Develop Reference

Getting weird string value from excel using Apache POI in Java [duplicate]

I am using Apache POI API to getting values from an Excel file.
Everything is working great except with cells containing formulas. In fact, the cell.getStringCellValue() is returning the formula used in the cell and not the value of the cell.
I tried to use evaluateFormulaCell() method but it's not working because I am using GETPIVOTDATA Excel formula and this formula is not implemented in the API:
Exception in thread "main" org.apache.poi.ss.formula.eval.NotImplementedException: Error evaluating cell Landscape!K11
at org.apache.poi.ss.formula.WorkbookEvaluator.addExceptionInfo(WorkbookEvaluator.java:321)
at org.apache.poi.ss.formula.WorkbookEvaluator.evaluateAny(WorkbookEvaluator.java:288)
at org.apache.poi.ss.formula.WorkbookEvaluator.evaluate(WorkbookEvaluator.java:221)
at org.apache.poi.hssf.usermodel.HSSFFormulaEvaluator.evaluateFormulaCellValue(HSSFFormulaEvaluator.java:320)
at org.apache.poi.hssf.usermodel.HSSFFormulaEvaluator.evaluateFormulaCell(HSSFFormulaEvaluator.java:213)
at fromExcelToJava.ExcelSheetReader.unAutreTest(ExcelSheetReader.java:193)
at fromExcelToJava.ExcelSheetReader.main(ExcelSheetReader.java:224)
Caused by: org.apache.poi.ss.formula.eval.NotImplementedException: GETPIVOTDATA
at org.apache.poi.hssf.record.formula.functions.NotImplementedFunction.evaluate(NotImplementedFunction.java:42)

For formula cells, excel stores two things. One is the Formula itself, the other is the "cached" value (the last value that the forumla was evaluated as)
If you want to get the last cached value (which may no longer be correct, but as long as Excel saved the file and you haven't changed it it should be), you'll want something like:
for(Cell cell : row) {
if(cell.getCellType() == Cell.CELL_TYPE_FORMULA) {
System.out.println("Formula is " + cell.getCellFormula());
switch(cell.getCachedFormulaResultType()) {
case Cell.CELL_TYPE_NUMERIC:
System.out.println("Last evaluated as: " + cell.getNumericCellValue());
break;
case Cell.CELL_TYPE_STRING:
System.out.println("Last evaluated as \"" + cell.getRichStringCellValue() + "\"");
break;
}
}
}

Previously posted solutions did not work for me. cell.getRawValue() returned the same formula as stated in the cell. The following function worked for me:
public void readFormula() throws IOException {
FileInputStream fis = new FileInputStream("Path of your file");
Workbook wb = new XSSFWorkbook(fis);
Sheet sheet = wb.getSheetAt(0);
FormulaEvaluator evaluator = wb.getCreationHelper().createFormulaEvaluator();
CellReference cellReference = new CellReference("C2"); // pass the cell which contains the formula
Row row = sheet.getRow(cellReference.getRow());
Cell cell = row.getCell(cellReference.getCol());
CellValue cellValue = evaluator.evaluate(cell);
switch (cellValue.getCellType()) {
case Cell.CELL_TYPE_BOOLEAN:
System.out.println(cellValue.getBooleanValue());
break;
case Cell.CELL_TYPE_NUMERIC:
System.out.println(cellValue.getNumberValue());
break;
case Cell.CELL_TYPE_STRING:
System.out.println(cellValue.getStringValue());
break;
case Cell.CELL_TYPE_BLANK:
break;
case Cell.CELL_TYPE_ERROR:
break;
// CELL_TYPE_FORMULA will never happen
case Cell.CELL_TYPE_FORMULA:
break;
}
}

There is an alternative command where you can get the raw value of a cell where formula is put on. It's returns type is String. Use:
cell.getRawValue();

