid") Integer userid);
    
    }

**4、编辑service**

import java.text.ParseException;
    import java.util.List;
    
    public interface DcService {
    
        List<T_device_all> selectDevice(Integer userid);
    
    }

**5、接着是serviceImpl（SpringBoot、SSM是真的优雅）**

import java.util.ArrayList;
    import org.springframework.beans.factory.annotation.Autowired;
    
    @Service
    public class DcServiceImpl implements DcService {
    
        @Autowired
        private DcMapper dcMapper;
    
        @Override
        public List<T_device_all> selectDevice(Integer userid) {
            return dcMapper.selectDeviceList(userid);
        }
    
    }

**6、编写Excel模板实体类**

import java.io.Serializable;
    import java.util.List;
    
    import lombok.Data;
    import lombok.EqualsAndHashCode;
    import lombok.NoArgsConstructor;
    
    @Data
    @EqualsAndHashCode(callSuper = false)
    @NoArgsConstructor
    public class ExcelData implements Serializable {
    
        private static final long serialVersionUID = 1L;
    
        // 表头
        private List<String> titles;
    
        // 数据
        private List<List<Object>> rows;
    
        // 页签名称
        private String name;
    
    }

**7、编写Excel工具类（设置你要导出的Excel表格样式，基本不需要修改）**

import javax.servlet.http.HttpServletResponse;
    import java.io.OutputStream;
    import java.util.List;
    
    import org.apache.poi.ss.usermodel.*;
    import org.apache.poi.ss.usermodel.Font;
    import org.apache.poi.xssf.usermodel.XSSFCellStyle;
    import org.apache.poi.xssf.usermodel.XSSFColor;
    import org.apache.poi.xssf.usermodel.XSSFSheet;
    import org.apache.poi.xssf.usermodel.XSSFWorkbook;
    import org.apache.poi.xssf.usermodel.extensions.XSSFCellBorder.BorderSide;
    
    import java.awt.Color;
    import java.net.URLEncoder;
    
    public class ExcelOutPutUtils {
        public static void exportExcel(HttpServletResponse response, String fileName, ExcelData data) throws Exception {
            // 告诉浏览器用什么软件可以打开此文件
            response.setHeader("content-Type", "application/vnd.ms-excel");
            // 下载文件的默认名称
            response.setHeader("Content-Disposition", "attachment;filename="+URLEncoder.encode(fileName, "utf-8"));
            exportExcel(data, response.getOutputStream());
        }
    
        public static void exportExcel(ExcelData data, OutputStream out) throws Exception {
    
            XSSFWorkbook wb = new XSSFWorkbook();
            try {
                String sheetName = data.getName();
                if (null == sheetName) {
                    sheetName = "Sheet1";
                }
                XSSFSheet sheet = wb.createSheet(sheetName);
                writeExcel(wb, sheet, data);
    
                wb.write(out);
            } catch(Exception e){
                e.printStackTrace();
            }finally{
                //此处需要关闭 wb 变量
                out.close();
            }
        }
    
        private static void writeExcel(XSSFWorkbook wb, Sheet sheet, ExcelData data) {
    
            int rowIndex = 0;
    
            rowIndex = writeTitlesToExcel(wb, sheet, data.getTitles());
            writeRowsToExcel(wb, sheet, data.getRows(), rowIndex);
            autoSizeColumns(sheet, data.getTitles().size() + 1);
    
        }
    
        private static int writeTitlesToExcel(XSSFWorkbook wb, Sheet sheet, List<String> titles) {
            int rowIndex = 0;
            int colIndex = 0;
    
            Font titleFont = wb.createFont();
            titleFont.setFontName("simsun");
            //titleFont.setBoldweight(Short.MAX_VALUE);
            // titleFont.setFontHeightInPoints((short) 14);
            titleFont.setColor(IndexedColors.BLACK.index);
    
            XSSFCellStyle titleStyle = wb.createCellStyle();
            titleStyle.setAlignment(XSSFCellStyle.ALIGN_CENTER);
            titleStyle.setVerticalAlignment(XSSFCellStyle.VERTICAL_CENTER);
            titleStyle.setFillForegroundColor(new XSSFColor(new Color(182, 184, 192)));
            titleStyle.setFillPattern(XSSFCellStyle.SOLID_FOREGROUND);
            titleStyle.setFont(titleFont);
            setBorder(titleStyle, BorderStyle.THIN, new XSSFColor(new Color(0, 0, 0)));
    
