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Exporting JTable Data including Table Headers to Excel File

I need help regarding this, I can't get it right. I want to export JTable data to excel file. There is no error but I am getting only the data it shows and does not include the table headers.
I am running this in a Netbeans 8.2 IDE and had also imported the essential jar files.
Data on my jtable is provided by my mysql database and I need to export it from jtable to an excel file.
Anyway tblData is my JTable variable name.
private void btnExportActionPerformed(java.awt.event.ActionEvent evt) {
FileOutputStream excelFOS = null;
BufferedOutputStream excelBOS = null;
XSSFWorkbook wb = null;
JFileChooser excelFileChooser = new JFileChooser();
excelFileChooser.setDialogTitle("Save As");
FileNameExtensionFilter fnef = new FileNameExtensionFilter("Excel Files","xls","xlsx","ods");
excelFileChooser.setFileFilter(fnef);
int excelChooser = excelFileChooser.showSaveDialog(null);
if(excelChooser == JFileChooser.APPROVE_OPTION){
try {
wb = new XSSFWorkbook();
XSSFSheet sheet = wb.createSheet("Data Sheet");
for(int i = 0; i < tblData.getRowCount(); i++){
XSSFRow excelRow = sheet.createRow(i);
for(int j = 0; j < tblData.getColumnCount(); j++){
XSSFCell excelCell = excelRow.createCell(j);
excelCell.setCellValue(tblData.getValueAt(i, j).toString());
}
}
excelFOS = new FileOutputStream(excelFileChooser.getSelectedFile() + ".xlsx");
excelBOS = new BufferedOutputStream(excelFOS);
wb.write(excelBOS);
JOptionPane.showMessageDialog(null, "Successfully saved.");
} catch (FileNotFoundException ex) {
ex.printStackTrace();
} catch (IOException ex) {
ex.printStackTrace();
} finally {
try {
if(excelBOS != null){
excelBOS.close();
}
if(excelFOS != null){
excelFOS.close();
}
if(wb != null){
wb.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
} //---- end finally
} //---- end if condition
}
I am expecting for the header to be exported. Can anyone help me with this.

Not really clear what tblData is in your provided code. But If I would have the requirement to export a JTable to Excel, then I would go by TableModel of the JTable. First write the column names to first row of the Excel sheet using TableModel.getColumnName. Then write the table data to next rows of the Excelsheet using TableModel.getValueAt.
Complete example:
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import java.io.FileOutputStream;
import javax.swing.JTable;
import javax.swing.table.TableModel;
class WriteJTableToExcel {
static void exportToExcel(JTable table, String filePath) throws Exception {
TableModel model = table.getModel();
Workbook workbook = new XSSFWorkbook();
Sheet sheet = workbook.createSheet();
Row row;
Cell cell;
// write the column headers
row = sheet.createRow(0);
for (int c = 0; c < model.getColumnCount(); c++) {
cell = row.createCell(c);
cell.setCellValue(model.getColumnName(c));
}
// write the data rows
for (int r = 0; r < model.getRowCount(); r++) {
row = sheet.createRow(r+1);
for (int c = 0; c < model.getColumnCount(); c++) {
cell = row.createCell(c);
Object value = model.getValueAt(r, c);
if (value instanceof String) {
cell.setCellValue((String)value);
} else if (value instanceof Double) {
cell.setCellValue((Double)value);
}
}
}
FileOutputStream out = new FileOutputStream(filePath);
workbook.write(out);
out.close();
workbook.close();
}
public static void main(String[] args) throws Exception {
Object columnNames[] = {"Name", "Amount", "Factor"};
Object rowData[][] = {
{"Bob", 12.0, 3.0},
{"Alice", 34.0, 2.5},
{"Jack", 56.0, 2.0},
{"John", 78.0, 1.5}
};
JTable table = new JTable(rowData, columnNames);
exportToExcel(table, "./Excel.xlsx");
}
}

you need to export the getTableHeader() from your jTable separately before you export your data. It is not stored together with the data, as it is in an Excel workbook.
Hope that helps :-)

