引入依赖
<!-- EasyExcel -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>easyexcel</artifactId>
<version>2.2.7</version>
</dependency>
<!--csv文件操作-->
<dependency>
<groupId>net.sourceforge.javacsv</groupId>
<artifactId>javacsv</artifactId>
<version>2.0</version>
</dependency>数据读取监听
导入数据时，程序解析和读取数据用，必须要！！！
import com.alibaba.excel.context.AnalysisContext;
import com.alibaba.excel.event.AnalysisEventListener;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
/**
* Excel数据解析监听器， 数据解析方法异步执行
* @param <T> Excel中数据的类型
*/
@Getter
@Setter
@NoArgsConstructor
public class ExcelListener<T> extends AnalysisEventListener<T> {
// 加入一个判断标签，判断数据是否已经读取完
private volatile boolean retryLock = false;
// 解析完成后的数据集合, 监听对象初始化之后，立即初始化集合对象
private final List<T> dataList = new ArrayList<>();
// 每次最多导入条数
private final int batchSize = 2000;
/**
* 获取解析后的数据集合， 如果数据还没有被解析完成，会对读取该集合的线程进行阻塞，直到数据读取完成之后，进行解锁。
* 如果一次导入数据超过batchSize条，则以抛异常的形式阻止导入数据
* @return 解析后的数据集合
*/
public List<T> getDataList() {
while (true){
if (retryLock){
if (dataList.size() > batchSize){
// 手动清空数据内存数据，减少内存消耗
dataList.clear();
throw new RuntimeException("一次最多导入"+ batchSize +"条数据");
} else {
return dataList;
}
}
}
}
/**
* Excel每解析一行数据，就会调用一次该方法
* @param data
* one row value. Is is same as {@link AnalysisContext#readRowHolder()}
* @param context
* analysis context
*/
@Override
public void invoke(T data, AnalysisContext context) {
dataList.add(data);
}
/**
* 读取表头内容
* @param headMap 表头部数据
* @param context 数据解析上下文
*/
@Override
public void invokeHeadMap(Map<Integer, String> headMap, AnalysisContext context) {
//System.out.println("表头：" + headMap);
}
/**
* 流中的数据解析完成之后，就会调用此方法
* @param context
*/
@Override
public void doAfterAllAnalysed(AnalysisContext context) {
// 数据解析完成，解锁
retryLock = true;
}
/**
* 解析过程如果发生异常，会调用此方法
* @param exception
* @param context
*/
@Override
public void onException(Exception exception, AnalysisContext context){
throw new RuntimeException("Excel数据异常，请检查或联系管理员！");
}
}
Excel工具类
根据EasyExcel Model 导出工具类,CSV支持获取ExcelPropert
package net.demo.excel.common.util;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.metadata.BaseRowModel;
import com.alibaba.excel.metadata.Sheet;
import com.alibaba.excel.support.ExcelTypeEnum;
import com.csvreader.CsvWriter;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.lang.reflect.Field;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.List;
/**
* @desc: 根据EasyExcel Model 导出工具类
* @Author: Swift
* @Date: 2019-08-26 15:18
*/
public class ExportUtil {
/**
* 获取ExcelProperty Value
* @return
*/
public static <T extends BaseRowModel> String[] getFieldNames(Class<T> tClass) {
Field[] fields = tClass.getDeclaredFields();
List<String> headers = new ArrayList<>();
for (Field field: fields) {
ExcelProperty property = field.getAnnotation(ExcelProperty.class);
if (property != null) {
String[] s = property.value();
if (s.length > 0) {
headers.add(s[0]);
}
}
}
String[] strings = new String[headers.size()];
headers.toArray(strings);
return strings;
}
/**
* 获取filedName
* @param vo
* @param <T>
* @return
*/
public static <T extends BaseRowModel> String[] getFields(T vo) {
Field[] fields = vo.getClass().getDeclaredFields();
List<String> columns = new ArrayList<>();
for (Field field: fields) {
ExcelProperty property = field.getAnnotation(ExcelProperty.class);
if (property != null) {
try {
field.setAccessible(true);
columns.add(field.get(vo)==null ? "" : field.get(vo).toString());
} catch (IllegalAccessException e) {
e.printStackTrace();
throw new RuntimeException("写入内容到csv失败!");
}
}
}
String[] strings = new String[columns.size()];
columns.toArray(strings);
return strings;
}
public static <T extends BaseRowModel> void export(String type, List<T> vos, HttpServletResponse response, Class<T> t
) throws IOException {
Boolean isCsv = "csv".equals(type);
String fileName = "data" + CalendarUtils.getCurrentTime();
