Converting issue in java - xlsx to csv problem - java

I am currently working on a small program to automatically convert xlsx files to csv, but it does not really work.
It has an input file and an output file, the details are in the codesnippet.
You need the followings:
import java.io.*;
import java.util.Iterator;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
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;
Can you please help me fix it? Thanks
static void convertToXlsx(File inputFile, File outputFile) {
// For storing data into CSV files
StringBuffer cellValue = new StringBuffer();
try {
FileOutputStream fos = new FileOutputStream(outputFile);
// Get the workbook instance for XLSX file
XSSFWorkbook wb = new XSSFWorkbook(new FileInputStream(inputFile));
// Get first sheet from the workbook
XSSFSheet sheet = wb.getSheetAt(0);
Row row;
Cell cell;
// Iterate through each rows from first sheet
Iterator<Row> rowIterator = sheet.iterator();
while (rowIterator.hasNext()) {
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:
cellValue.append(cell.getBooleanCellValue() + ",");
break;
case Cell.CELL_TYPE_NUMERIC:
cellValue.append(cell.getNumericCellValue() + ",");
break;
case Cell.CELL_TYPE_STRING:
cellValue.append(cell.getStringCellValue() + ",");
break;
case Cell.CELL_TYPE_BLANK:
cellValue.append("" + ",");
break;
default:
cellValue.append(cell + ",");
}
}
}
fos.write(cellValue.toString().getBytes());
fos.close();
} catch (Exception e) {
System.err.println("Exception :" + e.getMessage());
}
}
static void convertToXls(File inputFile, File outputFile) {
StringBuffer cellDData = new StringBuffer();
try {
FileOutputStream fos = new FileOutputStream(outputFile);
// Get the workbook instance for XLS file
HSSFWorkbook workbook = new HSSFWorkbook(new FileInputStream(inputFile));
// Get first sheet from the workbook
HSSFSheet sheet = workbook.getSheetAt(0);
Cell cell;
Row row;
// Iterate through each rows from first sheet
Iterator<Row> rowIterator = sheet.iterator();
while (rowIterator.hasNext()) {
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:
cellDData.append(cell.getBooleanCellValue() + ",");
break;
case Cell.CELL_TYPE_NUMERIC:
cellDData.append(cell.getNumericCellValue() + ",");
break;
case Cell.CELL_TYPE_STRING:
cellDData.append(cell.getStringCellValue() + ",");
break;
case Cell.CELL_TYPE_BLANK:
cellDData.append("" + ",");
break;
default:
cellDData.append(cell + ",");
}
}
}
fos.write(cellDData.toString().getBytes());
fos.close();
} catch (FileNotFoundException e) {
System.err.println("Exception" + e.getMessage());
} catch (IOException e) {
System.err.println("Exception" + e.getMessage());
}
}
public static void main(String[] args) {
File inputFile = new File("C:\input.xls");
File outputFile = new File("C:\output1.csv");
File inputFile2 = new File("C:\\Users\\lendvaigy\\Desktop\\AKK\\DOWNLOAD TEST\\legjobb-eladasi-es-veteli-hozamok-arfolyamok.xlsx");
File outputFile2 = new File("C:\\Users\\lendvaigy\\Desktop\\AKK\\DOWNLOAD TEST\\legjobb-eladasi-es-veteli-hozamok-arfolyamok.csv");
convertToXls(inputFile, outputFile);
convertToXlsx(inputFile2, outputFile2);
}
The main problem is that I am not a professional one, just a DIY rookie trying to create small programs.

The problem in your code is in convertToXls(). For converting xls to csv file use XSSFWorkbook instead of HSSFWorkbook.
Try changing following in convertToXls().
static void convertToXls(File inputFile, File outputFile) throws IOException {
Workbook wb = new XSSFWorkbook(inputFile.getPath());
DataFormatter formatter = new DataFormatter();
PrintStream out = new PrintStream(new FileOutputStream(outputFile), true, "UTF-8");
Sheet sheet =wb.getSheetAt(0);
for (Row row : sheet) {
boolean firstCell = true;
for (Cell cell : row) {
if (!firstCell)
out.print(',');
String text = formatter.formatCellValue(cell);
out.print(text);
firstCell = false;
}
out.println();
}
}
And rest should work as it is.

