• SpringBoot导入导出Excel到Mysql


    2018.11.11 10:44:52字数 96阅读 1320

    一、包的引用

    除了引用SpringBoot基本包之外,还需要引入对Excel操作的包,如下:
    
    <dependency>
                <groupId>org.apache.poi</groupId>
                <artifactId>poi</artifactId>
                <version>3.17</version>
            </dependency>
            <!-- https://mvnrepository.com/artifact/org.apache.poi/poi-ooxml
             此版本需高于3.17,等于也行吧-->
            <dependency>
                <groupId>org.apache.poi</groupId>
                <artifactId>poi-ooxml</artifactId>
                <version>3.17</version>
            </dependency>
    

    二、Excel工具包及实体所需bean定义

    1. 工具类
    import org.apache.commons.collections.CollectionUtils;
    import org.apache.commons.lang3.BooleanUtils;
    import org.apache.commons.lang3.CharUtils;
    import org.apache.commons.lang3.StringUtils;
    import org.apache.commons.lang3.math.NumberUtils;
    import org.apache.poi.hssf.usermodel.HSSFDateUtil;
    import org.apache.poi.hssf.usermodel.HSSFWorkbook;
    import org.apache.poi.ss.usermodel.*;
    import org.apache.poi.xssf.usermodel.XSSFWorkbook;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.http.MediaType;
    import org.springframework.web.multipart.MultipartFile;
    
    import javax.servlet.http.HttpServletResponse;
    import java.io.File;
    import java.io.FileOutputStream;
    import java.io.IOException;
    import java.io.InputStream;
    import java.lang.reflect.Constructor;
    import java.lang.reflect.Field;
    import java.math.BigDecimal;
    import java.net.URLEncoder;
    import java.util.*;
    import java.util.concurrent.atomic.AtomicInteger;
    import java.util.stream.Collectors;
    import java.util.stream.Stream;
    
    public class ExcelUtils {
    
            private final static Logger log = LoggerFactory.getLogger(ExcelUtils.class);
    
            private final static String EXCEL2003 = "xls";
            private final static String EXCEL2007 = "xlsx";
    
        /**
         * 读取Excel文件
         * @param path
         * @param cls
         * @param file
         * @param <T>
         * @return
         */
            public static <T> List<T> readExcel(String path, Class<T> cls,MultipartFile file){
    
                String fileName = file.getOriginalFilename();
                //jx
                if("".equals(fileName)){
                    fileName = file.getName();
                }
                if (!fileName.matches("^.+\.(?i)(xls)$") && !fileName.matches("^.+\.(?i)(xlsx)$")) {
                    log.error("上传文件格式不正确");
                }
                List<T> dataList = new ArrayList<>();
                //03,07两种文档方式实现下面这个接口
                Workbook workbook = null;
                try {
                    InputStream is = file.getInputStream();
                    if (fileName.endsWith(EXCEL2007)) {
    //                FileInputStream is = new FileInputStream(new File(path));
                        workbook = new XSSFWorkbook(is);
                    }
                    if (fileName.endsWith(EXCEL2003)) {
    //                FileInputStream is = new FileInputStream(new File(path));
                        workbook = new HSSFWorkbook(is);
                    }
                    if (workbook != null) {
                        //类映射  注解 value-->bean columns
                        Map<String, List<Field>> classMap = new HashMap<>();
                        List<Field> fields = Stream.of(cls.getDeclaredFields()).collect(Collectors.toList());
                        fields.forEach(
                                field -> {
                                    ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
                                    if (annotation != null) {
                                        String value = annotation.value();
                                        if (StringUtils.isBlank(value)) {
                                            return;//return起到的作用和continue是相同的 语法
                                        }
                                        if (!classMap.containsKey(value)) {
                                            classMap.put(value, new ArrayList<>());
                                        }
                                        field.setAccessible(true);
                                        classMap.get(value).add(field);
                                    }
                                }
                        );
                        //索引-->columns
                        Map<Integer, List<Field>> reflectionMap = new HashMap<>(16);
                        //默认读取第一个sheet
                        Sheet sheet = workbook.getSheetAt(0);
    