response.setContentType("multipart/form-data");
response.setCharacterEncoding("utf-8");
if (isCsv) {
fileName += ".csv";
} else {
fileName += ".xlsx";
}
response.setHeader("Content-disposition", "attachment;filename=" + fileName);
ServletOutputStream outputStream = response.getOutputStream();
if (isCsv) {
CsvWriter csvWriter = new CsvWriter(outputStream, ',', Charset.forName("GBK"));
csvWriter.writeRecord(getFieldNames(t));
for (T vo : vos) {
String[] fields = getFields(vo);
csvWriter.writeRecord(fields);
}
csvWriter.close();
} else {
ExcelWriter excelWriter = new ExcelWriter(outputStream, ExcelTypeEnum.XLSX, true);
Sheet sheet = new Sheet(1, 0, t);
excelWriter.write(vos, sheet);
sheet.setAutoWidth(true);
excelWriter.finish();
}
outputStream.flush();
}
public static <T extends BaseRowModel> void export(String type,String fileName, List<T> vos, HttpServletResponse response, Class<T> t
) throws IOException {
Boolean isCsv = "csv".equals(type);
// String fileName = "data" + CalendarUtils.getCurrentTime();
response.setContentType("multipart/form-data");
response.setCharacterEncoding("utf-8");
if (isCsv) {
fileName += ".csv";
} else {
fileName += ".xlsx";
}
response.setHeader("Content-disposition", "attachment;filename=" + fileName);
ServletOutputStream outputStream = response.getOutputStream();
if (isCsv) {
CsvWriter csvWriter = new CsvWriter(outputStream, ',', Charset.forName("GBK"));
csvWriter.writeRecord(getFieldNames(t));
for (T vo : vos) {
String[] fields = getFields(vo);
csvWriter.writeRecord(fields);
}
csvWriter.close();
} else {
ExcelWriter excelWriter = new ExcelWriter(outputStream, ExcelTypeEnum.XLSX, true);
Sheet sheet = new Sheet(1, 0, t);
excelWriter.write(vos, sheet);
sheet.setAutoWidth(true);
excelWriter.finish();
}
outputStream.flush();
}
/**
* 根据Excel模板，批量导入数据
* @param file 导入的Excel
* @param clazz 解析的类型
* @return 解析完成的数据
*/
public static List<?> importExcel(MultipartFile file, Class<?> clazz){
if (file == null || file.isEmpty()){
throw new RuntimeException("没有文件或者文件内容为空！");
}
List<Object> dataList = null;
BufferedInputStream ipt = null;
try {
InputStream is = file.getInputStream();
// 用缓冲流对数据流进行包装
ipt = new BufferedInputStream(is);
// 数据解析监听器
ExcelListener<Object> listener = new ExcelListener<>();
// 读取数据
EasyExcel.read(ipt, clazz,listener).sheet().doRead();
// 获取去读完成之后的数据
dataList = listener.getDataList();
} catch (Exception e){
log.error(String.valueOf(e));
throw new RuntimeException("数据导入失败！" + e);
}
return dataList;
}
}WriterFactory
导出工厂实现了xlsx与csv 两种方式
package net.demo.excel.common.export;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import javax.servlet.http.HttpServletResponse;
import lombok.Data;
import lombok.extern.slf4j.Slf4j;
import net.demo.excel.common.constants.Constants;
import net.demo.excel.common.constants.ExportTypeEnum;
import net.demo.excel.common.export.csv.CsvExport;
import net.demo.excel.common.export.excel.ExcelExport;
/**
* 导出工厂
*/
@Data
@Slf4j
public class WriterFactory {
/**
* 返回文件流方式
*
* @param key
* @param fileName
* @param response
* @return
*/
public static ExportWriter getExportWriter(String key, String fileName,
HttpServletResponse response) {
ExportWriter exportWriter = null;
try {
OutputStream os = response.getOutputStream();
ExportTypeEnum exportTypeEnum = ExportTypeEnum.findByType(key);
fileName = fileName + exportTypeEnum.getSuffix();
exportWriter = generateExportWriter(exportTypeEnum, os);
response.setContentType("application/force-download");
// 设置文件名
response.addHeader("Content-Disposition",
"attachment;filename=" + URLEncoder.encode(fileName, "utf-8"));
} catch (UnsupportedEncodingException e) {
log.error("UnsupportedEncoding:", e);
} catch (IOException e) {
log.error("IOException:", e);
}
return exportWriter;
}
/**
* 输出到文件方式
*
* @param key
* @param fileName
* @return
*/
public static ExportWriter getExportWriter(String key, String fileName)