Related

Retrieving selective sheet data from "large Excel 2003" file using java [duplicate]

I want to read and write an Excel file from Java with 3 columns and N rows, printing one string in each cell. Can anyone give me simple code snippet for this? Do I need to use any external lib or does Java have built-in support for it?
I want to do the following:
for(i=0; i <rows; i++)
//read [i,col1] ,[i,col2], [i,col3]
for(i=0; i<rows; i++)
//write [i,col1], [i,col2], [i,col3]
Try the Apache POI HSSF. Here's an example on how to read an excel file:
try {
POIFSFileSystem fs = new POIFSFileSystem(new FileInputStream(file));
HSSFWorkbook wb = new HSSFWorkbook(fs);
HSSFSheet sheet = wb.getSheetAt(0);
HSSFRow row;
HSSFCell cell;
int rows; // No of rows
rows = sheet.getPhysicalNumberOfRows();
int cols = 0; // No of columns
int tmp = 0;
// This trick ensures that we get the data properly even if it doesn't start from first few rows
for(int i = 0; i < 10 || i < rows; i++) {
row = sheet.getRow(i);
if(row != null) {
tmp = sheet.getRow(i).getPhysicalNumberOfCells();
if(tmp > cols) cols = tmp;
}
}
for(int r = 0; r < rows; r++) {
row = sheet.getRow(r);
if(row != null) {
for(int c = 0; c < cols; c++) {
cell = row.getCell((short)c);
if(cell != null) {
// Your code here
}
}
}
}
} catch(Exception ioe) {
ioe.printStackTrace();
}
On the documentation page you also have examples of how to write to excel files.
Apache POI can do this for you. Specifically the HSSF module. The quick guide is most useful. Here's how to do what you want - specifically create a sheet and write it out.
Workbook wb = new HSSFWorkbook();
//Workbook wb = new XSSFWorkbook();
CreationHelper createHelper = wb.getCreationHelper();
Sheet sheet = wb.createSheet("new sheet");
// Create a row and put some cells in it. Rows are 0 based.
Row row = sheet.createRow((short)0);
// Create a cell and put a value in it.
Cell cell = row.createCell(0);
cell.setCellValue(1);
// Or do it on one line.
row.createCell(1).setCellValue(1.2);
row.createCell(2).setCellValue(
createHelper.createRichTextString("This is a string"));
row.createCell(3).setCellValue(true);
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("workbook.xls");
wb.write(fileOut);
fileOut.close();
First add all these jar files in your project class path:
poi-scratchpad-3.7-20101029
poi-3.2-FINAL-20081019
poi-3.7-20101029
poi-examples-3.7-20101029
poi-ooxml-3.7-20101029
poi-ooxml-schemas-3.7-20101029
xmlbeans-2.3.0
dom4j-1.6.1
Code for writing in a excel file:
public static void main(String[] args) {
//Blank workbook
XSSFWorkbook workbook = new XSSFWorkbook();
//Create a blank sheet
XSSFSheet sheet = workbook.createSheet("Employee Data");
//This data needs to be written (Object[])
Map<String, Object[]> data = new TreeMap<String, Object[]>();
data.put("1", new Object[]{"ID", "NAME", "LASTNAME"});
data.put("2", new Object[]{1, "Amit", "Shukla"});
data.put("3", new Object[]{2, "Lokesh", "Gupta"});
data.put("4", new Object[]{3, "John", "Adwards"});
data.put("5", new Object[]{4, "Brian", "Schultz"});
//Iterate over data and write to sheet
Set<String> keyset = data.keySet();
int rownum = 0;
for (String key : keyset)
{
//create a row of excelsheet
Row row = sheet.createRow(rownum++);
//get object array of prerticuler key
Object[] objArr = data.get(key);
int cellnum = 0;
for (Object obj : objArr)
{
Cell cell = row.createCell(cellnum++);
if (obj instanceof String)
{
cell.setCellValue((String) obj);
}
else if (obj instanceof Integer)
{
cell.setCellValue((Integer) obj);
}
}
}
try
{
//Write the workbook in file system
FileOutputStream out = new FileOutputStream(new File("C:\\Documents and Settings\\admin\\Desktop\\imp data\\howtodoinjava_demo.xlsx"));
workbook.write(out);
out.close();
System.out.println("howtodoinjava_demo.xlsx written successfully on disk.");
