四、代码清单1. 合并单元格只有第一个（firstRowIndex，firstColumnIndex）有值，所以要取到这个值。
2. 通过获取到的合并单元格信息（firstRowIndex,lastRowIndex,firstColumnIndex,lastColumnIndex），遍历此区域的每一个单元格，并给每一个单元格都赋上该值
3. 此方法的重点在于利用反射找到实体对应的属性，对应关系是@ExcelProperty(index = 0)
-> columnIndex
`index`对应了`columnIndex（也就是字段在excel所在的位置）`；`rowindex`对应了解析出来的`List<T> data的索引值`
1. UploadDataListener.java
import com.alibaba.excel.context.AnalysisContext;
import com.alibaba.excel.event.AnalysisEventListener;
import com.alibaba.excel.metadata.CellExtra;
import com.alibaba.fastjson.JSON;
import com.baomidou.mybatisplus.extension.api.Assert;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.ArrayList;
import java.util.List;
/**
* 模板的读取类
*
* @author wangwei
*/
public class UploadDataListener<T> extends AnalysisEventListener<T> {
private static final Logger LOGGER = LoggerFactory.getLogger(UploadDataListener.class);
/**
* 解析的数据
*/
List<T> list = new ArrayList<>();
/**
* 正文起始行
*/
private Integer headRowNumber;
/**
* 合并单元格
*/
private List<CellExtra> extraMergeInfoList = new ArrayList<>();
public UploadDataListener(Integer headRowNumber) {
this.headRowNumber = headRowNumber;
}
/**
* 这个每一条数据解析都会来调用
*
* @param data one row value. Is is same as {@link AnalysisContext#readRowHolder()}
* @param context context
*/
@Override
public void invoke(T data, AnalysisContext context) {
LOGGER.info("解析到一条数据:{}", JSON.toJSONString(data));
list.add(data);
}
/**
* 所有数据解析完成了 都会来调用
*
* @param context context
*/
@Override
public void doAfterAllAnalysed(AnalysisContext context) {
LOGGER.info("所有数据解析完成！");
}
/**
* 加上存储数据库
*/
public List<T> getData() {
return list;
}
@Override
public void extra(CellExtra extra, AnalysisContext context) {
LOGGER.info("读取到了一条额外信息:{}", JSON.toJSONString(extra));
switch (extra.getType()) {
case COMMENT: {
LOGGER.info("额外信息是批注,在rowIndex:{},columnIndex;{},内容是:{}", extra.getRowIndex(), extra.getColumnIndex(),
extra.getText());
break;
}
case HYPERLINK: {
if ("Sheet1!A1".equals(extra.getText())) {
LOGGER.info("额外信息是超链接,在rowIndex:{},columnIndex;{},内容是:{}", extra.getRowIndex(),
extra.getColumnIndex(), extra.getText());
} else if ("Sheet2!A1".equals(extra.getText())) {
LOGGER.info(
"额外信息是超链接,而且覆盖了一个区间,在firstRowIndex:{},firstColumnIndex;{},lastRowIndex:{},lastColumnIndex:{},"
"内容是:{}",
extra.getFirstRowIndex(), extra.getFirstColumnIndex(), extra.getLastRowIndex(),
extra.getLastColumnIndex(), extra.getText());
} else {
Assert.fail("Unknown hyperlink!");
}
break;
}
case MERGE: {
LOGGER.info(
"额外信息是合并单元格,而且覆盖了一个区间,在firstRowIndex:{},firstColumnIndex;{},lastRowIndex:{},lastColumnIndex:{}",
extra.getFirstRowIndex(), extra.getFirstColumnIndex(), extra.getLastRowIndex(),
extra.getLastColumnIndex());
if (extra.getRowIndex() >= headRowNumber) {
extraMergeInfoList.add(extra);
}
break;
}
default: {
}
}
}
public List<CellExtra> getExtraMergeInfoList() {
return extraMergeInfoList;
}
}
2. ExcelAnalysisHelper.java
import cn.xxx.UploadDataListener;
import cn.xxx.BizException;
import cn.xxx.ResultCode;
import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.Annotation.ExcelProperty;
import com.alibaba.excel.enums.CellExtraTypeEnum;
import com.alibaba.excel.metadata.CellExtra;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.CollectionUtils;
import org.springframework.web.multipart.MultipartFile;
import java.io.IOException;
import java.lang.reflect.Field;
import java.util.List;
/**
* @author wangwei
* @date 2020-12-01 13:34
**/
public class ExcelAnalysisHelper<T> {
private static final Logger LOGGER = LoggerFactory.getLogger(ExcelAnalysisHelper.class);
public List<T> getList(MultipartFile file, Class<T> clazz) {
return getList(file, clazz, 0, 1);
}
public List<T> getList(MultipartFile file, Class<T> clazz, Integer sheetNo, Integer headRowNumber) {
UploadDataListener<T> listener = new UploadDataListener<>(headRowNumber);
try {
EasyExcel.read(file.getInputStream(), clazz, listener).extraRead(CellExtraTypeEnum.MERGE).sheet(sheetNo).headRowNumber(headRowNumber).doRead();
} catch (IOException 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
*/
private 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) {
throw new BizException(ResultCode.FAILURE, "解析数据时发生异常!");
}
}
}
}
}
/**
* 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) {
throw new BizException(ResultCode.FAILURE, "解析数据时发生异常!");
}
}
}
}
return filedValue;
}
}
注：easyexcel版本为2.2.6**
<!--========================EasyExcel 配置============================-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>easyexcel</artifactId>
<version>2.2.6</version>
</dependency>
<!--========================EasyExcel 配置结束========================-->
