[Java123] POI CellType data type

Today to do a conversion process for Excel instead POI API from JXL API.

Conversion process found that many details need to be able to process.

POI CellType only supports the following types:

CellType type value
CELL_TYPE_NUMERIC numeric 0
CELL_TYPE_STRING string. 1
CELL_TYPE_FORMULA Formula Type 2
CELL_TYPE_BLANK null. 3
CELL_TYPE_BOOLEAN Boolean. 4
CELL_TYPE_ERROR error 5

Does not support date Date type: https://www.cnblogs.com/acm-bingzi/p/6674834.html

Comparative JXL Cell Type: https://www.cnblogs.com/aigeileshei/p/5578086.html