}
catch (Exception e)
{
e.printStackTrace();
}
}
Code for reading from excel file
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
public static void main(String[] args) {
try {
FileInputStream file = new FileInputStream(new File("C:\\Documents and Settings\\admin\\Desktop\\imp data\\howtodoinjava_demo.xlsx"));
//Create Workbook instance holding reference to .xlsx file
XSSFWorkbook workbook = new XSSFWorkbook(file);
//Get first/desired sheet from the workbook
XSSFSheet sheet = workbook.getSheetAt(0);
//Iterate through each rows one by one
Iterator<Row> rowIterator = sheet.iterator();
while (rowIterator.hasNext())
{
Row row = rowIterator.next();
//For each row, iterate through all the columns
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext())
{
Cell cell = cellIterator.next();
//Check the cell type and format accordingly
switch (cell.getCellType())
{
case Cell.CELL_TYPE_NUMERIC:
System.out.print(cell.getNumericCellValue() + "\t");
break;
case Cell.CELL_TYPE_STRING:
System.out.print(cell.getStringCellValue() + "\t");
break;
}
}
System.out.println("");
}
file.close();
} catch (Exception e) {
e.printStackTrace();
}
}
You can also consider JExcelApi. I find it better designed than POI. There's a tutorial here.
There is a new easy and very cool tool (10x to Kfir): xcelite
Write:
public class User {
#Column (name="Firstname")
private String firstName;
#Column (name="Lastname")
private String lastName;
#Column
private long id;
#Column
private Date birthDate;
}
Xcelite xcelite = new Xcelite();
XceliteSheet sheet = xcelite.createSheet("users");
SheetWriter<User> writer = sheet.getBeanWriter(User.class);
List<User> users = new ArrayList<User>();
// ...fill up users
writer.write(users);
xcelite.write(new File("users_doc.xlsx"));
Read:
Xcelite xcelite = new Xcelite(new File("users_doc.xlsx"));
XceliteSheet sheet = xcelite.getSheet("users");
SheetReader<User> reader = sheet.getBeanReader(User.class);
Collection<User> users = reader.read();
For reading a xlsx file we can use Apache POI libs
Try this:
public static void readXLSXFile() throws IOException
{
InputStream ExcelFileToRead = new FileInputStream("C:/Test.xlsx");
XSSFWorkbook wb = new XSSFWorkbook(ExcelFileToRead);
XSSFWorkbook test = new XSSFWorkbook();
XSSFSheet sheet = wb.getSheetAt(0);
XSSFRow row;
XSSFCell cell;
Iterator rows = sheet.rowIterator();
while (rows.hasNext())
{
row=(XSSFRow) rows.next();
Iterator cells = row.cellIterator();
while (cells.hasNext())
{
cell=(XSSFCell) cells.next();
if (cell.getCellType() == XSSFCell.CELL_TYPE_STRING)
{
System.out.print(cell.getStringCellValue()+" ");
}
else if(cell.getCellType() == XSSFCell.CELL_TYPE_NUMERIC)
{
System.out.print(cell.getNumericCellValue()+" ");
}
else
{
//U Can Handel Boolean, Formula, Errors
}
}
System.out.println();
}
}
.csv or POI will certainly do it, but you should be aware of Andy Khan's JExcel. I think it's by far the best Java library for working with Excel there is.
A simple CSV file should suffice
String path="C:\\Book2.xlsx";
try {
File f = new File( path );
Workbook wb = WorkbookFactory.create(f);
Sheet mySheet = wb.getSheetAt(0);
Iterator<Row> rowIter = mySheet.rowIterator();
for ( Iterator<Row> rowIterator = mySheet.rowIterator() ;rowIterator.hasNext(); )
{
for ( Iterator<Cell> cellIterator = ((Row)rowIterator.next()).cellIterator() ; cellIterator.hasNext() ; )
{
System.out.println ( ( (Cell)cellIterator.next() ).toString() );
}
System.out.println( " **************************************************************** ");
}
} catch ( Exception e )
{
System.out.println( "exception" );
e.printStackTrace();
}
and make sure to have added the jars poi and poi-ooxml (org.apache.poi) to your project
For reading data from .xlsx workbooks we need to use XSSFworkbook classes.
