easyExcel解析复杂表头数据
public class MdExcelListener<T> extends AnalysisEventListener<T> {
private static final Logger log = LoggerFactory.getLogger(MdExcelListener.class);
//表头所在行数
private int headRowNumber;
//开始读取行数，实际再+1
private int startRowNumber;
// Excel对象
private Class<T> clazzT;
public MdExcelListener() {
}
public MdExcelListener(int headRowNumber, int startRowNumber, Class<T> clazzT) {
this.headRowNumber = headRowNumber;
this.startRowNumber = startRowNumber;
this.clazzT = clazzT;
}
/**
* 每隔5条存储数据库，实际使用中可以100条，然后清理list ，方便内存回收
*/
private static final int BATCH_COUNT = 100;
/**
* 缓存的数据
*/
private List<T> cachedDataList = ListUtils.newArrayList();
@Override
public void invoke(T data, AnalysisContext context) {
if (context.readRowHolder().getRowIndex().intValue() > startRowNumber) {
//("解析到一条数据:{}", (data));
cachedDataList.add(data);
}
}
/**
* @param headMap 传入Excel的头部（第headRowNumber行数据）数据的index,name
* @param context
* @description: 校验Excel头部格式，必须完全匹配
* @date 2019/12/24 19:27
*/
private static int i=0;
@Override
public void invokeHeadMap(Map<Integer, String> headMap, AnalysisContext context) {
i++;
if (i == headRowNumber) {
super.invokeHeadMap(headMap, context);
validExcelHeader(headMap, clazzT);
}
}
@Override
public void doAfterAllAnalysed(AnalysisContext analysisContext) {
}
/**
* @param clazzT
* @return <, >
* @description: 获取注解里ExcelProperty的value，用作校验excel
* @date 2021/12/09 19:21
*/
public static <T> void validExcelHeader(Map<Integer, String> headMap, Class<T> clazzT) {
System.out.println("表头检验");
// 判断传入对象
if (Objects.isNull(clazzT)) {
return;
}
// 获取表头值
Collection<String> heads = headMap.values();
// 获取类注解的表头值
Set<String> nameMap = getNameSet(clazzT);
// 循环验证表头是否正确
for (String head : heads) {
if (!nameMap.contains(head)) {
throw new BizException("解析excel表头与模板不符，解析失败");
}
}
}
static <T> Set<String> getNameSet(Class<T> clazzT) {
Set<String> result = new HashSet<>();
Field[] fields = clazzT.getDeclaredFields();
for (Field field : fields) {
field.setAccessible(true);
ExcelProperty excelProperty = field.getAnnotation(ExcelProperty.class);
if (excelProperty != null) {
String[] values = excelProperty.value();
StringBuilder value = new StringBuilder();
for (String v : values) {
value.append(v);
}
result.add(value.toString());
}
}
return result;
}
public List<T> getCachedDataList() {
return cachedDataList;
}
}