SpringBoot整合EasyExcel

SpringBoot整合EasyExcel

1.导入依赖

添加maven依赖, 依赖的poi最低版本3.17

<dependency>
    <groupId>com.alibabagroupId>
    <artifactId>easyexcelartifactId>
    <version>2.2.3version>
dependency>

2.创建实体类

@NoArgsConstructor
@AllArgsConstructor
@Data
@Builder
public class User {
    @ExcelProperty(value = "用户编号")
    private Integer userId;
    @ExcelProperty(value = "姓名")
    private String userName;
    @ExcelProperty(value = "性别")
    private String gender;
    @ExcelProperty(value = "工资")
    private Double salary;
    @ExcelProperty(value = "入职时间")
    private Date hireDate;
}

3.写入Excel

3.1方法一

根据user模板构建数据

private List<User> getUserData() {
    List<User> users = new ArrayList<>();
    for (int i = 1; i <= 10; i++) {
        User user = User.builder()
                .userId(i)
                .userName("admin" + i)
                .gender(i % 2 == 0 ? "男" : "女")
                .salary(i * 1000.00)
                .hireDate(new Date())
                .build();
        users.add(user);
    }
    return users;
}

@Test
public void testWriteExcel() {

    String filename = "D:\\study\\excel\\user1.xlsx";

    // 向Excel中写入数据 也可以通过 head(Class) 指定数据模板
    EasyExcel.write(filename, User.class)
            .sheet("用户信息")
            .doWrite(getUserData());
}

3.2方法二

@Test
public void testWriteExcel2() {
    String filename = "D:\\study\\excel\\user2.xlsx";
    // 创建ExcelWriter对象
    ExcelWriter excelWriter = EasyExcel.write(filename, User.class).build();
    // 创建Sheet对象
    WriteSheet writeSheet = EasyExcel.writerSheet("用户信息").build();
    // 向Excel中写入数据
    excelWriter.write(getUserData(), writeSheet);
    // 关闭流
    excelWriter.finish();
}

3.3排除模型中某些属性字段

指定字段不写入excel

@Test
public void testWriteExcel3() {
    String filename = "D:\\study\\excel\\user3.xlsx";
    // 设置排除的属性 也可以在数据模型的字段上加@ExcelIgnore注解排除
    Set<String> excludeField = new HashSet<>();
    excludeField.add("hireDate");
    excludeField.add("salary");
    // 写Excel
    EasyExcel.write(filename, User.class)
            .excludeColumnFiledNames(excludeField)
            .sheet("用户信息")
            .doWrite(getUserData());
}

3.4向表格中导出指定属性

@Test
public void testWriteExcel4() {
    String filename = "D:\\study\\excel\\user4.xlsx";
    // 设置要导出的字段
    Set<String> includeFields = new HashSet<>();
    includeFields.add("userName");
    includeFields.add("hireDate");
    // 写Excel
    EasyExcel.write(filename, User.class)
            .includeColumnFiledNames(includeFields)
            .sheet("用户信息")
            .doWrite(getUserData());
}

3.5在Excel表格中进行列排序

只需要在注解ExcelProperty中使用index属性指定列顺序

@NoArgsConstructor
@AllArgsConstructor
@Data
@Builder
public class User {

    @ExcelProperty(value = "用户编号", index = 0)
    private Integer userId;
    @ExcelProperty(value = "姓名", index = 1)
    private String userName;
    @ExcelProperty(value = "性别", index = 3)
    private String gender;
    @ExcelProperty(value = "工资", index = 4)
    private Double salary;
    @ExcelProperty(value = "入职时间", index = 2)
    private Date hireDate;
}

3.6复杂头数据写入

@ExcelProperty注解的value属性是一个数组类型, 设置多个head时会自动合并.

@NoArgsConstructor
@AllArgsConstructor
@Data
@Builder
public class ComplexHeadUser {
    @ExcelProperty(value = {"group1", "用户编号"}, index = 0)
    private Integer userId;
    @ExcelProperty(value = {"group1", "姓名"}, index = 1)
    private String userName;
    @ExcelProperty(value = {"group2", "入职时间"}, index = 2)
    private Date hireDate;
}

3.7写到Excel的不同Sheet中

@Test
public void testWriteExcel8() {
    String filename = "D:\\study\\excel\\user8.xlsx";
    // 创建ExcelWriter对象
    ExcelWriter excelWriter = EasyExcel.write(filename, User.class).build();
    // 向Excel的同一个Sheet重复写入数据
    for (int i = 0; i < 2; i++) {
        // 创建Sheet对象
        WriteSheet writeSheet = EasyExcel.writerSheet("用户信息" + i).build();
        excelWriter.write(getUserData(), writeSheet);
    }
    // 关闭流
    excelWriter.finish();
}

