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How to set Page Breaks View Mode for .xls using hssfwork book ApachePOI

I am creating an .xls excel file using apache poi. I need to set the Page Breaks View by default. But I did look at a related question on .xlsx file . I didn't find anything "how to set Page Breaks View Mode" to using HSSF of ApachePOI
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The binary BIFF file system of *.xls and the Office Open XML file system of *.xlsx are two totally different file systems. You can't mix them. In apache poi HSSF ist for the one and XSSF for the other. The high level classes of apache poi try providing methods for both the file systems. This gets done using interfaces in SS. But outside the high level classes one needs strictly differentiate the both file systems.
Setting page break preview for a sheet is not provided by the high level classes up to now. So we need the underlyinf low lewel classes. For XSSF this are the org.openxmlformats.schemas.spreadsheetml.x2006.main.* classes, which are the XML representation of the XSSF internals. But for HSSF this are the org.apache.poi.hssf.record.* classes, which are the binary representation of the HSSF internals.
Setting page break preview for a sheet could be done like so for both the file systems:
import java.io.*;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.*;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.hssf.model.InternalSheet;
import org.apache.poi.hssf.record.WindowTwoRecord;
public class ExcelPageBreakPreview {
public static void main(String[] args) throws Exception {
//Workbook workbook = WorkbookFactory.create(new FileInputStream("./ExcelTemplate.xlsx")); String filePath = "./ExcelInPageBreakPreview.xlsx";
Workbook workbook = WorkbookFactory.create(new FileInputStream("./ExcelTemplate.xls")); String filePath = "./ExcelInPageBreakPreview.xls";
Sheet sheet = workbook.getSheetAt(0);
//set sheet in PageBreakPreview
if (sheet instanceof XSSFSheet) {
XSSFSheet xssfSheet= (XSSFSheet)sheet;
xssfSheet.lockSelectLockedCells(true);
xssfSheet.getCTWorksheet().getSheetViews().getSheetViewArray(0).setView(org.openxmlformats.schemas.spreadsheetml.x2006.main.STSheetViewType.PAGE_BREAK_PREVIEW);
} else if (sheet instanceof HSSFSheet) {
HSSFSheet hssfSheet= (HSSFSheet)sheet;
InternalSheet internalSheet = hssfSheet.getSheet();
WindowTwoRecord record = internalSheet.getWindowTwo();
record.setSavedInPageBreakPreview(true);
}
FileOutputStream fileOut = new FileOutputStream(filePath);
workbook.write(fileOut);
fileOut.close();
workbook.close();
}
}
Previous apache poi versions might not have InternalSheet HSSFSheet.getSheet public. Then one needs using reflection to get the InternalSheet:
//InternalSheet internalSheet = hssfSheet.getSheet();
java.lang.reflect.Field _sheet = HSSFSheet.class.getDeclaredField("_sheet");
_sheet.setAccessible(true);
InternalSheet internalSheet = (InternalSheet)_sheet.get(hssfSheet);

How to make verticaltext cellstyle with Apache POI?

Recently, I met a question:
I need to export an excel(xlsx) with java, which must contain this kind of cell style:
I made a excel file with this vertical text, and exported as a xml file. Then I found that the style has an attribute named 'VerticalText':
By experience, I chose Apache POI. But I couldn't find any way to generate the cell style with POI. I could only find rotate method, which could't meet the requirement.
So I read more code of POI, and found that the cellstyles are build from some xsb file, which do not contain vertical text either.
Any help much appreciated.

The XML in your picture is Excel 2003 SpreadsheetML. But an *.xlsx file is a ZIP archive containing Office Open XML files. In that ZIP archive the styles.xml contains:
...
<cellXfs count="2">
...
<xf numFmtId="0" fontId="0" fillId="0" borderId="0" xfId="0">
<alignment textRotation="255"/>
</xf>
</cellXfs>
...
There <alignment textRotation="255"/> is for vertical text.
This can be set using apache poi like so:
import java.io.FileOutputStream;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
public class CreateXSSFVerticalText {
public static void main(String[] args) throws Exception {
Workbook workbook = new XSSFWorkbook();
CellStyle cellStyle = workbook.createCellStyle();
cellStyle.setRotation((short)255);
Sheet sheet = workbook.createSheet();
Row row = sheet.createRow(0);
Cell cell = row.createCell(0);
cell.setCellValue("test");
cell.setCellStyle(cellStyle);
FileOutputStream fileOut = new FileOutputStream("CreateXSSFVerticalText.xlsx");
workbook.write(fileOut);
fileOut.close();
workbook.close();
}
}
Since the Office Open XML formats (like *.xlsx) are ZIP archives containing XML files it is pretty easy to determine the necessary XML attributes. Simply create a simple *.xlsx file having the needed formatting using the Excel GUI. Then unzip the *.xlsx file and have a look at xl/styles.xml.