XSSFWorkbook xlsxBook = new XSSFWorkbook(fis);
XSSFSheet sheet = xlsxBook.getSheetAt(0); etc.
We need to use Apache-poi 3.9 # http://poi.apache.org/
For detailed info with example visit
: http://java-recent.blogspot.in
Sure , you will find the code below useful and easy to read and write. This is a util class which you can use in your main method and then you are good to use all methods below.
public class ExcelUtils {
private static XSSFSheet ExcelWSheet;
private static XSSFWorkbook ExcelWBook;
private static XSSFCell Cell;
private static XSSFRow Row;
File fileName = new File("C:\\Users\\satekuma\\Pro\\Fund.xlsx");
public void setExcelFile(File Path, String SheetName) throws Exception
try {
FileInputStream ExcelFile = new FileInputStream(Path);
ExcelWBook = new XSSFWorkbook(ExcelFile);
ExcelWSheet = ExcelWBook.getSheet(SheetName);
} catch (Exception e) {
throw (e);
}
}
public static String getCellData(int RowNum, int ColNum) throws Exception {
try {
Cell = ExcelWSheet.getRow(RowNum).getCell(ColNum);
String CellData = Cell.getStringCellValue();
return CellData;
} catch (Exception e) {
return "";
}
}
public static void setCellData(String Result, int RowNum, int ColNum, File Path) throws Exception {
try {
Row = ExcelWSheet.createRow(RowNum - 1);
Cell = Row.createCell(ColNum - 1);
Cell.setCellValue(Result);
FileOutputStream fileOut = new FileOutputStream(Path);
ExcelWBook.write(fileOut);
fileOut.flush();
fileOut.close();
} catch (Exception e) {
throw (e);
}
}
}
using spring apache poi repo
if (fileName.endsWith(".xls")) {
File myFile = new File("file location" + fileName);
FileInputStream fis = new FileInputStream(myFile);
org.apache.poi.ss.usermodel.Workbook workbook = null;
try {
workbook = WorkbookFactory.create(fis);
} catch (InvalidFormatException e) {
e.printStackTrace();
}
org.apache.poi.ss.usermodel.Sheet sheet = workbook.getSheetAt(0);
Iterator<Row> rowIterator = sheet.iterator();
while (rowIterator.hasNext()) {
Row row = rowIterator.next();
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
switch (cell.getCellType()) {
case Cell.CELL_TYPE_STRING:
System.out.print(cell.getStringCellValue());
break;
case Cell.CELL_TYPE_BOOLEAN:
System.out.print(cell.getBooleanCellValue());
break;
case Cell.CELL_TYPE_NUMERIC:
System.out.print(cell.getNumericCellValue());
break;
}
System.out.print(" - ");
}
System.out.println();
}
}
I edited the most voted one a little cuz it didn't count blanks columns or rows well not totally, so here is my code i tested it and now can get any cell in any part of an excel file. also now u can have blanks columns between filled column and it will read them
try {
POIFSFileSystem fs = new POIFSFileSystem(new FileInputStream(Dir));
HSSFWorkbook wb = new HSSFWorkbook(fs);
HSSFSheet sheet = wb.getSheetAt(0);
HSSFRow row;
HSSFCell cell;
int rows; // No of rows
rows = sheet.getPhysicalNumberOfRows();
int cols = 0; // No of columns
int tmp = 0;
int cblacks=0;
// This trick ensures that we get the data properly even if it doesn't start from first few rows
for(int i = 0; i <= 10 || i <= rows; i++) {
row = sheet.getRow(i);
if(row != null) {
tmp = sheet.getRow(i).getPhysicalNumberOfCells();
if(tmp >= cols) cols = tmp;else{rows++;cblacks++;}
}
cols++;
}
cols=cols+cblacks;
for(int r = 0; r < rows; r++) {
row = sheet.getRow(r);
if(row != null) {
for(int c = 0; c < cols; c++) {
cell = row.getCell(c);
if(cell != null) {
System.out.print(cell+"\n");//Your Code here
}
}
}
}} catch(Exception ioe) {
ioe.printStackTrace();}
If column number are varing you can use this
package com.org.tests;
import org.apache.poi.xssf.usermodel.*;
import java.io.FileInputStream;
import java.io.IOException;
public class ExcelSimpleTest
{
String path;
public FileInputStream fis = null;
private XSSFWorkbook workbook = null;
private XSSFSheet sheet = null;
private XSSFRow row =null;
private XSSFCell cell = null;
public ExcelSimpleTest() throws IOException
{