3.8日期/数字类型格式化

对于日期和数字,有时候需要对其展示的样式进行格式化, EasyExcel提供了以下注解

@DateTimeFormat 日期格式化

@NumberFormat 数字格式化(小数或百分数)

@NoArgsConstructor
@AllArgsConstructor
@Data
@Builder
public class User {
    @ExcelProperty(value = "用户编号", index = 0)
    private Integer userId;
    @ExcelProperty(value = "姓名", index = 1)
    private String userName;
    @ExcelProperty(value = "性别", index = 3)
    private String gender;
    @ExcelProperty(value = "工资", index = 4)
    @NumberFormat(value = "###.#") // 数字格式化,保留1位小数
    private Double salary;
    @ExcelProperty(value = "入职时间", index = 2)
    @DateTimeFormat(value = "yyyy年MM月dd日 HH时mm分ss秒") // 日期格式化
    private Date hireDate;
}

3.9写入图片到Excel

@NoArgsConstructor
@AllArgsConstructor
@Data
@Builder
@ContentRowHeight(value = 100) // 内容行高
@ColumnWidth(value = 20) // 列宽
public class ImageData {

    //使用抽象文件表示一个图片
    @ExcelProperty(value = "File类型")
    private File file;
    // 使用输入流保存一个图片
    @ExcelProperty(value = "InputStream类型")
    private InputStream inputStream;
    // 当使用String类型保存一个图片的时候需要使用StringImageConverter转换器
    @ExcelProperty(value = "String类型", converter = StringImageConverter.class)
    private String str;
    // 使用二进制数据保存为一个图片
    @ExcelProperty(value = "二进制数据(字节)")
    private byte[] byteArr;
    // 使用网络链接保存为一个图片
    @ExcelProperty(value = "网络图片")
    private URL url;
}

@Test
public void testWriteImageToExcel() throws IOException {
    String filename = "D:\\study\\excel\\user10.xlsx";
    // 图片位置
    String imagePath = "D:\\study\\excel\\me.jpg";
    // 网络图片
    URL url = new URL("https://cn.bing.com/th?id=OHR.TanzaniaBeeEater_ZH-CN3246625733_1920x1080.jpg&rf=LaDigue_1920x1080.jpg&pid=hp");
   // 将图片读取到二进制数据中
    byte[] bytes = new byte[(int) new File(imagePath).length()];
    InputStream inputStream = new FileInputStream(imagePath);
    inputStream.read(bytes, 0, bytes.length);

    List<ImageData> imageDataList = new ArrayList<>();

    // 创建数据模板
    ImageData imageData = ImageData.builder()
            .file(new File(imagePath))
            .inputStream(new FileInputStream(imagePath))
            .str(imagePath)
            .byteArr(bytes)
            .url(url)
            .build();
    // 添加要写入的图片模型
    imageDataList.add(imageData);

    // 写数据
    EasyExcel.write(filename, ImageData.class)
            .sheet("帅哥")
            .doWrite(imageDataList);
}

3.10设置写入Excel的列宽和行高

@HeadRowHeight(value = 30) // 头部行高
@ContentRowHeight(value = 25) // 内容行高
@ColumnWidth(value = 20) // 列宽, 可以作用在类或字段上

@NoArgsConstructor
@AllArgsConstructor
@Data
@Builder
@HeadRowHeight(value = 30) // 头部行高
@ContentRowHeight(value = 25) // 内容行高
@ColumnWidth(value = 20) // 列宽
public class WidthAndHeightData {
    @ExcelProperty(value = "字符串标题")
    private String string;
    @ExcelProperty(value = "日期标题")
    private Date date;
    @ExcelProperty(value = "数字标题")
    @ColumnWidth(value = 25)
    private Double doubleData;
}