Invalid Header Signature

Here I want to extract the data from .xlsx file and for that I already add the poi jar and created the reference of fileInputStream
package demo;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
public class DemoExcel {
public static void main(String[] args) throws Exception{
File excel = new File("C:\\Users\\Devaditya\\Documents\\Book1.xlsx");
FileInputStream fis = null;
fis = new FileInputStream(excel);
System.out.println(fis.toString());
HSSFWorkbook wb = new HSSFWorkbook(fis);
System.out.println(wb.toString());
HSSFSheet sh = wb.getSheet("Data");
System.out.println(sh.toString());
}
}
Here i am getting the error:-
Exception in thread "main" java.io.IOException: Invalid header signature; read 0, expected -2226271756974174256
at org.apache.poi.poifs.storage.HeaderBlockReader.<init>(HeaderBlockReader.java:88)
at org.apache.poi.poifs.filesystem.POIFSFileSystem.<init>(POIFSFileSystem.java:83)
at org.apache.poi.hssf.usermodel.HSSFWorkbook.<init>(HSSFWorkbook.java:210)
at org.apache.poi.hssf.usermodel.HSSFWorkbook.<init>(HSSFWorkbook.java:191)
at demo.DemoExcel.main(DemoExcel.java:23)

Lets start with types of WorkBook.
HSSFWorkbook
This is old binary proprietary Excel format, know by the extension .xls.
XSSFWorkbook
This is the new XML Excel format, known by the extension .xlsx.
So, you are using the wrong class.
In fact it would be better not to use a specific class at all, let POI work out what you have. Use a WorkbookFactory:
final Workbook workbook = WorkbookFactory.create(excel);
This is:
programming to the interface.
robust to changes in the type of workbook read, as long a POI supports it
faster and more efficient. POI can read the File piecemeal, when it needs to rather than having to slurp the whole workbook into memory.
Doesn't have the memory leak that you have when you don't close() the FileInputStream.

try to open the file in microsoft office Excel then a pop message will appear to inform you that that file you are trying to open isn't an excel file, and give you the choice to open it any way, so just open it and save it as excel file.

POI is not recognised

Im using struts application. I want to work on reports. So going to try POI. I got this jar file poi-3.6-20091214.jar and put them in web-inf/lib folder.When i try using them in class file poi is not recognised. Im trying below...
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook; //..
HSSFWorkbook workbook = new HSSFWorkbook();
HSSFSheet sheet = workbook.createSheet("Sample sheet"); //Create a new row in current sheet
Row row = sheet.createRow(0); //Create a new cell in current row
Cell cell = row.createCell(0); //Set value to new value
cell.setCellValue("Blahblah");
But import itself wouldnt work.Any idea?

Have you added into the eclipse lib path?
another thing: use poi 3.8, is more recent. Why start with an old release?

I think its HSSFRow & HSSFCell and not Row and Cell. These are included in the jar.
One point to consider using POI is that the same code will not be able to handle both .xls and .xlsx file formats.
missed this: it will be XSSF if you are using .xlsx files and HSSF for .xls file format.

Handling Excel file in Java

I have a Excel file that I have to read the file and go line by line and check the first column. Here is an example of the column headers
ISBN#13 Run Date Title Author Type
So I have to check each ISBN#13 and determine if it is an isbn#13, format it and write the whole line to a file. Then take all the ones that are not ISBN#13 and write them to a file.
So the question is how do I check the column "ISBN#13" and how do I write each row to a file. It would be another excel file.

There is also xslx4j (part of docx4j) if you are working with xlsx only (ie not the legacy binary .xls) and prefer to use jaxb

The Apache poi (Poor Obfuscation Implementation) project is made for reading from and writing to Excel files in Java:
http://poi.apache.org/
Code example:
import java.io.*;
import org.apache.poi.xssf.usermodel.*;
public class CreateWorkBook
{
public static void main(String[] args)throws Exception
{
//Create Blank workbook
XSSFWorkbook workbook = new XSSFWorkbook();
//Create file system using specific name
FileOutputStream out = new FileOutputStream(
new File("createworkbook.xlsx"));
//write operation workbook using file out object
workbook.write(out);
out.close();
System.out.println("createworkbook.xlsx written successfully");
}
}