upload large .xlsx file in gui java

i have a large excel file containing 600.000 rows , i used XSSFWorkbook to upload the excel file at a Jtable in my GUI but it takes about 15 minutes to be done in eclipse and once i export my project to a jar file i can't do it even in the 15 minutes . Any help please ?
Here is the method , that i found in internet to upload my excel file .
void fillData(File file) {
int index = -1;
XSSFWorkbook workbook = null;
try {
try {
String f = file.getPath();
File file1 = new File(f);
OPCPackage opcPackage = OPCPackage.open(file1);
workbook = new XSSFWorkbook(opcPackage);
} catch (IOException ex) {
Logger.getLogger(ProjectApp3.class.getName()).log(Level.SEVERE, null, ex);
}
String[] strs = new String[workbook.getNumberOfSheets()];
//get all sheet names from selected workbook
for (int i = 0; i < strs.length; i++) {
strs[i] = workbook.getSheetName(i);
}
JFrame frame = new JFrame("Input Dialog");
//select sheet
String selectedsheet = (String) JOptionPane.showInputDialog(
frame, "Which worksheet you want to import ?", "Select Worksheet",
JOptionPane.QUESTION_MESSAGE, null, strs, strs[0]);
if (selectedsheet != null) {
for (int i = 0; i < strs.length; i++) {
if (workbook.getSheetName(i).equalsIgnoreCase(selectedsheet))
index = i;
}
XSSFSheet sheet = workbook.getSheetAt(index);
XSSFRow row = sheet.getRow(0);
//import headers data
headers.clear();
for (int i = 0; i < row.getLastCellNum(); i++) {
XSSFCell cell1 = row.getCell(i);
headers.add(cell1.toString());
}
//import data
data1.clear();
for (int j = 1; j < sheet.getLastRowNum() + 1; j++) {
Vector d = new Vector();
row = sheet.getRow(j);
int noofrows = row.getLastCellNum();
for (int i = 0; i < noofrows; i++) { //To handle empty excel cells
XSSFCell cell = row.getCell(i,
org.apache.poi.ss.usermodel.Row.MissingCellPolicy.CREATE_NULL_AS_BLANK);
d.add(cell.toString());
}
d.add("\n");
data1.add(d);
}
} else {
return;
}
} catch (Exception e) {
e.printStackTrace();
}
}

I think the basic problem is that you're trying to give. your Jtable all the data at startup. This is going to be deeply problematic. You may want to write a custom subclass from AbstractTableModel. See the docs for Jtable that includes this:
TableModel dataModel = new AbstractTableModel() {
public int getColumnCount() { return 10; }
public int getRowCount() { return 10;}
public Object getValueAt(int row, int col) { return new Integer(row*col); }
};
JTable table = new JTable(dataModel);
JScrollPane scrollpane = new JScrollPane(table);
You can implement those three methods based on the info that POI gives you. But do lazy loading of the data, most especially for getValueAt(). Keep the spreadsheet file open and grab the data only when the user scrolls to view it.

export jtable to excel in java netbeans [duplicate]

This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 6 years ago.
i have written the following code with some help from google for exporting jtable to excel but i am not able to export it to excel and i am also getting null pointer .
cell.setCellValue(model.getValueAt(i, j).toString());
the whole code is
try {
HSSFWorkbook fWorkbook = new HSSFWorkbook();
HSSFSheet fSheet;
fSheet = fWorkbook.createSheet("new Sheet");
HSSFFont sheetTitleFont = fWorkbook.createFont();
File file = new File("D:\\MOHIT\\bill report\\report.xls");
HSSFCellStyle cellStyle = fWorkbook.createCellStyle();
sheetTitleFont.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
//sheetTitleFont.setColor();
TableModel model = report_table.getModel();
TableColumnModel model1 = report_table.getTableHeader().getColumnModel();
HSSFRow fRow1 = fSheet.createRow((short) 0);
for (int i = 0; i < model1.getColumnCount(); i++){
HSSFCell cell = fRow1.createCell((short) i);
cell.setCellValue(model1.getColumn(i).getHeaderValue().toString());
}
for (int i = 1; i < model.getRowCount(); i++) {
HSSFRow fRow = fSheet.createRow((short) i);
for (int j = 1; j < model.getColumnCount(); j++) {
HSSFCell cell = fRow.createCell((short) j);
cell.setCellValue(model.getValueAt(i, j).toString());
cell.setCellStyle(cellStyle);
}
}
FileOutputStream fileOutputStream;
fileOutputStream = new FileOutputStream(file);
try (BufferedOutputStream bos = new BufferedOutputStream(fileOutputStream)) {
fWorkbook.write(bos);
}
fileOutputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
can somebody tell me why am i getting null pointer exception how to correct it.