                        boolean firstRow = true;
                        for (int i = sheet.getFirstRowNum(); i <= sheet.getLastRowNum(); i++) {
                            Row row = sheet.getRow(i);
                            //首行  提取注解
                            if (firstRow) {
                                for (int j = row.getFirstCellNum(); j <= row.getLastCellNum(); j++) {
                                    Cell cell = row.getCell(j);
                                    String cellValue = getCellValue(cell);
                                    if (classMap.containsKey(cellValue)) {
                                        reflectionMap.put(j, classMap.get(cellValue));
                                    }
                                }
                                firstRow = false;
                            } else {
                                //忽略空白行
                                if (row == null) {
                                    continue;
                                }
                                try {
                                    T t = cls.newInstance();
                                    //判断是否为空白行
                                    boolean allBlank = true;
                                    for (int j = row.getFirstCellNum(); j <= row.getLastCellNum(); j++) {
                                        if (reflectionMap.containsKey(j)) {
                                            Cell cell = row.getCell(j);
                                            String cellValue = getCellValue(cell);
                                            if (StringUtils.isNotBlank(cellValue)) {
                                                allBlank = false;
                                            }
                                            List<Field> fieldList = reflectionMap.get(j);
                                            fieldList.forEach(
                                                    x -> {
                                                        try {
                                                            handleField(t, cellValue, x);
                                                        } catch (Exception e) {
                                                            log.error(String.format("reflect field:%s value:%s exception!", x.getName(), cellValue), e);
                                                        }
                                                    }
                                            );
                                        }
                                    }
                                    if (!allBlank) {
                                        dataList.add(t);
                                    } else {
                                        log.warn(String.format("row:%s is blank ignore!", i));
                                    }
                                } catch (Exception e) {
                                    log.error(String.format("parse row:%s exception!", i), e);
                                }
                            }
                        }
                    }
                } catch (Exception e) {
                    log.error(String.format("parse excel exception!"), e);
                } finally {
                    if (workbook != null) {
                        try {
                            workbook.close();
                        } catch (Exception e) {
                            log.error(String.format("parse excel exception!"), e);
                        }
                    }
                }
                return dataList;
            }
    
            private static <T> void handleField(T t, String value, Field field) throws Exception {
                Class<?> type = field.getType();
                if (type == null || type == void.class || StringUtils.isBlank(value)) {
                    return;
                }
                if (type == Object.class) {
                    field.set(t, value);
                    //数字类型
                } else if (type.getSuperclass() == null || type.getSuperclass() == Number.class) {
                    if (type == int.class || type == Integer.class) {
                        field.set(t, NumberUtils.toInt(value));
                    } else if (type == long.class || type == Long.class) {
                        field.set(t, NumberUtils.toLong(value));
                    } else if (type == byte.class || type == Byte.class) {
                        field.set(t, NumberUtils.toByte(value));
                    } else if (type == short.class || type == Short.class) {
                        field.set(t, NumberUtils.toShort(value));
                    } else if (type == double.class || type == Double.class) {
                        field.set(t, NumberUtils.toDouble(value));
                    } else if (type == float.class || type == Float.class) {
                        field.set(t, NumberUtils.toFloat(value));
                    } else if (type == char.class || type == Character.class) {
                        field.set(t, CharUtils.toChar(value));
                    } else if (type == boolean.class) {
                        field.set(t, BooleanUtils.toBoolean(value));
                    } else if (type == BigDecimal.class) {
                        field.set(t, new BigDecimal(value));
                    }
                } else if (type == Boolean.class) {
                    field.set(t, BooleanUtils.toBoolean(value));
                } else if (type == Date.class) {
                    //
                    field.set(t, value);
                } else if (type == String.class) {
                    field.set(t, value);
                } else {
                    Constructor<?> constructor = type.getConstructor(String.class);
                    field.set(t, constructor.newInstance(value));
                }
            }
    