3.11通过注解形式设置写入Excel样式

@NoArgsConstructor
@AllArgsConstructor
@Data
@Builder
@HeadRowHeight(value = 30) // 头部行高
@ContentRowHeight(value = 25) // 内容行高
@ColumnWidth(value = 20) // 列宽
// 头背景设置成红色 IndexedColors.RED.getIndex()
@HeadStyle(fillPatternType = FillPatternType.SOLID_FOREGROUND, fillForegroundColor = 10)
// 头字体设置成20, 字体默认宋体
@HeadFontStyle(fontName = "宋体", fontHeightInPoints = 20)
// 内容的背景设置成绿色  IndexedColors.GREEN.getIndex()
@ContentStyle(fillPatternType = FillPatternType.SOLID_FOREGROUND, fillForegroundColor = 17)
// 内容字体设置成20, 字体默认宋体
@ContentFontStyle(fontName = "宋体", fontHeightInPoints = 20)
public class DemoStyleData {

    // 字符串的头背景设置成粉红 IndexedColors.PINK.getIndex()
    @HeadStyle(fillPatternType = FillPatternType.SOLID_FOREGROUND, fillForegroundColor = 14)
    // 字符串的头字体设置成20
    @HeadFontStyle(fontHeightInPoints = 30)
    // 字符串的内容背景设置成天蓝 IndexedColors.SKY_BLUE.getIndex()
    @ContentStyle(fillPatternType = FillPatternType.SOLID_FOREGROUND, fillForegroundColor = 40)
    // 字符串的内容字体设置成20,默认宋体
    @ContentFontStyle(fontName = "宋体", fontHeightInPoints = 20)
    @ExcelProperty(value = "字符串标题")
    private String string;
    @ExcelProperty(value = "日期标题")
    private Date date;
    @ExcelProperty(value = "数字标题")
    private Double doubleData;
}

3.12合并单元格

@OnceAbsoluteMerge 指定从哪一行/列开始,哪一行/列结束,进行单元格合并

• firstRowIndex 起始行索引,从0开始
• lastRowIndex 结束行索引
• firstColumnIndex 起始列索引,从0开始
• lastColumnIndex 结束列索引

@NoArgsConstructor
@AllArgsConstructor
@Data
@Builder
@HeadRowHeight(value = 25) // 头部行高
@ContentRowHeight(value = 20) // 内容行高
@ColumnWidth(value = 20) // 列宽
// 例如: 第2-3行,2-3列进行合并
@OnceAbsoluteMerge(firstRowIndex = 1, lastRowIndex = 2, firstColumnIndex = 1, lastColumnIndex = 2)
public class DemoMergeData {

    // 每隔两行合并一次(竖着合并单元格)
//    @ContentLoopMerge(eachRow = 2)
    @ExcelProperty(value = "字符串标题")
    private String string;
    @ExcelProperty(value = "日期标题")
    private Date date;
    @ExcelProperty(value = "数字标题")
    private Double doubleData;
}

3.13数据转换器

在实际应用场景中, 我们系统db存储的数据可以是枚举, 在界面或导出到Excel文件需要展示为对于的枚举值形式.

比如: 性别, 状态等. EasyExcel提供了转换器接口Converter供我们使用, 我们只需要自定义转换器实现接口, 并将自定义转换器类型传入要转换的属性字段中. 以下面的性别gender字段为例:

@NoArgsConstructor
@AllArgsConstructor
@Data
@Builder
public class UserModel {

    @ExcelProperty(value = "用户编号", index = 0)
    private Integer userId;
    @ExcelProperty(value = "姓名", index = 1)
    private String userName;
   // 性别添加了转换器, db中存入的是integer类型的枚举 0 , 1 ,2
    @ExcelProperty(value = "性别", index = 3, converter = GenderConverter.class)
    private Integer gender;
    @ExcelProperty(value = "工资", index = 4)
    @NumberFormat(value = "###.#")
    private Double salary;
    @ExcelProperty(value = "入职时间", index = 2)
    @DateTimeFormat(value = "yyyy年MM月dd日 HH时mm分ss秒")
    private Date hireDate;
}

/**
 * 类描述：性别字段的数据转换器
 * @Author wang_qz
 * @Date 2021/8/15 19:16
 * @Version 1.0
 */
public class GenderConverter implements Converter<Integer> {

    private static final String MALE = "男";
    private static final String FEMALE = "女";
    private static final String NONE = "未知";

    // Java数据类型 integer
    @Override
    public Class supportJavaTypeKey() {
        return Integer.class;
    }

    // Excel文件中单元格的数据类型  string
    @Override
    public CellDataTypeEnum supportExcelTypeKey() {
        return CellDataTypeEnum.STRING;
    }

    // 读取Excel文件时将string转换为integer
    @Override
    public Integer convertToJavaData(CellData cellData, ExcelContentProperty contentProperty, GlobalConfiguration globalConfiguration) 
       throws Exception {
        String value = cellData.getStringValue();
        if (Objects.equals(FEMALE, value)) {
            return 0; // 0-女
        } else if (Objects.equals(MALE, value)) {
            return 1; // 1-男
        }
        return 2; // 2-未知
    }

