导出数据，支持List<Map>数据导出。

[3398502339]

有一个业务场景，导入数据的时候，如果类型转换异常了，我们需要把转换错误的数据保存下来，并写到excel返回给客户看到底是那个字段的数据有问题，这个时候，失败了的数据，可能就会用到map,jsonobject等，目前发现写到excel中，
public class FileWriteStream {
public static final String errorReason = "导入失败原因";
public final File file;
private final ExcelWriter excelWriter;
private boolean isClosed = false;
private int recordCount = 0;
private final int maxRecords;

public <T> FileWriteStream(Class<T> dtoClass, File file, int maxRecords) throws IOException {
    this.file = file;
    this.excelWriter = FastExcel.write(file).head(getHead(dtoClass)).build();
    this.maxRecords = maxRecords;
}

public void write(Map<String,Object> data) throws IOException {
    if (isClosed || excelWriter == null) {
        throw new RuntimeException("文件流已关闭，无法继续写入");
    }
    WriteSheet sheet = FastExcel.writerSheet("Sheet1").build();
    excelWriter.write(Collections.singletonList(data), sheet);
    recordCount++;
}

public boolean isFull() {
    return recordCount >= maxRecords;
}

public void close() throws IOException {
    if (excelWriter != null && !isClosed) {
        try {
            excelWriter.finish();
            isClosed = true;
        } catch (Exception e) {
            throw new RuntimeException("关闭 ExcelWriter 失败", e);
        }
    }
}

public static  <T> List<List<String>> getHead(Class<T> clazz) {
    Field[] fields = clazz.getDeclaredFields();
    List<List<String>> list = Arrays.stream(fields)
            .map(f -> {
                ExcelProperty annotation = f.getAnnotation(ExcelProperty.class);
                return annotation != null ? Arrays.asList(annotation.value()) : Collections.singletonList(f.getName());
            })
            .collect(Collectors.toList());
    list.addAll(Collections.singleton(Arrays.asList(errorReason)));
    return list;
}

}

这是测试写入的代码，可以参考一下，
/**
* 错误文件写入
* @param errorData
*/
private void writeErrorToFile(Map<String,Object> errorData) {
try {
if (importContext.currentFileStream == null || importContext.currentFileStream.isFull()) {
if (importContext.currentFileStream != null) {
importContext.currentFileStream.close();
if (importContext.currentFileStream.file != null) {
importContext.tempErrorFiles.add(importContext.currentFileStream.file);
}
}
File newTempFile = File.createTempFile("error_", ".xlsx");
importContext.currentFileStream = new FileWriteStream(importContext.handler.getDTOClass(),newTempFile, importContext.maxRecordsPerFile);
}
importContext.currentFileStream.write(errorData);
} catch (Exception e) {
log.error("写入错误记录到临时文件失败", e);
}
}

[delei]

Can you describe the problem or error message in detail?

• When importing data, if you need to handle validation errors, you can handle the collected error messages in a custom ReadListener using the onException or doAfterAllAnalysed methods,generate a new file containing the error messages.
• By the way ,in the submitted PR Added validation functionality when reading files, generating error messages based on validation results. Supports manually adding error messages #282 , an implementation approach is also provided.

Please refer to this and see if it is helpful to you.

能否具体描述下发现的问题或错误信息?

• 导入数据时，如果验证数据错误信息，可以在自定义的ReadListener中，将收集到的错误信息通过onException或doAfterAllAnalysed方法处理，生成一个新的包含错误信息的新文件。
• 在已提交的 PR-282 中，也提供了一种实现思路。

请参考以上建议看是否对你有所帮助

[3398502339]

我是在这里处理的

[3398502339]

这个问题我知道，跟源码才知道，参数传错了，你这个可以Map导出