回收信件

 Android SQL

https://blog.tarswork.com/post/android-storage-using-sqlite/

Android Excel read

https://blog.csdn.net/u010198148/article/details/65044639

https://medium.com/geekculture/creating-an-excel-in-android-cd9c22198619

buildscript {
       repositories {
        google()
        mavenCentral()
    }
...
}

implementation 'org.apache.poi:poi:5.2.2'
implementation 'org.apache.poi:poi-ooxml:5.2.2'

excel bug fix

import org.apache.poi.ss.usermodel.DataFormatter;

FileInputStream fis = new FileInputStream(workbookName);
Workbook workbook = WorkbookFactory.create(fis);
Sheet sheet = workbook.getSheet(sheetName);
DataFormatter formatter = new DataFormatter();
String val = formatter.formatCellValue(sheet.getRow(row).getCell(col));
list.add(val);   //Adding value to list