            private static String getCellValue(Cell cell) {
                if (cell == null) {
                    return "";
                }
                //更新,新版poi不建议使用以下方法,使用getCellTypeEnum代替getCellType
               /* if (cell.getCellType() == Cell.CELL_TYPE_NUMERIC) {
                    if (DateUtil.isCellDateFormatted(cell)) {
                        return HSSFDateUtil.getJavaDate(cell.getNumericCellValue()).toString();
                    } else {
                        return new BigDecimal(cell.getNumericCellValue()).toString();
                    }
                } else if (cell.getCellType() == Cell.CELL_TYPE_STRING) {
                    return StringUtils.trimToEmpty(cell.getStringCellValue());
                } else if (cell.getCellType() == Cell.CELL_TYPE_FORMULA) {
                    return StringUtils.trimToEmpty(cell.getCellFormula());
                } else if (cell.getCellType() == Cell.CELL_TYPE_BLANK) {
                    return "";
                } else if (cell.getCellType() == Cell.CELL_TYPE_BOOLEAN) {
                    return String.valueOf(cell.getBooleanCellValue());
                } else if (cell.getCellType() == Cell.CELL_TYPE_ERROR) {
                    return "ERROR";*/
                if (cell.getCellTypeEnum() == CellType.NUMERIC) {
                    if (DateUtil.isCellDateFormatted(cell)) {
                        return HSSFDateUtil.getJavaDate(cell.getNumericCellValue()).toString();
                    } else {
                        return new BigDecimal(cell.getNumericCellValue()).toString();
                    }
                } else if (cell.getCellTypeEnum() == CellType.STRING) {
                    return StringUtils.trimToEmpty(cell.getStringCellValue());
                } else if (cell.getCellTypeEnum() == CellType.FORMULA) {
                    return StringUtils.trimToEmpty(cell.getCellFormula());
                } else if (cell.getCellTypeEnum() == CellType.BLANK) {
                    return "";
                } else if (cell.getCellTypeEnum() == CellType.BOOLEAN) {
                    return String.valueOf(cell.getBooleanCellValue());
                } else if (cell.getCellTypeEnum() == CellType.ERROR) {
                    return "ERROR";
                } else {
                    return cell.toString().trim();
                }
    
            }
    
            public static <T> void writeExcel(HttpServletResponse response, List<T> dataList, Class<T> cls){
                Field[] fields = cls.getDeclaredFields();
                List<Field> fieldList = Arrays.stream(fields)
                        .filter(field -> {
                            ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
                            if (annotation != null && annotation.col() > 0) {
                                field.setAccessible(true);
                                return true;
                            }
                            return false;
                        }).sorted(Comparator.comparing(field -> {
                            int col = 0;
                            ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
                            if (annotation != null) {
                                col = annotation.col();
                            }
                            return col;
                        })).collect(Collectors.toList());
    
                Workbook wb = new XSSFWorkbook();
                Sheet sheet = wb.createSheet("Sheet1");
                AtomicInteger ai = new AtomicInteger();
                {
                    Row row = sheet.createRow(ai.getAndIncrement());
                    AtomicInteger aj = new AtomicInteger();
                    //写入头部
                    fieldList.forEach(field -> {
                        ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
                        String columnName = "";
                        if (annotation != null) {
                            columnName = annotation.value();
                        }
                        Cell cell = row.createCell(aj.getAndIncrement());
    
                        CellStyle cellStyle = wb.createCellStyle();
                        cellStyle.setFillForegroundColor(IndexedColors.WHITE.getIndex());
                        cellStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND);
                        cellStyle.setAlignment(HorizontalAlignment.CENTER);
    
                        Font font = wb.createFont();
                        font.setBold(false);
                        cellStyle.setFont(font);
                        cell.setCellStyle(cellStyle);
                        cell.setCellValue(columnName);
                    });
                }
                if (CollectionUtils.isNotEmpty(dataList)) {
                    dataList.forEach(t -> {
                        Row row1 = sheet.createRow(ai.getAndIncrement());
                        AtomicInteger aj = new AtomicInteger();
                        fieldList.forEach(field -> {
                            Class<?> type = field.getType();
                            Object value = "";
                            try {
                                value = field.get(t);
                            } catch (Exception e) {
                                e.printStackTrace();
                            }
                            Cell cell = row1.createCell(aj.getAndIncrement());
                            if (value != null) {
                                if (type == Date.class) {
                                    cell.setCellValue(value.toString());
                                } else {
                                    cell.setCellValue(value.toString());
                                }
                                cell.setCellValue(value.toString());
                            }
                        });
                    });
                }
                //冻结窗格
                wb.getSheet("Sheet1").createFreezePane(0, 1, 0, 1);
                //浏览器下载excel
                buildExcelDocument("jocytest.xlsx",wb,response);
                //生成excel文件
    //        buildExcelFile(".\default.xlsx",wb);
            }
    
            /**
             * 浏览器下载excel
             * @param fileName
             * @param wb
             * @param response
             */
    
            private static  void  buildExcelDocument(String fileName, Workbook wb,HttpServletResponse response){
                try {
                    response.setContentType(MediaType.APPLICATION_OCTET_STREAM_VALUE);
                    response.setHeader("Content-Disposition", "attachment;filename="+URLEncoder.encode(fileName, "utf-8"));
                    response.flushBuffer();
                    wb.write(response.getOutputStream());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
    