throws FileNotFoundException {
ExportTypeEnum exportTypeEnum = ExportTypeEnum.findByType(key);
String filePath =
Constants.EXPORT_TMP_DIR + File.separator + fileName + exportTypeEnum.getSuffix();
File file = new File(filePath);
OutputStream os = new FileOutputStream(file);
ExportWriter exportWriter = generateExportWriter(exportTypeEnum, os);
exportWriter.setFilePath(filePath);
return exportWriter;
}
private static ExportWriter generateExportWriter(ExportTypeEnum exportTypeEnum, OutputStream os) {
ExportWriter exportWriter = null;
switch (exportTypeEnum) {
case EXCEL:
exportWriter = new ExcelExport(os);
break;
case CSV:
exportWriter = new CsvExport(os);
break;
default:
}
return exportWriter;
}
}ExportModel抽象类
package net.demo.excel.common.export.model;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.metadata.Sheet;
import com.csvreader.CsvWriter;
/**
* 抽象实体
*/
public abstract class ExportModel {
public abstract ExcelWriter getExcelWriter();
public abstract Sheet getSheet();
public abstract CsvWriter getCsvWriter();
}
CsvModel 实体类
package net.demo.excel.common.export.csv.model;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.metadata.Sheet;
import com.csvreader.CsvWriter;
import lombok.Data;
import net.demo.excel.common.export.model.ExportModel;
/**
* csv相关实体
*/
@Data
public class CsvModel extends ExportModel {
private CsvWriter csvWriter;
@Override
public ExcelWriter getExcelWriter() {
return null;
}
@Override
public Sheet getSheet() {
return null;
}
@Override
public CsvWriter getCsvWriter() {
return csvWriter;
}
public CsvModel(CsvWriter csvWriter) {
this.csvWriter = csvWriter;
}
}ExcelModel 实体类
package net.demo.excel.common.export.excel.model;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.metadata.Sheet;
import com.csvreader.CsvWriter;
import lombok.Data;
import net.demo.excel.common.export.model.ExportModel;
/**
* excel,csv相关实体
*/
@Data
public class ExcelModel extends ExportModel {
private ExcelWriter excelWriter;
private Sheet sheet;
@Override
public ExcelWriter getExcelWriter() {
return excelWriter;
}
@Override
public Sheet getSheet() {
return sheet;
}
@Override
public CsvWriter getCsvWriter() {
return null;
}
public ExcelModel(ExcelWriter excelWriter, Sheet sheet) {
this.excelWriter = excelWriter;
this.sheet = sheet;
}
}ExportWriter接口
package net.demo.excel.common.export;
import com.alibaba.excel.metadata.BaseRowModel;
import com.alibaba.fastjson.JSONArray;
import java.util.List;
import net.demo.excel.common.bean.Column;
/**
* 导出接口
*/
public interface ExportWriter {
public static final int EXPORT_PAGE_SIZE = 5000;
/**
* 写入表头 结构为{"code":"字段名","title":"显示名"}
*
* @param columnList
*/
public void writeTitle(List<Column> columnList);
public <T extends BaseRowModel> void writeTitle(Class<T> t);
/**
* 添加内容 data的Map结构为{"字段名":"字段值"}
*
* @param dataList
* @param columnList
*/
public void appendContent(JSONArray dataList, List<Column> columnList);
public <T extends BaseRowModel> void appendContent(List<T> vos, Class<T> t);
/**
* 关闭文件流
*/
public void close();
public String getFilePath();
public void setFilePath(String filePath);
}Column
package net.demo.excel.common.bean;
import lombok.AllArgsConstructor;
import lombok.Data;
@Data
@AllArgsConstructor
public class Column {
/**
* 英文名称
*/
private String code;
/**
* 中文名称
*/
private String title;
}ExcelExport实现类
package net.demo.excel.common.export.excel;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.metadata.BaseRowModel;
import com.alibaba.excel.metadata.Sheet;
import com.alibaba.excel.support.ExcelTypeEnum;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
import lombok.Data;
import lombok.extern.slf4j.Slf4j;
import net.demo.excel.common.bean.Column;
import net.demo.excel.common.export.ExportWriter;
import net.demo.excel.common.export.excel.model.ExcelModel;
import net.demo.excel.common.export.model.ExportModel;
