[alibaba/easyexcel]当类的属性没有按照ExcelProperty的属性index顺序排序的时候，写数据出现错乱

触发场景描述 当类的属性没有按照ExcelProperty注解的属性index排序的时候，写数据出现错乱顺序 触发Bug的代码

   public class EasyExcelFound {

    /**
     * 写数据
     */
    @Test
    public void indexNotSort() {
        Path path = Paths.get("/home/liuxu/Public/not-sort.xlsx");
        ExcelWriter excelWriter = EasyExcel.write(path.toFile())
                .build();
        WriteSheet writeSheet = EasyExcel.writerSheet("出现不排序的情况")
                .head(head())
                .build();

        excelWriter.write(data(),writeSheet);
        excelWriter.finish();
    }

    private List<List<String>> head() {
        List<List<String>> head = new ArrayList<>();
        head.add(Collections.singletonList("名字"));
        head.add(Collections.singletonList("ID编号"));
        return head;
    }

    public List<CluesDto> data() {
        return IntStream.rangeClosed(0, 3)
                .boxed()
                .map(integer -> {
                    CluesDto cluesDto = new CluesDto();
                    cluesDto.setId(integer);
                    cluesDto.setName("线索名字-" + integer);
                    cluesDto.setCreateDate(new Date());
                    return cluesDto;
                })
                .collect(Collectors.toList());
    }
}

@ExcelIgnoreUnannotated
class CluesDto {
    @ExcelProperty(index = 1)
    private Integer id;

    @ExcelProperty(index = 0)
    private String name;

    private Date createDate;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Date getCreateDate() {
        return createDate;
    }

    public void setCreateDate(Date createDate) {
        this.createDate = createDate;
    }
}

提示的异常或者没有达到的效果 写入结果为:

可以看到excel中的：名字和ID编号两列写反了。

目前的解决方案：在CluesDto类中，把id,name属性按照index的增长顺序写就行，也就是调整为:

@ExcelIgnoreUnannotated
class CluesDto {
    @ExcelProperty(index = 0)
    private String name;

    @ExcelProperty(index = 1)
    private Integer id;

    private Date createDate;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Date getCreateDate() {
        return createDate;
    }

    public void setCreateDate(Date createDate) {
        this.createDate = createDate;
    }
}

跟踪了下源码，发现： com.alibaba.excel.util.ClassUtils类中获取declaredFields的方法，获取allFieldList没有按照ExcelProperty的index进行排序。导致后面写入数据的时候获取fieldList只是按照反射拿取的字段顺序为准，并没有按照index排序。