Try to replace
cell.setCellValue(model.getValueAt(i, j).toString());
by
cell.setCellValue(Objects.toString(model.getValueAt(i, j), ""));
And look the link which I've posted in my comment.
P.S. Class Objects is defined in the package java.util

FileOutputStream (Apachhe POI) taking too long time to save

When I am edit a .xlsx file using Apache poi, its taking too long to save. The .xlsx file contains, formulas formatting and freeze pane. I am using the following code,
try {
FileInputStream file = new FileInputStream(new File(path));
XSSFWorkbook fWorkbook = new XSSFWorkbook(file);
XSSFSheet fSheet = fWorkbook.getSheetAt(0);
for(int i = 0; i < jTable1.getRowCount(); i++){
if(jTable1.getModel().getValueAt(i, index1).equals("1")){
XSSFCell cell = fSheet.getRow(i+1).getCell(index1);
cell.setCellType(XSSFCell.CELL_TYPE_NUMERIC);
cell.setCellValue(new Double(1));
XSSFCellStyle cs = fWorkbook.createCellStyle();
cs.setDataFormat(fWorkbook.getCreationHelper().createDataFormat().getFormat("dd/MMMM/yyyy"));
cell =fSheet.getRow(i+1).getCell(index2);
cell.setCellValue(new Date());
cell.setCellStyle(cs);
}
}
file.close();
FileOutputStream fileOutputStream = new FileOutputStream(path);
fWorkbook.write(fileOutputStream);
fileOutputStream.close();
JOptionPane.showMessageDialog(this, "Data saved successfully.");
parent.removeContent();
}catch(Exception e){
e.printStackTrace();
}
Edit 1:
The excel file: http://ge.tt/5orGWSJ2/v/0?c
Loading Data into JTable from Excel:
try {
FileInputStream file1 = new FileInputStream(new File("c:\\sample.xlsx"));
XSSFWorkbook workbook = new XSSFWorkbook(file1);
XSSFSheet sheet = workbook.getSheetAt(0);
int rowc=sheet.getLastRowNum()+1;
int colc=sheet.getRow(0).getLastCellNum();
Object heading[] = new Object[colc+1];
XSSFRow row1 = sheet.getRow(0);
for(int i=0, column =0; i < colc; i++){
if(i == 1){
heading[column++] = "";
}
heading[column++] = cellToString(row1.getCell(i));
}
Object [][]j=new Object[rowc-1][colc+1];
for (int i = 1; i < rowc; i++) {
row1 = sheet.getRow(i);
for (int jj = 0, column = 0; jj < colc; jj++) {
if(column == 1){
j[i-1][column++] = new Boolean(false);
j[i-1][column] = cellToString(row1.getCell(jj));
}
else{
j[i-1][column]=cellToString(row1.getCell(jj));
}
column++;
}
}
jTable1.setModel(new DefaultTableModel(j, heading){
public Class getColumnClass(int columnIndex) {
if(columnIndex == 0){
return java.lang.Integer.class;
}
else if(columnIndex == 1){
return java.lang.Boolean.class;
}
else{
return java.lang.Object.class;
}
}
});
jTable1.getColumnModel().getColumn(1).setMaxWidth(60);
jTable1.setAutoResizeMode( JTable.AUTO_RESIZE_OFF );
jTable1.getTableHeader().setReorderingAllowed(false);
} catch (IOException ex) {
JOptionPane.showMessageDialog(BarcodePrint.this, ex);
}
Writing data into excel after editing column BarcodePrint:
try {
FileInputStream file = new FileInputStream(new File("c:\\sample.xlsx"));
XSSFWorkbook fWorkbook = new XSSFWorkbook(file);
XSSFCellStyle cs = fWorkbook.createCellStyle();
cs.setDataFormat(fWorkbook.getCreationHelper().createDataFormat().getFormat("dd/MMMM/yyyy"));
Date currentdate = new Date();
XSSFSheet fsheet = fWorkbook.getSheetAt(0);
Double barcodeprintstatus = new Double(1);
int newindex = 24;
int printdate = 26;
int uniqueid = 27;
for(int i = 0; i < jTable1.getModel().getRowCount(); i++){
if(jTable1.getModel().getValueAt(i, newindex).equals("1")){
for(int k=1; k < fsheet.getPhysicalNumberOfRows(); k++){
XSSFCell cell = fsheet.getRow(k).getCell(uniqueid-1);
String uid = cell.getRawValue();
if(jTable1.getModel().getValueAt(i, uniqueid).toString().equals(uid)){
cell = (fsheet.getRow(i+1)).getCell(newindex-1);
cell.setCellType(XSSFCell.CELL_TYPE_NUMERIC);
cell.setCellValue(barcodeprintstatus);
cell = fsheet.getRow(i+1).getCell(printdate-1);
cell.setCellValue(currentdate);
cell.setCellStyle(cs);
}
}
}
}
file.close();
FileOutputStream fileOutputStream = new FileOutputStream("c:\\sample.xlsx");
fWorkbook.write(fileOutputStream); // this is taking so much of time. Approximately 1 min.
fileOutputStream.close();
}catch(Exception e){
e.printStackTrace();
}
I am unable to solve this problem. fWorkbook.write(fileOutputStream); is taking so much of time as I mentioned above. Please help. Is there any other way to save the excel file? Or can I write data partially for a single column rather than the hole workbook?