    // 写入Excel文件时将integer转换为string
    @Override
    public CellData convertToExcelData(Integer value, ExcelContentProperty contentProperty, GlobalConfiguration globalConfiguration) throws Exception {
        if (value == 1) {
            return new CellData(MALE);
        } else if (value == 0) {
            return new CellData(FEMALE);
        }
        return new CellData(NONE); // 不男不女
    }
}

4.读Excel

4.1读API的拆分

在读取Excel表格数据时, 将读取的每行记录映射成一条LinkedHashMap记录, 而没有映射成实体类.

@Test
public void testRead() {
    String filename = "D:\\study\\excel\\read.xlsx";
    // 创建ExcelReaderBuilder对象
    ExcelReaderBuilder readerBuilder = EasyExcel.read();
    // 获取文件对象
    readerBuilder.file(filename);
   // 指定映射的数据模板
//  readerBuilder.head(DemoData.class);
    // 指定sheet
    readerBuilder.sheet(0);
    // 自动关闭输入流
    readerBuilder.autoCloseStream(true);
    // 设置Excel文件格式
    readerBuilder.excelType(ExcelTypeEnum.XLSX);
    // 注册监听器进行数据的解析
    readerBuilder.registerReadListener(new AnalysisEventListener() {
        // 每解析一行数据,该方法会被调用一次
        @Override
        public void invoke(Object demoData, AnalysisContext analysisContext) {
            // 如果没有指定数据模板, 解析的数据会封装成 LinkedHashMap返回
            // demoData instanceof LinkedHashMap 返回 true
            System.out.println("解析数据为:" + demoData.toString());
        }

        // 全部解析完成被调用
        @Override
        public void doAfterAllAnalysed(AnalysisContext analysisContext) {
            System.out.println("解析完成...");
            // 可以将解析的数据保存到数据库
        }
    });
    readerBuilder.doReadAll();
  /*  // 构建读取器
    ExcelReader excelReader = readerBuilder.build();
    // 读取Excel
    excelReader.readAll();
    // 关闭流
    excelReader.finish();*/

}

4.2方法一

关键是写一个监听器,实现AnalysisEventListener, 每解析一行数据会调用invoke方法返回解析的数据, 当全部解析完成后会调用doAfterAllAnalysed方法. 我们重写invoke方法和doAfterAllAnalysed方法即可.

@Test
public void testReadExcel() {
    // 读取的excel文件路径
    String filename = "D:\\study\\excel\\read.xlsx";
    // 读取excel
    EasyExcel.read(filename, DemoData.class, new AnalysisEventListener<DemoData>() {
        // 每解析一行数据,该方法会被调用一次
        @Override
        public void invoke(DemoData demoData, AnalysisContext analysisContext) {
            System.out.println("解析数据为:" + demoData.toString());
        }
        // 全部解析完成被调用
        @Override
        public void doAfterAllAnalysed(AnalysisContext analysisContext) {
            System.out.println("解析完成...");
            // 可以将解析的数据保存到数据库
        }
    }).sheet().doRead();
}

4.3方法二

@Test
public void testReadExcel2() {
    // 读取的excel文件路径
    String filename = "D:\\study\\excel\\read.xlsx";
    // 创建一个数据格式来装读取到的数据
    Class<DemoData> head = DemoData.class;
    // 创建ExcelReader对象
    ExcelReader excelReader = EasyExcel.read(filename, head, new AnalysisEventListener<DemoData>() {
        // 每解析一行数据,该方法会被调用一次
        @Override
        public void invoke(DemoData demoData, AnalysisContext analysisContext) {
            System.out.println("解析数据为:" + demoData.toString());
        }
        // 全部解析完成被调用
        @Override
        public void doAfterAllAnalysed(AnalysisContext analysisContext) {
            System.out.println("解析完成...");
            // 可以将解析的数据保存到数据库
        }
    }).build();
    // 创建sheet对象,并读取Excel的第一个sheet(下标从0开始), 也可以根据sheet名称获取
    ReadSheet sheet = EasyExcel.readSheet(0).build();
    // 读取sheet表格数据, 参数是可变参数,可以读取多个sheet
    excelReader.read(sheet);
    // 需要自己关闭流操作,在读取文件时会创建临时文件,如果不关闭,会损耗磁盘,严重的磁盘爆掉
    excelReader.finish();
}