path = System.getProperty("user.dir")+"\\resources\\Book1.xlsx";
fis = new FileInputStream(path);
workbook = new XSSFWorkbook(fis);
sheet = workbook.getSheetAt(0);
}
public void ExelWorks()
{
int index = workbook.getSheetIndex("Sheet1");
sheet = workbook.getSheetAt(index);
int rownumber=sheet.getLastRowNum()+1;
for (int i=1; i<rownumber; i++ )
{
row = sheet.getRow(i);
int colnumber = row.getLastCellNum();
for (int j=0; j<colnumber; j++ )
{
cell = row.getCell(j);
System.out.println(cell.getStringCellValue());
}
}
}
public static void main(String[] args) throws IOException
{
ExcelSimpleTest excelwork = new ExcelSimpleTest();
excelwork.ExelWorks();
}
}
The corresponding mavendependency can be found here
Another way to read/write Excel files is to use Windmill. It provides a fluent API to process Excel and CSV files.
Import data
try (Stream<Row> rowStream = Windmill.parse(FileSource.of(new FileInputStream("myFile.xlsx")))) {
rowStream
// skip the header row that contains the column names
.skip(1)
.forEach(row -> {
System.out.println(
"row n°" + row.rowIndex()
+ " column 'User login' value : " + row.cell("User login").asString()
+ " column n°3 number value : " + row.cell(2).asDouble().value() // index is zero-based
);
});
}
Export data
Windmill
.export(Arrays.asList(bean1, bean2, bean3))
.withHeaderMapping(
new ExportHeaderMapping<Bean>()
.add("Name", Bean::getName)
.add("User login", bean -> bean.getUser().getLogin())
)
.asExcel()
.writeTo(new FileOutputStream("Export.xlsx"));
You need Apache POI library and this code below should help you
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Iterator;
//*************************************************************
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
//*************************************************************
public class AdvUse {
private static Workbook wb ;
private static Sheet sh ;
private static FileInputStream fis ;
private static FileOutputStream fos ;
private static Row row ;
private static Cell cell ;
private static String ExcelPath ;
//*************************************************************
public static void setEcxelFile(String ExcelPath, String SheetName) throws Exception {
try {
File f= new File(ExcelPath);
if(!f.exists()){
f.createNewFile();
System.out.println("File not Found so created");
}
fis = new FileInputStream("./testData.xlsx");
wb = WorkbookFactory.create(fis);
sh = wb.getSheet("SheetName");
if(sh == null){
sh = wb.getSheet(SheetName);
}
}catch(Exception e)
{System.out.println(e.getMessage());
}
}
//*************************************************************
public static void setCellData(String text , int rowno , int colno){
try{
row = sh.getRow(rowno);
if(row == null){
row = sh.createRow(rowno);
}
cell = row.getCell(colno);
if(cell!=null){
cell.setCellValue(text);
}
else{
cell = row.createCell(colno);
cell.setCellValue(text);
}
fos = new FileOutputStream(ExcelPath);
wb.write(fos);
fos.flush();
fos.close();
}catch(Exception e){
System.out.println(e.getMessage());
}
}
//*************************************************************
public static String getCellData(int rowno , int colno){
try{
cell = sh.getRow(rowno).getCell(colno);
String CellData = null ;
switch(cell.getCellType()){
case STRING :
CellData = cell.getStringCellValue();
break ;
case NUMERIC :
CellData = Double.toString(cell.getNumericCellValue());
if(CellData.contains(".o")){
CellData = CellData.substring(0,CellData.length()-2);
}
break ;
case BLANK :
CellData = ""; break ;
}
return CellData;
}catch(Exception e){return ""; }
}
//*************************************************************
public static int getLastRow(){
return sh.getLastRowNum();
}
You can not read & write same file in parallel(Read-write lock). But, we can do parallel operations on temporary data(i.e. Input/output stream). Write the data to file only after closing the input stream. Below steps should be followed.