Try to improve the code.
You call fSheet.getRow(i+1) twice. Try to introduce a variable and reuse the row rather than obtain it.
cell.setCellValue(new Double(1));
Create the 1 double once before the for loop and reuse it.
XSSFCellStyle cs = fWorkbook.createCellStyle();
cs.setDataFormat(fWorkbook.getCreationHelper().createDataFormat().getFormat("dd/MMMM/yyyy"));
Move the cell style creation and initializing out of the for loop. Create it before the loop and reuse.
cell.setCellValue(new Date());
Introduce a Date variable and create the Date just once. Again before the for loop.

Add a BufferedOutputStream around the FileOutputStream.

Exporting Jtable into the Excelsheet using HSSFWorkbook

Hello I am trying to Export Jtable Data into the Excel Sheet using HSSFWorkbook. and i am getting all the content what Table have but i am not getting Table Headers please can anyone help for the same.
Here the Command used for Taking content of the Jtable.
try {
HSSFWorkbook fWorkbook = new HSSFWorkbook();
HSSFSheet fSheet = fWorkbook.createSheet("new Sheet");
HSSFFont sheetTitleFont = fWorkbook.createFont();
File file = new File("/home/kishan/NetBeansProjects/JavaChecking/src/com/verve/SwingChecking/book.xls");
HSSFCellStyle cellStyle = fWorkbook.createCellStyle();
sheetTitleFont.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
//sheetTitleFont.setColor();
TableModel model = jTable1.getModel();
for (int i = 0; i < model.getRowCount(); i++) {
HSSFRow fRow = fSheet.createRow((short) i);
for (int j = 0; j < model.getColumnCount(); j++) {
HSSFCell cell = fRow.createCell((short) j);
cell.setCellValue(model.getValueAt(i, j).toString());
cell.setCellStyle(cellStyle);
}
}
FileOutputStream fileOutputStream;
fileOutputStream = new FileOutputStream(file);
BufferedOutputStream bos = new BufferedOutputStream(fileOutputStream);
fWorkbook.write(bos);
bos.close();
fileOutputStream.close();
}catch(Exception e){
}
for (int i = 0; i < model.getColumnCount(); i++) {
HSSFRow fRow = fSheet.createRow((short) i);
for(int j = 0; j < model.getColumnCount(); j++) {
HSSFCell cell = fRow.createCell((short) j);
cell.setCellValue(model.getValueAt(i, j).toString());
System.out.println(model.getColumnName(j));
}
}
last for loop is not addind data of table header.
and i am getting this excel file
how to get Table header along with that??

Here's my implementation of the HSSF Workbook from the answers in this thread.
I created a class ExcelWriter then a Method Writer which takes two parameters; the JTable and the FileLocation to be used.
import java.io.BufferedOutputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import javax.swing.JTable;
import javax.swing.table.TableColumnModel;
import javax.swing.table.TableModel;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
/**
*
* #author oluwajayi
*/
public class ExcelWriter {
public static void Writer (JTable jTable1, String Location) throws FileNotFoundException, IOException {
HSSFWorkbook fWorkbook = new HSSFWorkbook();
HSSFSheet fSheet = fWorkbook.createSheet("new Sheet");
HSSFFont sheetTitleFont = fWorkbook.createFont();
HSSFCellStyle cellStyle = fWorkbook.createCellStyle();
sheetTitleFont.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
//sheetTitleFont.setColor();
TableModel model = jTable1.getModel();
//Get Header
TableColumnModel tcm = jTable1.getColumnModel();
HSSFRow hRow = fSheet.createRow((short) 0);
for(int j = 0; j < tcm.getColumnCount(); j++) {
HSSFCell cell = hRow.createCell((short) j);
cell.setCellValue(tcm.getColumn(j).getHeaderValue().toString());
cell.setCellStyle(cellStyle);
}
//Get Other details
for (int i = 0; i < model.getRowCount(); i++) {
HSSFRow fRow = fSheet.createRow((short) i+1);
for (int j = 0; j < model.getColumnCount(); j++) {
HSSFCell cell = fRow.createCell((short) j);
cell.setCellValue(model.getValueAt(i, j).toString());
cell.setCellStyle(cellStyle);
}
}
FileOutputStream fileOutputStream;
fileOutputStream = new FileOutputStream(Location);
try (BufferedOutputStream bos = new BufferedOutputStream(fileOutputStream)) {
fWorkbook.write(bos);
}
fileOutputStream.close();
}
}