            Row titleRow = sheet.createRow(rowIndex);
            // titleRow.setHeightInPoints(25);
            colIndex = 0;
    
            for (String field : titles) {
                Cell cell = titleRow.createCell(colIndex);
                cell.setCellValue(field);
                cell.setCellStyle(titleStyle);
                colIndex++;
            }
    
            rowIndex++;
            return rowIndex;
        }
    
        private static int writeRowsToExcel(XSSFWorkbook wb, Sheet sheet, List<List<Object>> rows, int rowIndex) {
            int colIndex = 0;
    
            Font dataFont = wb.createFont();
            dataFont.setFontName("simsun");
            // dataFont.setFontHeightInPoints((short) 14);
            dataFont.setColor(IndexedColors.BLACK.index);
    
            XSSFCellStyle dataStyle = wb.createCellStyle();
            dataStyle.setAlignment(XSSFCellStyle.ALIGN_CENTER);
            dataStyle.setVerticalAlignment(XSSFCellStyle.VERTICAL_CENTER);
            dataStyle.setFont(dataFont);
            setBorder(dataStyle, BorderStyle.THIN, new XSSFColor(new Color(0, 0, 0)));
    
            for (List<Object> rowData : rows) {
                Row dataRow = sheet.createRow(rowIndex);
                // dataRow.setHeightInPoints(25);
                colIndex = 0;
    
                for (Object cellData : rowData) {
                    Cell cell = dataRow.createCell(colIndex);
                    if (cellData != null) {
                        cell.setCellValue(cellData.toString());
                    } else {
                        cell.setCellValue("");
                    }
    
                    cell.setCellStyle(dataStyle);
                    colIndex++;
                }
                rowIndex++;
            }
            return rowIndex;
        }
    
        private static void autoSizeColumns(Sheet sheet, int columnNumber) {
    
            for (int i = 0; i < columnNumber; i++) {
                int orgWidth = sheet.getColumnWidth(i);
                sheet.autoSizeColumn(i, true);
                int newWidth = (int) (sheet.getColumnWidth(i) + 100);
                if (newWidth > orgWidth) {
                    sheet.setColumnWidth(i, newWidth);
                } else {
                    sheet.setColumnWidth(i, orgWidth);
                }
            }
        }
    
        private static void setBorder(XSSFCellStyle style, BorderStyle border, XSSFColor color) {
            style.setBorderTop(border);
            style.setBorderLeft(border);
            style.setBorderRight(border);
            style.setBorderBottom(border);
            style.setBorderColor(BorderSide.TOP, color);
            style.setBorderColor(BorderSide.LEFT, color);
            style.setBorderColor(BorderSide.RIGHT, color);
            style.setBorderColor(BorderSide.BOTTOM, color);
        }
    
    }

**8、配置controller**

import java.text.SimpleDateFormat;
    import java.util.ArrayList;
    import java.util.Date;
    import java.util.List;
    
    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("/excel")
    public class ExcelOutPutController {
    
        @Autowired
        DcService dcService;
    
         @RequestMapping(value = "/export", method = RequestMethod.GET)
            public void excel(HttpServletResponse response) throws Exception {
                ExcelData data = new ExcelData();
                data.setName("hello");
                List<String> titles = new ArrayList();
                titles.add("设备编号");
                titles.add("mac地址");
                data.setTitles(titles);
    
                List<List<Object>> rows = new ArrayList();
                List<T_device_all> list = dcService.selectDevice(1);//sql查询结果放在这个数组里
    
                for (int i = 0; i < list.size(); i++) {//遍历数组，把数组内容放进Excel的行中
                    List<Object> row = new ArrayList();
                    row.add(list.get(i).getDevnum());
                    row.add(list.get(i).getMac());
                    rows.add(i, row);
                }
    
                data.setRows(rows);
    
    
                //生成本地
                /*File f = new File("c:/test.xlsx");
                FileOutputStream out = new FileOutputStream(f);
                ExportExcelUtils.exportExcel(data, out);
                out.close();*/
                SimpleDateFormat fdate=new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss");
                String fileName=fdate.format(new Date())+".xlsx";//老版本的office改成xls
                ExcelOutPutUtils.exportExcel(response,fileName,data);
            }
    }

**最后启动项目，在浏览器中测试**   
![这里写图片描述][70]  
[http://localhost:8081/excel/export?userid=1][http_localhost_8081_excel_export_userid_1]（端口、拦截路基、传参 是自定义的）   
![这里写图片描述][70 1]  
输入地址后敲回车，下载成功了   
![这里写图片描述][70 2]   
结果吻合查询结果，导出完成

[70]: /images/20211009/7a15a029f9764487bc03497b243d46b3.png
[http_localhost_8081_excel_export_userid_1]: http://localhost:8081/excel/export?userid=1
[70 1]: /images/20211009/91c4063352d6402382cf9ed83cbb3337.png
[70 2]: /images/20211009/47622d65d3874e68bd2ba6226361dcde.png