5.Excel下载

5.1方法一

**
 * 使用EasyExcel操作excel文件上传/下载
 */
@Controller
@RequestMapping(value = "/xlsx")
public class EasyExcelController {

    @RequestMapping("/toExcelPage")
    public String todownloadPage() {
        return "excelPage";
    }

    /**
     * 下载Excel
     * @param request
     * @param response
     */
    @RequestMapping(value = "/downloadExcel")
    public void downloadExcel(HttpServletRequest request, 
                              HttpServletResponse response) throws Exception {
        // 设置响应头
        response.setContentType("application/vnd.ms-excel");
        response.setCharacterEncoding("utf-8");
        // 设置防止中文名乱码
        String filename = URLEncoder.encode("员工信息", "utf-8");
        // 文件下载方式(附件下载还是在当前浏览器打开)
        response.setHeader("Content-disposition", "attachment;filename=" + 
                           filename + ".xlsx");
        // 构建写入到excel文件的数据
        List<UserExcel> userExcels = new ArrayList<>();
        UserExcel userExce1 = new UserExcel(1001, "张三", "男", 1333.33, 
                                            new Date());
        UserExcel userExce2 = new UserExcel(1002, "李四", "男", 1356.83, 
                                            new Date());
        UserExcel userExce3 = new UserExcel(1003, "王五", "男", 1883.66, 
                                            new Date());
        UserExcel userExce4 = new UserExcel(1004, "赵六", "男", 1393.39, 
                                            new Date());
        userExcels.add(userExce1);
        userExcels.add(userExce2);
        userExcels.add(userExce3);
        userExcels.add(userExce4);
        // 写入数据到excel
        EasyExcel.write(response.getOutputStream(), UserExcel.class)
                .sheet("用户信息")
                .doWrite(userExcels);
    }
}

5.2方法二

**
 * 使用EasyExcel操作excel文件上传/下载
 */
@Controller
@RequestMapping(value = "/xlsx")
public class EasyExcelController {

    /**
     * 下载Excel
     * @param request
     * @param response
     */
    @RequestMapping(value = "/downloadExcel")
    public void downloadExcel(HttpServletRequest request, 
      String fileName = "user2.xlsx"；
       String path = "D:\\study\\excel\\"+fileName;
    // 创建ExcelWriter对象
    ExcelWriter excelWriter = EasyExcel.write(path, User.class).build();
    // 创建Sheet对象
    WriteSheet writeSheet = EasyExcel.writerSheet("用户信息").build();
    // 向Excel中写入数据
    excelWriter.write(getUserData(), writeSheet);
    // 关闭流
    excelWriter.finish();
                             
    File file = new File(path);//创建出要下载的文件
    String downname = new String(fileName.getBytes("UTF-8"), "ISO-8859-1");
    resp.setHeader("content-disposition", "attachment;filename=" + downname);//filename=下载文件的名字 只认iso-8859-1
    FileInputStream inputStream = new FileInputStream(file);//读取文件
    OutputStream outputStream = resp.getOutputStream();//写到客户端
    byte[] bs = new byte[(int) file.length()];
    inputStream.read(bs);
    outputStream.write(bs);
    outputStream.close();
    inputStream.close();
    }
}

前端页面

            <a th:href="@{/xlsx/downloadExcel}" style="color: white;text-decoration: none;">导出Excela>

6.Excl上传

 @PostMapping("/upload")
    public R<List> fileUpload(MultipartFile file) {
        //获取文件名
        String originalFilename = file.getOriginalFilename();
        //获取文件后缀名
        String substring = originalFilename.substring(originalFilename.lastIndexOf("."));
        //用UUID随机生成文件名，防止文件名重复导入文件覆盖
        String filename = UUID.randomUUID().toString() + substring;
        //判断当前文件是否存在
        File file1 = new File(filePath);
        if (!file1.exists()) {
            // 不存在，需要创建
            file1.mkdir();
        }
        //保存文件到指定位置
        try {
            file.transferTo(new File(filePath + filename));
        } catch (IOException e) {
            e.printStackTrace();
        }
        List list = planCourseByExcel(filePath + filename);
        return R.success(list);
    }

前端页面

doctype html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>Titletitle>
head>
<body>
<form th:action="@{/admin/upload}" method="POST" enctype="multipart/form-data">
    <input type="file" id="folder" name="file" accept=".xls,.xlsx"/>
    <input type="submit" value="上传文件夹"/>
form>
body>
html>