Something like this to add Column Names in the first row of your sheet:
TableColumnModel tcm = jTable1.getColumnModel();
HSSFRow fRow = fSheet.createRow((short) 0);
for(int j = 0; j < tcm.getColumnCount(); j++) {
HSSFCell cell = fRow.createCell((short) j);
cell.setCellValue(tcm.getColumn(j).getHeaderValue().toString());
}
You could run this first and then add the table data starting from the second row.

you are only writing the data in the TableModel to the workbook. This model does not contain the table header. Take a look at JTable.getTableHeader()
for example:
public class JTableExport {
public static void main(String[] args) {
Object[] columnNames = new Object[] {"column1", "column2"};
JTable table = new JTable(new Object[0][0], columnNames);
TableColumnModel model = table.getTableHeader().getColumnModel();
for (int i = 0; i < model.getColumnCount(); i++) {
System.out.println(model.getColumn(i).getHeaderValue());
}
}
}
this code prints
column1
column2

for(int j = 0; j < tcm.getColumnCount(); j++) {
HSSFCell cell = fRow.createCell((short) j);
cell.setCellValue(tcm.getColumn(j).getHeaderValue().toString());
}
for(int j = 0; j < tcm.getRowCount(); j++) {
HSSFCell cell = fRow.createCell((short) j);
cell.setCellValue(tcm.getColumn(j).getHeaderValue().toString());
}

I created this code:
public void Export() {
JFileChooser save = new JFileChooser();
save.setDialogTitle("Save as...");
save.setFileFilter(new FileNameExtensionFilter("xls", "xlsx", "xlsm"));
int choose = save.showSaveDialog(null);
if(choose == JFileChooser.APPROVE_OPTION) {
XSSFWorkbook export = new XSSFWorkbook();
XSSFSheet sheet1 = export.createSheet("new file");
try{
TableModel tableModel = showQuery.getModel();
for(int i=0; i<tableModel.getRowCount(); i++) {
XSSFRow newRow = sheet1.createRow(i);
for(int j=0; j<tableModel.getColumnCount(); j++) {
XSSFCell newCell = newRow.createCell((short) j);
if(i==0){
XSSFCellStyle style = export.createCellStyle();
style.setFillForegroundColor(IndexedColors.GREY_40_PERCENT.getIndex());
style.setFillPattern(XSSFCellStyle.SOLID_FOREGROUND);
style.setBorderBottom(BorderStyle.THIN);
style.setBorderTop(BorderStyle.THIN);
style.setBorderLeft(BorderStyle.THIN);
style.setBorderRight(BorderStyle.THIN);
newCell.setCellStyle(style);
newCell.setCellValue(tableModel.getColumnName(j));
} else {
XSSFCellStyle style = export.createCellStyle();
style.setBorderBottom(BorderStyle.THIN);
style.setBorderTop(BorderStyle.THIN);
style.setBorderLeft(BorderStyle.THIN);
style.setBorderRight(BorderStyle.THIN);
newCell.setCellStyle(style);
newCell.setCellValue(tableModel.getValueAt(i, j).toString());
}
}
}
FileOutputStream otp = new FileOutputStream(save.getSelectedFile()+".xlsx");
BufferedOutputStream bos = new BufferedOutputStream(otp);
export.write(bos);
bos.close();
otp.close();
JOptionPane.showMessageDialog(null, "Arquivo exprtado com sucesso!");
}catch(Exception e) {
JOptionPane.showMessageDialog(null, e);
}
}
}