import net.demo.excel.common.util.ExportUtil;
import java.io.*;
import java.util.ArrayList;
import java.util.List;
/**
* excel具体实现
*/
@Slf4j
@Data
public class ExcelExport implements ExportWriter {
private ExportModel model;
private OutputStream os;
private String filePath;
/**
* 初始化
*
* @param os
*/
public ExcelExport(OutputStream os) {
ExcelWriter writer = new ExcelWriter(os, ExcelTypeEnum.XLSX);
Sheet sheet = new Sheet(1, 0);
sheet.setSheetName(String.valueOf(1));
this.model = new ExcelModel(writer, sheet);
this.os = os;
}
/**
* 写标题
*
* @param columnList
*/
@Override
public void writeTitle(List<Column> columnList) {
List<List<String>> dataList = new ArrayList<List<String>>();
//组装标题行
for (int i = 0; i < columnList.size(); i++) {
List<String> titleList = new ArrayList<String>();
Column column = columnList.get(i);
String title = column.getTitle();
titleList.add(title);
dataList.add(titleList);
}
model.getSheet().setHead(dataList);
}
/**
* 写标题
*/
@Override
public <T extends BaseRowModel> void writeTitle(Class<T> t) {
List<List<String>> dataList = new ArrayList<List<String>>();
String[] columns = ExportUtil.getFieldNames(t);
//组装标题行
for (int i = 0; i < columns.length; i++) {
List<String> titleList = new ArrayList<String>();
String title = columns[i];
titleList.add(title);
dataList.add(titleList);
}
model.getSheet().setHead(dataList);
}
/**
* 内容追加
*
* @param dataList
* @param columnList
*/
@Override
public void appendContent(JSONArray dataList, List<Column> columnList) {
List<List<String>> dataArray = new ArrayList<List<String>>();
//组装数据行
for (Object obj : dataList) {
JSONObject json = (JSONObject) JSONObject.toJSON(obj);
List<String> rowList = new ArrayList<>();
for (int j = 0; j < columnList.size(); j++) {
Column columnMap = columnList.get(j);
String code = columnMap.getCode();
Object value = json.get(code);
String valueStr = value == null ? "" : value.toString();
rowList.add(valueStr);
}
dataArray.add(rowList);
}
model.getExcelWriter().write1(dataArray, model.getSheet());
}
/**
* 追加内容
*
* @param vos
* @param t
* @param <T>
*/
@Override
public <T extends BaseRowModel> void appendContent(List<T> vos, Class<T> t) {
model.getExcelWriter().write(vos, model.getSheet());
model.getSheet().setAutoWidth(true);
}
/**
* 关闭流
*/
@Override
public void close() {
ExcelWriter writer = model.getExcelWriter();
try {
if (writer != null) {
writer.finish();
}
os.close();
} catch (IOException e) {
log.error("os close error", e);
}
}
@Override
public String getFilePath() {
return filePath;
}
@Override
public void setFilePath(String filePath) {
this.filePath = filePath;
}
}CsvExport实现类
package net.demo.excel.common.export.csv;
import com.alibaba.excel.metadata.BaseRowModel;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
import com.csvreader.CsvWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.List;
import lombok.Data;
import lombok.extern.slf4j.Slf4j;
import net.demo.excel.common.bean.Column;
import net.demo.excel.common.export.ExportWriter;
import net.demo.excel.common.export.csv.model.CsvModel;
import net.demo.excel.common.export.model.ExportModel;
import net.demo.excel.common.util.ExportUtil;
/**
* csv具体实现
*/
@Slf4j
@Data
public class CsvExport implements ExportWriter {
private ExportModel model;
private OutputStream os;
private String filePath;
/**
* 初始化
*
* @param os
*/
public CsvExport(OutputStream os) {
CsvWriter csvWriter = new CsvWriter(os, ',', Charset.forName("GBK"));
this.model = new CsvModel(csvWriter);
this.os = os;
}
/**
* 写标题
*
* @param columnList
*/
@Override
public void writeTitle(List<Column> columnList) {
String[] headers = new String[columnList.size()];
for (int i = 0; i < columnList.size(); i++) {
Column tmp = columnList.get(i);
headers[i] = tmp.getTitle();
}
try {
model.getCsvWriter().writeRecord(headers);
} catch (IOException e) {
log.error("写入标题到csv失败!", e);
