最近在做Excel导入功能，是一种一对多的数据，涉及到合并单元格的，考虑到使用poi去学，要自己去做处理，所以，看看有什么开源的框架，找到两个合适的框架，一个是easypoi是能支持这种的，这个框架提供了特定注解；还有一种是EasyExcel，阿里开源的，不过功能相对没easypoi齐全，比如这种合并单元格数据导入，就没有特定的注解，不过通过搜索资料，是可以实现的，不过要自己写工具类做处理，工具类整理自网上教程
不过在官网看到EasyExcel更专注于性能和易用，虽然功能支持不如easypoi，所以还是想尝试使用一下这个框架。所以，业务比较复杂，可以使用easypoi，业务简单点可以使用easyexcel，图来自EasyExcel官网：
加上easyexcel配置：
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>easyexcel</artifactId>
<version>2.2.10</version>
</dependency>
加上ExcelProperty注解，加上value和index，index是excel对应的列
package com.example.easyexcel.model.dto;
import com.alibaba.excel.annotation.ExcelProperty;
import lombok.Data;
import org.hibernate.validator.constraints.Length;
import javax.validation.constraints.NotBlank;
public class UserExcelDto {
(value = "序号",index = 0)
(message = "序号必须填！")
private String seq;
(value = "用户名" ,index = 1)
(message = "用户名必须填！")
private String name;
(value = "密码", index = 2)
(min = 0 , max = 8 , message = "密码最多8位！")
private String password;
(value = "描述",index = 3)
private String addressName;
(value = "邮政编码",index = 4)
private String code;
}
package com.common.excel;
import cn.hutool.core.util.ReflectUtil;
import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONUtil;
import com.alibaba.excel.context.AnalysisContext;
import com.alibaba.excel.event.AnalysisEventListener;
import com.alibaba.excel.metadata.CellExtra;
import lombok.extern.slf4j.Slf4j;
import java.util.ArrayList;
import java.util.List;
public class EasyExcelListener<T> extends AnalysisEventListener<T> {
private List<T> datas;
private Integer rowIndex;
private List<CellExtra> extraMergeInfoList;
public EasyExcelListener(Integer rowIndex) {
this.rowIndex = rowIndex;
datas = new ArrayList<>();
extraMergeInfoList = new ArrayList<>();
}
public void invoke(T data, AnalysisContext context) {
// 是否忽略空行数据，因为自己要做数据校验，所以还是加上，可以根据业务情况使用
context.readWorkbookHolder().setIgnoreEmptyRow(false);
ReflectUtil.invoke(data, "setIndex", StrUtil.toString(context.readRowHolder().getRowIndex()));
datas.add(data);
}
public void doAfterAllAnalysed(AnalysisContext context) {
log.info("所有数据解析完成！");
}
public void extra(CellExtra extra, AnalysisContext context) {
switch (extra.getType()) {
case MERGE:
if (extra.getRowIndex() >= rowIndex) {
extraMergeInfoList.add(extra);
}
break;
default:
}
}
public List<T> getData() {
return datas;
}
public List<CellExtra> getExtraMergeInfoList() {
return extraMergeInfoList;
}
}
EasyExcel.read(file.getInputStream(), UserExcelDto.class, easyExcelListener)
.extraRead(CellExtraTypeEnum.MERGE)
.sheet(sheetNo)
.headRowNumber(headRowNumber)
.doRead();
System.out.println(JSONUtil.toJsonPrettyStr(easyExcelListener.getData()));
List<CellExtra> extraMergeInfoList = easyExcelListener.getExtraMergeInfoList();
EasyExcel Merge默认数据读取，这种情况，那些非合并的数据，比如姓名，密码这些数据，只会在第一个附上，框架之后的读取，不能读取到
[
{
"code": "510000",
"password": "********",
"name": "user1",
"addressName": "广州天河区",
"seq": "1"
},
{
"code": "510001",
"addressName": "广州天河区"
},
{
"code": "510002",
"password": "***",
"name": "user2",
"addressName": "广州天河区",
"seq": "2"
}
]
所以借助网上一个工具类实现，具体参考ExcelMergeHelper
工具类，思路也是读取excel数据，然后读取ExcelProperty注解，注意必须加上index，通过反射机制读取数据
package com.example.easyexcel.core.excel;
