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Copying mutiple Excel sheets of different workbook into a single workbook

Problem: How to copy multiple Excel sheets of different workbook into a single workbook not by cell by cell copying as it makes performance issues as I have large data in sheets.Is there any option to copy whole sheets without iterating over every cell using Java. Just copy the whole sheets into other.

This below will copy every worksheet from a workbook you set. I will copy it and paste it at the end of the list of sheets on your current workbook
Sub CopyWorkbook()
Dim sh as Worksheet, wb as workbook
Set wb = workbooks("Target workbook")
For Each sh in workbooks("source workbook").Worksheets
sh.Copy After:=wb.Sheets(wb.sheets.count)
Next sh
End Sub

How to read super large excel file using java

I have an excel file with over 1 million rows (about 60 MB) and I want to read them using java , I have the following code to read :
FileInputStream file = new FileInputStream(
new File(
"path/file.xlsx"));
XSSFWorkbook workbook = new XSSFWorkbook(file);
XSSFSheet sheet = workbook.getSheetAt(0);
at creating workbook line it takes forever I tried it on small files it work perfectly but with this file it takes more than an hour and nothing !
what is the best way to read file like this ?

apache poi copy from very large xls to new workbook sheet

I have very large xls file , which contains two sheets. I want to combine these two sheets into one and copy to new workbook . But I get out of memory exception when I try to access this large xls as below :
FileInputStream fis = new FileInputStream(new File("input.xls"));
HSSFWorkbook workbook = new HSSFWorkbook(fis);
I tried using event api for xls : http://poi.apache.org/spreadsheet/how-to.html#event_api
But using that we can only read the cell values . But here I need to copy to new excel sheet.

Apache POI provides a low-memory footprint SXSSF API to write data to xlsx. It does not load everything in memory at once so it's the solution while working with very large excel files. You may want to consider this.

Fetch data from Excel file having merged cells and store in MySQL database

I have an Excel file of normal cells along with merged cells and a task to store each row in the Excel file to MySQL database. I am able to get data of each cell from Excel file and store in the database except data from merged cells. My java code:
FileInputStream input = new FileInputStream("/Users/test.xlsx");
Workbook wb = WorkbookFactory.create(input);
Sheet sheet = wb.getSheetAt(0);
for(i=0;i<no.ofrows;i++)
for(j=0;j<no.ofcolomns;j++)
{
String var = String.valueOf(sheet.getRow(i).getCell(j));
}

You may want to check Sheet#getMergedRegions() and Sheet#getMergedRegion(int index) JavaDoc.

Check out this link; HOW TO READ A NEW EXCEL SHEET for a tutorial to read excel xlsx files.

Unable to read excel files in java getting 2 below error in java

I am trying to read xls and xlsx files with below code and get data from it but i am able to read 70% of xl files i am having but for some i am getting below errors
for remaining files some are giving 1st error and some are giving 2nd error
1)java.lang.IllegalArgumentException: The supplied POIFSFileSystem does not contain a BIFF8 'Workbook' entry. Is it really an excel file?
2)java.lang.IllegalArgumentException: Your InputStream was neither an OLE2 stream, nor an OOXML stream
Both above errors are coming for xlsx extension files
Why am i able to read some and not some files and is there any global solution to this
My java code:
FileInputStream input = new FileInputStream("/Users/Xl_Files/"+fileName);
Workbook wb = WorkbookFactory.create(input);
Sheet sheet = wb.getSheetAt(0);
String var = String.valueOf(sheet.getRow(Row).getCell(Colon));