throw new RuntimeException("写入标题到csv失败!");
}
}
@Override
public <T extends BaseRowModel> void writeTitle(Class<T> t){
try {
model.getCsvWriter().writeRecord(ExportUtil.getFieldNames(t));
} catch (IOException e) {
log.error("写入标题到csv失败!", e);
throw new RuntimeException("写入标题到csv失败!");
}
}
/**
* 内容追加
*
* @param dataList
* @param columnList
*/
@Override
public void appendContent(JSONArray dataList, List<Column> columnList) {
String[] content = null;
List<String> codeList = new ArrayList<String>();
for (int i = 0; i < columnList.size(); i++) {
Column tmp = columnList.get(i);
String code = tmp.getCode();
codeList.add(code);
}
try {
for (Object obj : dataList) {
JSONObject json = (JSONObject) JSONObject.toJSON(obj);
content = new String[codeList.size()];
for (int i = 0; i < codeList.size(); i++) {
String code = codeList.get(i);
Object value = json.get(code);
content[i] = value == null ? "" : value.toString();
}
model.getCsvWriter().writeRecord(content);
}
} catch (Exception e) {
log.error("写入内容到csv失败!", e);
throw new RuntimeException("写入内容到csv失败!");
}
}
@Override
public <T extends BaseRowModel> void appendContent(List<T> vos, Class<T> t) {
try {
for (T vo : vos) {
String[] fields = ExportUtil.getFields(vo);
model.getCsvWriter().writeRecord(fields);
}
} catch (IOException e) {
log.error("写入内容到csv失败!", e);
throw new RuntimeException("写入内容到csv失败!");
}
}
/**
* 关闭
*/
@Override
public void close() {
CsvWriter csvWriter = model.getCsvWriter();
if (csvWriter != null) {
csvWriter.close();
}
try {
os.close();
} catch (IOException e) {
log.error("os close error", e);
}
}
@Override
public String getFilePath() {
return filePath;
}
@Override
public void setFilePath(String filePath) {
this.filePath = filePath;
}
}创建导入数据模板类
import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.annotation.write.style.ColumnWidth;
import lombok.Data;
import lombok.experimental.Accessors;
import javax.validation.constraints.NotEmpty;
import java.io.Serializable;
/**
* 数据导入的Excel模板实体
*/
@Data
public class ImportExcelVo implements Serializable {
private static final long serialVersionUID = 1L;
@ColumnWidth(20)
@ExcelProperty(value = "公司名称", index = 0)
private String name;
@ColumnWidth(20)
@ExcelProperty(value = "公司联系电话", index = 1)
private String phone;
@ColumnWidth(28)
@ExcelProperty(value = "公司统一社会信用代码", index = 2)
private String creditCode;
@ColumnWidth(15)
@ExcelProperty(value = "区域", index = 3)
private String province;
@ColumnWidth(15)
@ExcelProperty(value = "公司法人", index = 4)
private String legalPerson;
@ExcelProperty(value = "备注", index = 5)
private String remark;
}创建数据导出模板
import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.metadata.BaseRowModel;
import com.alibaba.excel.annotation.write.style.ColumnWidth;
import lombok.Data;
import lombok.experimental.Accessors;
import java.io.Serializable;
/**
* 资质信息导出实体
*/
@Data // Lombok注解，用于生成getter setter
@Accessors(chain = true) //Lombok注解，链式赋值使用
public class ExportExcelVo extends BaseRowModel {
private static final long serialVersionUID = 1L;
@ColumnWidth(25)
@ExcelProperty(value = "企业名称", index = 0)
private String name;
@ColumnWidth(25)
@ExcelProperty(value = "社会统一信用代码", index = 1)
private String creditCode;
@ColumnWidth(15)
@ExcelProperty(value = "曾用名", index = 2, converter = NullConverter.class)
private String formerName;
@ColumnWidth(15)
@ExcelProperty(value = "公司法人", index = 3)
private String legalPerson;
@ExcelProperty(value = "区域", index = 4)
private String province;
@ExcelProperty(value = "录入时间", index = 5)
private String createTime;
@ColumnWidth(15)
@ExcelProperty(value = "公司股东", index = 6)
private String stockholder;
@ExcelProperty(value = "企业联系方式", index = 7)
private String contact;
}使用方法
/**
* Excel批量导入数据
*
* @param file 导入文件
*/
@RequestMapping(value = "/import", method = RequestMethod.POST)
public CommonResponse<String> importEvents(MultipartFile file) {