If the need is to read values from Excel sheets and having them as strings then, for example to present them somewhere or to use them in text file formats, then using DataFormatter will be the best.
DataFormatter is able to get a string from each cell value, whether the cell value itself is string, boolean, number, error or date. This string then looks the same as Excel will show it in the cells in it's GUI.
Only problem are formula cells. Up to apache poi 5.1.0 a FormulaEvaluator is needed to evaluate the formulas while using DataFormatter. This fails when apache poi is not able evaluating the formula. From 5.2.0 on the DataFormatter can be set to use cached values for formula cells. Then no formula evaluation is needed if Excel had evaluated the formulas before.
Complete example:
import org.apache.poi.ss.usermodel.*;
import java.io.FileInputStream;
class ReadExcel {
public static void main(String[] args) throws Exception {
Workbook workbook = WorkbookFactory.create(new FileInputStream("./ExcelExample.xlsx"));
// up to apache poi 5.1.0 a FormulaEvaluator is needed to evaluate the formulas while using DataFormatter
FormulaEvaluator evaluator = workbook.getCreationHelper().createFormulaEvaluator();
DataFormatter dataFormatter = new DataFormatter(new java.util.Locale("en", "US"));
// from 5.2.0 on the DataFormatter can set to use cached values for formula cells
dataFormatter.setUseCachedValuesForFormulaCells(true);
Sheet sheet = workbook.getSheetAt(0);
for (Row row : sheet) {
for (Cell cell : row) {
//String value = dataFormatter.formatCellValue(cell, evaluator); // up to apache poi 5.1.0
String value = dataFormatter.formatCellValue(cell); // from apache poi 5.2.0 on
System.out.println(value);
}
}
workbook.close();
}
}

If you want to extract a raw-ish value from a HSSF cell, you can use something like this code fragment:
CellBase base = (CellBase) cell;
CellType cellType = cell.getCellType();
base.setCellType(CellType.STRING);
String result = cell.getStringCellValue();
base.setCellType(cellType);
At least for strings that are completely composed of digits (and automatically converted to numbers by Excel), this returns the original string (e.g. "12345") instead of a fractional value (e.g. "12345.0"). Note that setCellType is available in interface Cell(as of v. 4.1) but deprecated and announced to be eliminated in v 5.x, whereas this method is still available in class CellBase. Obviously, it would be nicer either to have getRawValue in the Cell interface or at least to be able use getStringCellValue on non STRING cell types. Unfortunately, all replacements of setCellType mentioned in the description won't cover this use case (maybe a member of the POI dev team reads this answer).

SelThroughJava's answer was very helpful I had to modify a bit to my code to be worked .
I used https://mvnrepository.com/artifact/org.apache.poi/poi and https://mvnrepository.com/artifact/org.testng/testng as dependencies .
Full code is given below with exact imports.
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.util.CellReference;
import org.apache.poi.sl.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellType;
import org.apache.poi.ss.usermodel.CellValue;
import org.apache.poi.ss.usermodel.FormulaEvaluator;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.usermodel.WorkbookFactory;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
public class ReadExcelFormulaValue {
private static final CellType NUMERIC = null;
public static void main(String[] args) {
try {
readFormula();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void readFormula() throws IOException {
FileInputStream fis = new FileInputStream("C:eclipse-workspace\\sam-webdbriver-diaries\\resources\\tUser_WS.xls");
org.apache.poi.ss.usermodel.Workbook workbook = WorkbookFactory.create(fis);
org.apache.poi.ss.usermodel.Sheet sheet = workbook.getSheetAt(0);
FormulaEvaluator evaluator = workbook.getCreationHelper().createFormulaEvaluator();
CellReference cellReference = new CellReference("G2"); // pass the cell which contains the formula
Row row = sheet.getRow(cellReference.getRow());
Cell cell = row.getCell(cellReference.getCol());
CellValue cellValue = evaluator.evaluate(cell);
System.out.println("Cell type month is "+cellValue.getCellTypeEnum());
System.out.println("getNumberValue month is "+cellValue.getNumberValue());
// System.out.println("getStringValue "+cellValue.getStringValue());
cellReference = new CellReference("H2"); // pass the cell which contains the formula
row = sheet.getRow(cellReference.getRow());
cell = row.getCell(cellReference.getCol());
cellValue = evaluator.evaluate(cell);
System.out.println("getNumberValue DAY is "+cellValue.getNumberValue());
}
}