import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.enums.CellExtraTypeEnum;
import com.alibaba.excel.metadata.CellExtra;
import com.alibaba.excel.util.CollectionUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.lang.reflect.Field;
import java.util.List;
public class ExcelMergeHelper<T> {
private static final Logger LOGGER = LoggerFactory.getLogger(ExcelMergeHelper.class);
/**
* 返回解析后的List
*
* @param: fileName 文件名
* @param: clazz Excel对应属性名
* @param: sheetNo 要解析的sheet
* @param: headRowNumber 正文起始行
* @return java.util.List<T> 解析后的List
*/
public List<T> getList(String fileName, Class<T> clazz, Integer sheetNo, Integer headRowNumber) {
UserEasyExcelListener<T> listener = new UserEasyExcelListener<>(headRowNumber);
try {
EasyExcel.read(fileName, clazz, listener).extraRead(CellExtraTypeEnum.MERGE).sheet(sheetNo).headRowNumber(headRowNumber).doRead();
} catch (Exception e) {
LOGGER.error(e.getMessage());
}
List<CellExtra> extraMergeInfoList = listener.getExtraMergeInfoList();
if (CollectionUtils.isEmpty(extraMergeInfoList)) {
return listener.getData();
}
List<T> data = explainMergeData(listener.getData(), extraMergeInfoList, headRowNumber);
return data;
}
/**
* 处理合并单元格
*
* @param data 解析数据
* @param extraMergeInfoList 合并单元格信息
* @param headRowNumber 起始行
* @return 填充好的解析数据
*/
public List<T> explainMergeData(List<T> data, List<CellExtra> extraMergeInfoList, Integer headRowNumber) {
//循环所有合并单元格信息
extraMergeInfoList.forEach(cellExtra -> {
int firstRowIndex = cellExtra.getFirstRowIndex() - headRowNumber;
int lastRowIndex = cellExtra.getLastRowIndex() - headRowNumber;
int firstColumnIndex = cellExtra.getFirstColumnIndex();
int lastColumnIndex = cellExtra.getLastColumnIndex();
//获取初始值
Object initValue = getInitValueFromList(firstRowIndex, firstColumnIndex, data);
//设置值
for (int i = firstRowIndex; i <= lastRowIndex; i++) {
for (int j = firstColumnIndex; j <= lastColumnIndex; j++) {
setInitValueToList(initValue, i, j, data);
}
}
});
return data;
}
/**
* 设置合并单元格的值
*
* @param filedValue 值
* @param rowIndex 行
* @param columnIndex 列
* @param data 解析数据
*/
public void setInitValueToList(Object filedValue, Integer rowIndex, Integer columnIndex, List<T> data) {
T object = data.get(rowIndex);
for (Field field : object.getClass().getDeclaredFields()) {
//提升反射性能，关闭安全检查
field.setAccessible(true);
ExcelProperty annotation = field.getAnnotation(ExcelProperty.class);
if (annotation != null) {
if (annotation.index() == columnIndex) {
try {
field.set(object, filedValue);
break;
} catch (IllegalAccessException e) {
LOGGER.error("设置合并单元格的值异常："+e.getMessage());
}
}
}
}
}
/**
* 获取合并单元格的初始值
* rowIndex对应list的索引
* columnIndex对应实体内的字段
*
* @param firstRowIndex 起始行
* @param firstColumnIndex 起始列
* @param data 列数据
* @return 初始值
*/
private Object getInitValueFromList(Integer firstRowIndex, Integer firstColumnIndex, List<T> data) {
Object filedValue = null;
T object = data.get(firstRowIndex);
for (Field field : object.getClass().getDeclaredFields()) {
//提升反射性能，关闭安全检查
field.setAccessible(true);
ExcelProperty annotation = field.getAnnotation(ExcelProperty.class);
if (annotation != null) {
if (annotation.index() == firstColumnIndex) {