try {
List<?> list = ExportUtil.importExcel(file, ImportExcelVo.class);
System.out.println(list);
return CommonResponse.success("数据导入完成");
} catch (Exception e) {
return CommonResponse.error("数据导入失败！" + e.getMessage());
}
}
//生成excel文件
try {
exportWriter = WriterFactory.getExportWriter(
dto.getExportType() == null ? "csv" : dto.getExportType(), fileName);
exportWriter.writeTitle(PhoneExportVO.class);
exportWriter.appendContent(list, PhoneExportVO.class);
} catch (Exception e) {
log.error("导出失败", e);
throw new BaseException("导出失败");
} finally {
if (exportWriter != null) {
exportWriter.close();
}
}
ExportWriter exportWriter = WriterFactory.getExportWriter(exportType, fileName);
List<Column> columns = trunkAreaVOResp.getColumns();
exportWriter.writeTitle(columns);
JSONArray dataList = (JSONArray) JSON.toJSON(trunkAreaVOResp.getTrunkArea());
exportWriter.appendContent(dataList, columns);
exportWriter.close();EasyExcel自定义转换器Converter
Timestamp 转换器
package com.yandype.util.easyExcel;
import java.sql.Timestamp;
import java.text.SimpleDateFormat;
import com.alibaba.excel.converters.Converter;
import com.alibaba.excel.enums.CellDataTypeEnum;
import com.alibaba.excel.metadata.GlobalConfiguration;
import com.alibaba.excel.metadata.data.WriteCellData;
import com.alibaba.excel.metadata.property.ExcelContentProperty;
public class TimestampConverter implements Converter<Timestamp>{
@Override
public Class<Timestamp> supportJavaTypeKey() {
return Timestamp.class;
}
@Override
public CellDataTypeEnum supportExcelTypeKey() {
return CellDataTypeEnum.STRING;
}
@Override
public WriteCellData<String> convertToExcelData(Timestamp timestamp, ExcelContentProperty contentProperty,
GlobalConfiguration globalConfiguration) throws Exception {
return new WriteCellData<String>(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(timestamp));
}
}NullConverter
import com.alibaba.excel.converters.Converter;
import com.alibaba.excel.enums.CellDataTypeEnum;
import com.alibaba.excel.metadata.CellData;
import com.alibaba.excel.metadata.GlobalConfiguration;
import com.alibaba.excel.metadata.property.ExcelContentProperty;
public class NullConverter implements Converter<String> {
/**
* 回到 Java 中的对象类型
*
* @return 支持 Java 类
*/
@Override
public Class supportJavaTypeKey() {
return String.class;
}
/**
* * 返回 excel 中的对象枚举
* * @return 支持 {@link Cell DataTypeEnum}
* */
@Override
public CellDataTypeEnum supportExcelTypeKey() {
return CellDataTypeEnum.STRING;
}
/**
* 将excel对象转换为Java对象
*
* @param cellData
* Excel 单元格数据。NotNull。
* @param contentProperty
* 内容属性。可空。
* @param globalConfiguration
* 全局配置。NotNull。
* @return 要放入 Java 对象的数据
* @抛出异常
* 例外。
*/
@Override
public String convertToJavaData(CellData cellData, ExcelContentProperty contentProperty, GlobalConfiguration globalConfiguration) throws Exception {
return "-".equals(cellData.getStringValue()) ? null : cellData.getStringValue();
}
/**
* 将 Java 对象转换为 excel 对象
*
* @参数值
* Java 数据.NotNull。
* @param contentProperty
* 内容属性。可空。
* @param globalConfiguration
* 全局配置。NotNull。
* @return 数据放入 Excel
* @抛出异常
* 例外。
*/
@Override
public CellData convertToExcelData(String value, ExcelContentProperty contentProperty, GlobalConfiguration globalConfiguration) throws Exception {
return new CellData<>(null == value ? "-" : value);
}
}
使用方法一
每个字段都要添加@ExcelProperty(converter = NullConverter.class)代码，如果遇到大量的数据字段去填充处理会增加很多工作量。转换器仅支持需要被处理的数据字段,也就是适用于从数据库查询出来已有的数据，如日期格式或性别字段做转换时才生效
使用方法二
File uploadFile = File.createTempFile("export", ".xlsx");
String templateFilePath = systemUrl + "/template/exportPublishShop.xlsx";
ExcelWriterSheetBuilder excelWriterSheetBuilder =
EasyExcel.write(uploadFile).registerConverter(new TimestampConverter()).withTemplate(templateFilePath).sheet();
List<Map<String, String>> productList = 查询数据数据
// productList 如果数据量很大一定要做分页查询，避免占用内存过大
excelWriterSheetBuilder.doFill(productList);