Open the file to Input stream
Open the same file to an Output Stream
Read and do the processing
Write contents to output stream.
Close the read/input stream, close file
Close output stream, close file.
Apache POI - read/write same excel example
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.sql.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
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 XLSXReaderWriter {
public static void main(String[] args) {
try {
File excel = new File("D://raju.xlsx");
FileInputStream fis = new FileInputStream(excel);
XSSFWorkbook book = new XSSFWorkbook(fis);
XSSFSheet sheet = book.getSheetAt(0);
Iterator<Row> itr = sheet.iterator();
// Iterating over Excel file in Java
while (itr.hasNext()) {
Row row = itr.next();
// Iterating over each column of Excel file
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
switch (cell.getCellType()) {
case Cell.CELL_TYPE_STRING:
System.out.print(cell.getStringCellValue() + "\t");
break;
case Cell.CELL_TYPE_NUMERIC:
System.out.print(cell.getNumericCellValue() + "\t");
break;
case Cell.CELL_TYPE_BOOLEAN:
System.out.print(cell.getBooleanCellValue() + "\t");
break;
default:
}
}
System.out.println("");
}
// writing data into XLSX file
Map<String, Object[]> newData = new HashMap<String, Object[]>();
newData.put("1", new Object[] { 1d, "Raju", "75K", "dev",
"SGD" });
newData.put("2", new Object[] { 2d, "Ramesh", "58K", "test",
"USD" });
newData.put("3", new Object[] { 3d, "Ravi", "90K", "PMO",
"INR" });
Set<String> newRows = newData.keySet();
int rownum = sheet.getLastRowNum();
for (String key : newRows) {
Row row = sheet.createRow(rownum++);
Object[] objArr = newData.get(key);
int cellnum = 0;
for (Object obj : objArr) {
Cell cell = row.createCell(cellnum++);
if (obj instanceof String) {
cell.setCellValue((String) obj);
} else if (obj instanceof Boolean) {
cell.setCellValue((Boolean) obj);
} else if (obj instanceof Date) {
cell.setCellValue((Date) obj);
} else if (obj instanceof Double) {
cell.setCellValue((Double) obj);
}
}
}
// open an OutputStream to save written data into Excel file
FileOutputStream os = new FileOutputStream(excel);
book.write(os);
System.out.println("Writing on Excel file Finished ...");
// Close workbook, OutputStream and Excel file to prevent leak
os.close();
book.close();
fis.close();
} catch (FileNotFoundException fe) {
fe.printStackTrace();
} catch (IOException ie) {
ie.printStackTrace();
}
}
}
Please use Apache POI libs and try this.
try
{
FileInputStream x = new FileInputStream(new File("/Users/rajesh/Documents/rajesh.xls"));
//Create Workbook instance holding reference to .xlsx file
Workbook workbook = new HSSFWorkbook(x);
//Get first/desired sheet from the workbook
Sheet sheet = workbook.getSheetAt(0);
//Iterate through each rows one by one
for (Iterator<Row> iterator = sheet.iterator(); iterator.hasNext();) {
Row row = (Row) iterator.next();
for (Iterator<Cell> iterator2 = row.iterator(); iterator2
.hasNext();) {
Cell cell = (Cell) iterator2.next();
System.out.println(cell.getStringCellValue());
}
}
x.close();
}
catch (Exception e)
{
e.printStackTrace();
}
}
}
When using the apache poi 4.1.2. The celltype changes a bit. Below is an example
try {
File excel = new File("/home/name/Downloads/bb.xlsx");
FileInputStream fis = new FileInputStream(excel);
XSSFWorkbook book = new XSSFWorkbook(fis);
XSSFSheet sheet = book.getSheetAt(0);
Iterator<Row> itr = sheet.iterator();
// Iterating over Excel file in Java
while (itr.hasNext()) {
Row row = itr.next();
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
switch (cell.getCellType()) {
case STRING:
System.out.print(cell.getStringCellValue() + "\t");
break;
case NUMERIC:
System.out.print(cell.getNumericCellValue() + "\t");
break;
case BOOLEAN:
System.out.print(cell.getBooleanCellValue() + "\t");
break;
default:
}
}
System.out.println("");}
}catch (Exception e) {
// TODO: handle exception
e.printStackTrace();
}
If you go for third party library option, try using Aspose.Cells API that enables Java Applications to create (read/write) and manage Excel spreadsheets efficiently without requiring Microsoft Excel.
e.g
Sample code:
1.