Apache POI cell type error

I am trying to use Apache POI to read an excel file that will have two columns: title and language. Title will have some sentences in a language, language column will be empty. After the Apache POI reads the sentence in the title, it should save it in a variable and then call the language-detect library (https://code.google.com/archive/p/language-detection/). I am especially having an error with the line where there is the case statement
import java.util.ArrayList;
import com.cybozu.labs.langdetect.Detector;
import com.cybozu.labs.langdetect.DetectorFactory;
import com.cybozu.labs.langdetect.Language;
import java.util.Scanner;
import com.cybozu.labs.langdetect.LangDetectException;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.Iterator;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
public class LangDetectSample {
public static void main(String[] args) throws IOException, LangDetectException {
String excelFilePath = "C:\\LD\\Books.xlsx";
FileInputStream inputStream = new FileInputStream(new File(excelFilePath));
Workbook workbook = new XSSFWorkbook(inputStream);
Sheet firstSheet = workbook.getSheetAt(0); // Assuming that the data is sheet in one
Iterator<Row> iterator = firstSheet.iterator();
DataFormatter formatter = new DataFormatter();
LangDetectSample lang = new LangDetectSample();
//creating variables
String title;
String language;
int rowNumber;
//Blank workbook
XSSFWorkbook wb = new XSSFWorkbook(); //new workbook //fixed
//Create a blank sheet
Sheet sheet1 = wb.createSheet("Predicted language"); //fixed
while (iterator.hasNext())
{
Row nextRow = iterator.next();
rowNumber = nextRow.getRowNum();
Cell cell = nextRow.getCell(2); // title is in column 2
switch (cell.getCellType()) {
case Cell.CELL_TYPE_STRING:
title = cell.getStringCellValue();
break;
case Cell.CELL_TYPE_BOOLEAN:
title = formatter.formatCellValue(cell);
break;
case Cell.CELL_TYPE_NUMERIC:
title = formatter.formatCellValue(cell);
break;
}
System.out.print(title);
//Title should now have the title.
// Call the language detector:
language = lang.detect(title);
System.out.println(lang);
// if language detected, attempt to output the result to the new excel file with the following commands:
// Write the title, language
Row row = sheet1.createRow(rowNumber); //changed var
Cell cell2 = row.createCell(2); //changed variable name
cell.setCellValue(title);
Cell cell3 = row.createCell(3);
cell.setCellValue(language);
}
try {
//Write the workbook in file system
FileOutputStream out = new FileOutputStream(new File("title-language.xlsx"));
workbook.write(out);
out.close();
} catch (Exception e)
{
e.printStackTrace();
}
workbook.close();
inputStream.close();
}
public void init(String profileDirectory) throws LangDetectException {
DetectorFactory.loadProfile(profileDirectory);
}
public String detect(String text) throws LangDetectException {
DetectorFactory.loadProfile("C:\\LD\\profiles");
Detector detector = DetectorFactory.create();
detector.append(text);
return detector.detect();
}
public ArrayList detectLangs(String text) throws LangDetectException {
Detector detector = DetectorFactory.create();
detector.append(text);
return detector.getProbabilities();
}
}
The error I am getting is
variable title may not have been initialised

for your first error of checking boolean, keep the vaiable of "Object" class e.g
Object title;
switch (cell.getCellType()) {
case Cell.CELL_TYPE_BOOLEAN:
title = cell.getBooleanCellValue();
break;
}
for your second error , java reads the cell value default in "double "
data type format , so you need to convert it to text/ String using following method...
Object title="";
title = new DecimalFormat("0").format(Cell.getNumericCellValue());
hope this will help you...
thanks

I think you have problems in cases
now in later version poi 4.0.1 CELL_TYPE_NUMERIC is now just NUMERIC remove CELL_TYPE_
switch (cell.getCellType()) {
case STRING:
title = cell.getStringCellValue();
break;
case BOOLEAN:
title = formatter.formatCellValue(cell);
break;
case NUMERIC:
title = formatter.formatCellValue(cell);
break;
}