try {
filedValue = field.get(object);
break;
} catch (IllegalAccessException e) {
LOGGER.error("设置合并单元格的初始值异常："+e.getMessage());
}
}
}
}
return filedValue;
}
}
对数据进行处理：
List<UserExcelDto> data = new ExcelMergeHelper().explainMergeData(easyExcelListener.getData(), extraMergeInfoList, headRowNumber);
封装后的数据，这种数据，我们就可以进行业务处理，过程相对比较麻烦
[
{
"code": "510000",
"password": "********",
"name": "user1",
"addressName": "广州天河区",
"seq": "1"
},
{
"code": "510001",
"password": "********",
"name": "user1",
"addressName": "广州天河区",
"seq": "1"
},
{
"code": "510002",
"password": "***",
"name": "user2",
"addressName": "广州天河区",
"seq": "2"
}
]
package com.common.excel;
import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.metadata.CellExtra;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.lang.reflect.Field;
import java.util.List;
public class ExcelMergeHelper<T> {
private static final Logger LOGGER = LoggerFactory.getLogger(ExcelMergeHelper.class);
/**
* 处理合并单元格
*
* @param data 解析数据
* @param extraMergeInfoList 合并单元格信息
* @param headRowNumber 起始行
* @return 填充好的解析数据
*/
public List<T> explainMergeData(List<T> data, List<CellExtra> extraMergeInfoList, Integer headRowNumber) {
//循环所有合并单元格信息
extraMergeInfoList.forEach(cellExtra -> {
int firstRowIndex = cellExtra.getFirstRowIndex() - headRowNumber;
int lastRowIndex = cellExtra.getLastRowIndex() - headRowNumber;
int firstColumnIndex = cellExtra.getFirstColumnIndex();
int lastColumnIndex = cellExtra.getLastColumnIndex();
//获取初始值
Object initValue = getInitValueFromList(firstRowIndex, firstColumnIndex, data);
//设置值
for (int i = firstRowIndex; i <= lastRowIndex; i++) {
for (int j = firstColumnIndex; j <= lastColumnIndex; j++) {
setInitValueToList(initValue, i, j, data);
}
}
});
return data;
}
/**
* 设置合并单元格的值
*
* @param filedValue 值
* @param rowIndex 行
* @param columnIndex 列
* @param data 解析数据
*/
public void setInitValueToList(Object filedValue, Integer rowIndex, Integer columnIndex, List<T> data) {
if (!(data.size()>rowIndex))
return;
T object = data.get(rowIndex);
for (Field field : object.getClass().getDeclaredFields()) {
//提升反射性能，关闭安全检查
field.setAccessible(true);
ExcelProperty annotation = field.getAnnotation(ExcelProperty.class);
if (annotation != null) {
if (annotation.index() == columnIndex) {
try {
field.set(object, filedValue);
break;
} catch (IllegalAccessException e) {
LOGGER.error("设置合并单元格的值异常："+e.getMessage());
}
}
}
}
}
/**
* 获取合并单元格的初始值
* rowIndex对应list的索引
* columnIndex对应实体内的字段
*
* @param firstRowIndex 起始行
* @param firstColumnIndex 起始列
* @param data 列数据
* @return 初始值
*/
private Object getInitValueFromList(Integer firstRowIndex, Integer firstColumnIndex, List<T> data) {
Object filedValue = null;
T object = data.get(firstRowIndex);
for (Field field : object.getClass().getDeclaredFields()) {
//提升反射性能，关闭安全检查
field.setAccessible(true);
ExcelProperty annotation = field.getAnnotation(ExcelProperty.class);
if (annotation != null) {
if (annotation.index() == firstColumnIndex) {
try {
filedValue = field.get(object);
break;
} catch (IllegalAccessException e) {
LOGGER.error("设置合并单元格的初始值异常："+e.getMessage());
}
}
}
}
return filedValue;
}
}
本博客代码例子可以在GitHub找到下载链接