            /**
             * 生成excel文件
             * @param path 生成excel路径
             * @param wb
             */
            private static  void  buildExcelFile(String path, Workbook wb){
    
                File file = new File(path);
                if (file.exists()) {
                    file.delete();
                }
                try {
                    wb.write(new FileOutputStream(file));
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
    }
    
    

    2.自定义的注解

    import java.lang.annotation.*;
    
    /**
     * 定义了实体类所需要的Bean
     */
    
    @Target({ElementType.FIELD}) //该注解作用在域上
    /**
     * 生命周期
     * 注解不仅被保存到class文件中,jvm加载class文件之后,仍然存在,
     * 保存到class对象中,可以通过反射来获取
     */
    
    @Retention(RetentionPolicy.RUNTIME)
    
    @Documented
    public @interface ExcelColumn {
    
        String value() default "";
    
        int col() default 0;
    }
    

    三、定义测试实体类

    import lombok.Setter;
    import org.hibernate.annotations.GenericGenerator;
    import javax.persistence.*;
    
    @Entity
    @Table(name = "Excel")
    @Getter
    @Setter
    public class TestExcel {
        @Id
        @GeneratedValue(generator = "uuid")
        @GenericGenerator(name = "uuid",strategy = "uuid")
        private String id;
        @ExcelColumn(value = "excelId",col = 1)
        private String excelId;
        @ExcelColumn(value = "markId", col = 2)
        private String markId;
    
        @ExcelColumn(value = "toaluv", col = 3)
        private String toaluv;
    
        @ExcelColumn(value = "date", col = 4)
        private String date;
    
        @ExcelColumn(value = "clientVer", col = 5)
        private String clientVer;
    }
    

    四、service实现插入、查询方法

    dao层直接继承了JpaRepository接口,使用时pom文件中添加jpa的引用。

    public interface ExcelDao extends JpaRepository<TestExcel,String> {
    }
    

    在dao基础上,service的实现如下:

    Service(value = "excelService")
    public class ExcelServiceImpl implements ExcelService {
    
        @Autowired
        ExcelDao excelDao;
        @Override
        public List<TestExcel> findAll() {
            return excelDao.findAll();
        }
    
        public void saveAll(List<TestExcel> excels){
            excelDao.saveAll(excels);
        }
    }
    

    五、controller进行测试

    import **.excelImportExport.entity.TestExcel;
    import **.excelImportExport.service.ExcelService;
    import **.excelImportExport.utils.ExcelUtils;
    import com.alibaba.fastjson.JSON;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.mock.web.MockMultipartFile;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.PostMapping;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    import org.springframework.web.multipart.MultipartFile;
    
    import javax.servlet.http.HttpServletResponse;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.IOException;
    import java.util.List;
    
    @RestController
    @RequestMapping("/excel")
    public class ExcelController  {
    
        @Autowired
        ExcelService excelService;
    
        /**
         * Excel导出功能
         * @param response
         * @throws IOException
         */
        @GetMapping(value = "/exportExcel")
        public void exportExcel(HttpServletResponse response)  throws IOException {
    
            List<TestExcel> resultList = excelService.findAll();
    
            long t1 = System.currentTimeMillis();
            ExcelUtils.writeExcel(response, resultList, TestExcel.class);
            long t2 = System.currentTimeMillis();
            System.out.println(String.format("write over! cost:%sms", (t2 - t1)));
        }
    
        /**
         * Excel导入功能
         * @param file
         * @throws IOException
         */
    
        @PostMapping(value = "/readExcel")
        public void readExcel(MultipartFile file) throws IOException {
    
           //测试时用此方法将File->MultipartFile,上传文件时直接调用readExcel方法即可
            MockMultipartFile mockMultipartFile    =
                    new MockMultipartFile("jocy.xlsx", new FileInputStream(new File("/Users/Downloads/jocy.xlsx")));
            long t1 = System.currentTimeMillis();
            //List<TestExcel> list = ExcelUtils.readExcel("", TestExcel.class,file);
            List<TestExcel> list = ExcelUtils.readExcel("", TestExcel.class,mockMultipartFile);
            long t2 = System.currentTimeMillis();
            excelService.saveAll(list);
            System.out.println(String.format("read over! cost:%sms", (t2 - t1)));
            list.forEach(
                    b -> System.out.println(JSON.toJSONString(b))
            );
        }
    }
    
     
     
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  • 原文地址:https://www.cnblogs.com/xichji/p/11683770.html
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