XLSX to CSV out of memory error

I found plenty of solutions how to convert XLSX to CSV file using Java, all the solutions use: XSSFWorkbook. Problem I am facing is that probably the stream is having too much data. I just don't get why, the file is just 4mb.
CODE:
// For storing data into CSV files
StringBuffer data = new StringBuffer();
try {
FileOutputStream fos = new FileOutputStream(outputFile);
System.out.println("Getting input stream.");
// Get the workbook object for XLS file
XSSFWorkbook workbook = new XSSFWorkbook(new FileInputStream(inputFile));
System.out.println(" - Done");
// Get first sheet from the workbook
XSSFSheet sheet = workbook.getSheetAt(0);
Cell cell;
Row row;
// Iterate through each rows from first sheet
Iterator<Row> rowIterator = sheet.iterator();
System.out.println(" - Reading xlsx rows.");
while (rowIterator.hasNext()) {
i++;
row = rowIterator.next();
// For each row, iterate through each columns
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
cell = cellIterator.next();
switch (cell.getCellType()) {
case Cell.CELL_TYPE_BOOLEAN:
data.append(cell.getBooleanCellValue() + ";");
break;
case Cell.CELL_TYPE_NUMERIC:
data.append(cell.getNumericCellValue() + ";");
break;
case Cell.CELL_TYPE_STRING:
data.append(cell.getStringCellValue() + ";");
break;
case Cell.CELL_TYPE_BLANK:
data.append("" + ";");
break;
default:
data.append(cell + ";");
}
}
data.append('\n');
int limit = 10000;
if ((i % limit) == 0) {
System.out.println(" - Writing " + limit + " data.");
fos.write(data.toString().getBytes());
fos.flush();
data = null;
data = new StringBuffer();
System.out.println(" - Data written.");
}
}
fos.write(data.toString().getBytes());
fos.flush();
fos.close();
The error is pointing to line in switch statement where I am appending something to data (StringBuffer), but I am nulling it so it shouldn't be an issue.

Now you may not be able to use SXSSFWorkbook (as it's write-only), but you may be able to convert your program to streaming-style using the SAX-based API. Edit: Another thing you may want to try is to create the XSSFWorkbook from File instead of InputStream (I remember reading somewhere that the File-based code needs less memory).
(First try was:
Since you are reading data sequentially the SXSSFWorkbook class should be just the thing you need.)

The xlsx format is just a zip with content xml and shared-strings xml. Hence 4 MB compressed, may well be very large uncompressed.
Using a zip file system you could load the shared strings into memory, and then read content xml sequentially, immediately outputting.
As two inner files are concerned, you might use java's zip file system. Tedious but not difficult.

try this code this one is perfectly working for me i hope that also working for you.
package com.converting;
import java.io.FileInputStream;
import java.io.*;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import com.opencsv.CSVWriter;
import java.util.Iterator;
import java.io.FileWriter;
public class XlsxtoCSV {
public static void main(String[] args) throws Exception{
FileInputStream input_document = new FileInputStream(new File("/home/blackpearl/Downloads/aa.xlsx"));
XSSFWorkbook my_xls_workbook = new XSSFWorkbook(input_document);
XSSFSheet my_worksheet = my_xls_workbook.getSheetAt(0);
Iterator<Row> rowIterator = my_worksheet.iterator();
FileWriter my_csv=new FileWriter("/home/blackpearl/Downloads/Newaa.csv");
CSVWriter my_csv_output=new CSVWriter(my_csv);
while(rowIterator.hasNext()) {
Row row = rowIterator.next();
int i=0;//String array
String[] csvdata = new String[20];
Iterator<Cell> cellIterator = row.cellIterator();
while(cellIterator.hasNext()) {
Cell cell = cellIterator.next(); //Fetch CELL
switch(cell.getCellType()) { //Identify CELL type
case Cell.CELL_TYPE_STRING:
csvdata[i]= cell.getStringCellValue();
break;
}
i=i+1;
}
my_csv_output.writeNext(csvdata);
}
System.out.println("file imported");
my_csv_output.close(); //close the CSV file
input_document.close(); //close xlsx file
}
}

how to read excel file and insert those data into database using java and poi or any other libraray?

i am using servlet and trying to read the user uploaded excel file and insert into database.
my excel is in this format:
ID IP1 IP2 USER TKTNO(these are headings in excel & database table as well)
under those heading i have data in excel file which i have to read and insert into database.
please desperately need help....thank you

I am using Docx4J for this purpose... good with Docx and xlsx
http://www.docx4java.org/trac/docx4j

this is how you read an excel file using apache POI library , i guess this is good enough for starters , now you can take the cell values stored in some collection objects and store the object to Database according to requirement
package com.Excel;
import java.io.*;
import java.util.Iterator;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
public class ReadExcelFile {
public static void main(String[] args)
{
try {
FileInputStream file = new FileInputStream(new File("C:/Users/hussain.a/Desktop/mar_25/Tradestation_Q4 Dashboard_Week 5_1029-1104.xlsx"));
XSSFWorkbook workbook = new XSSFWorkbook(file);
XSSFSheet sheet = workbook.getSheetAt(0);
Iterator<Row> rowIterator = sheet.iterator();
rowIterator.next();
while(rowIterator.hasNext())
{
Row row = rowIterator.next();
//For each row, iterate through each columns
Iterator<Cell> cellIterator = row.cellIterator();
while(cellIterator.hasNext())
{
Cell cell = cellIterator.next();
switch(cell.getCellType())
{
case Cell.CELL_TYPE_BOOLEAN:
System.out.println("boolean===>>>"+cell.getBooleanCellValue() + "\t");
break;
case Cell.CELL_TYPE_NUMERIC:
System.out.println("numeric===>>>"+cell.getNumericCellValue() + "\t");
break;
case Cell.CELL_TYPE_STRING:
System.out.println("String===>>>"+cell.getStringCellValue() + "\t");
break;
}
}
System.out.println("");
}
file.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}

How to run this program which read excel using POI

I've try to run this code in eclipse but I've get this: selection does not contain a main type eclipse.
Does anyone know how I will do it? I am newbie in java and I need help!
The program I try to make is to read excel file using POI! :)
import java.io.File;
import java.io.FileInputStream;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;
public class sample2 {
private void sample2(test)
FileInputStream file = new FileInputStream(new File("C:\\test.xls"));
//Get the workbook instance for XLS file
HSSFWorkbook workbook = new HSSFWorkbook(test);
//Get first sheet from the workbook
HSSFSheet sheet = workbook.getSheetAt(0);
//Get iterator to all the rows in current sheet
Iterator<Row> rowIterator = sheet.iterator();
//Get iterator to all cells of current row
Iterator<Cell> cellIterator = row.cellIterator();
try {
FileInputStream file = new FileInputStream(new File("C:\\test.xls"));
//Get the workbook instance for XLS file
HSSFWorkbook workbook = new HSSFWorkbook(file);
//Get first sheet from the workbook
HSSFSheet sheet = workbook.getSheetAt(0);
//Iterate through each rows from first sheet
Iterator<Row> rowIterator = sheet.iterator();
while(rowIterator.hasNext()) {
Row row = rowIterator.next();
//For each row, iterate through each columns
Iterator<Cell> cellIterator = row.cellIterator();
while(cellIterator.hasNext()) {
Cell cell = cellIterator.next();
switch(cell.getCellType()) {
case Cell.CELL_TYPE_BOOLEAN:
System.out.print(cell.getBooleanCellValue() + "\t\t");
break;
case Cell.CELL_TYPE_NUMERIC:
System.out.print(cell.getNumericCellValue() + "\t\t");
break;
case Cell.CELL_TYPE_STRING:
System.out.print(cell.getStringCellValue() + "\t\t");
break;
}
}
System.out.println("");
}
file.close();
FileOutputStream out =
new FileOutputStream(new File("C:\\test.xls"));
workbook.write(out);
out.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

You cannot run a Java application without a main method.
You need something like the following:
public static void main(String[] args) {
sample2 s = new sample2();
s.sample();
}
Also your code contains a lot of errors. You are:
Missing a main method
Capitalization is wrong
Miss types on the input argument for the sample2 method (String test?)
The code is broken many ways. You duplicated the code to read files twice, for error handling, etc.
Reading a good tutorial on Java would help greatly here. A great tutorial on Java and Excel can be found here, and pay some attention to the main method, that's the entry of your Java application.

Your code will not compile due to the identifier "test" in the sample2 method. Remove it and to run the program :
Just add the following method:
public static void main(String[] args) {
new sample2().sample2();
}