//Load sample workbook
Workbook wb = new Workbook(dirPath + "sample.xlsx");
//Access first worksheet
Worksheet ws = wb.getWorksheets().get(0);
//Access cells iterator
Iterator itrat = ws.getCells().iterator();
//Print cells name in iterator
while(itrat.hasNext())
{
Cell cell = (Cell)itrat.next();
System.out.println(cell.getName() + ": " + cell.getStringValue().trim());
}
Workbook book = new Workbook("sample.xlsx");
Worksheet sheet = book.getWorksheets().get(0);
Range range = sheet.getCells().getMaxDisplayRange();//You may also create your desired range (in the worksheet) using, e.g sheet.getCells().createRange("A1", "J11");
Iterator rangeIterator = range.iterator();
while(rangeIterator.hasNext())
{
Cell cell = (Cell)rangeIterator.next();
//your code goes here.
}
Hope, this helps a bit.
PS. I am working as Support developer/ Evangelist at Aspose.
If you need to do anything more with office documents in Java, go for POI as mentioned.
For simple reading/writing an excel document like you requested, you can use the CSV format (also as mentioned):
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Scanner;
public class CsvWriter {
public static void main(String args[]) throws IOException {
String fileName = "test.xls";
PrintWriter out = new PrintWriter(new FileWriter(fileName));
out.println("a,b,c,d");
out.println("e,f,g,h");
out.println("i,j,k,l");
out.close();
BufferedReader in = new BufferedReader(new FileReader(fileName));
String line = null;
while ((line = in.readLine()) != null) {
Scanner scanner = new Scanner(line);
String sep = "";
while (scanner.hasNext()) {
System.out.println(sep + scanner.next());
sep = ",";
}
}
in.close();
}
}
This will write a JTable to a tab separated file that can be easily imported into Excel. This works.
If you save an Excel worksheet as an XML document you could also build the XML file for EXCEL with code. I have done this with word so you do not have to use third-party packages.
This could code have the JTable taken out and then just write a tab separated to any text file and then import into Excel. I hope this helps.
Code:
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import javax.swing.JTable;
import javax.swing.table.TableModel;
public class excel {
String columnNames[] = { "Column 1", "Column 2", "Column 3" };
// Create some data
String dataValues[][] =
{
{ "12", "234", "67" },
{ "-123", "43", "853" },
{ "93", "89.2", "109" },
{ "279", "9033", "3092" }
};
JTable table;
excel() {
table = new JTable( dataValues, columnNames );
}
public void toExcel(JTable table, File file){
try{
TableModel model = table.getModel();
FileWriter excel = new FileWriter(file);
for(int i = 0; i < model.getColumnCount(); i++){
excel.write(model.getColumnName(i) + "\t");
}
excel.write("\n");
for(int i=0; i< model.getRowCount(); i++) {
for(int j=0; j < model.getColumnCount(); j++) {
excel.write(model.getValueAt(i,j).toString()+"\t");
}
excel.write("\n");
}
excel.close();
}catch(IOException e){ System.out.println(e); }
}
public static void main(String[] o) {
excel cv = new excel();
cv.toExcel(cv.table,new File("C:\\Users\\itpr13266\\Desktop\\cs.tbv"));
}
}

Iteration error in Excel sheet

When I tried to select items from the item list using Excel sheet through Java environment, only the first item is selected and executed. The next set of iteration is not happening.
int i=1;
while (i<=sheet.getLastRowNum() )
{
row = sheet.getRow(i);
String w = row.getCell(0).getStringCellValue();
// Processing : logic on "items" from excel
i++;
}
OK then try this sample firstly before your code. Check every column and row is visited. Maybe better way is using Iterators.
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();
}

Covert XLSX row into string and add to array

I am trying to get a basic java program to read from a xlsx file and put each row into an arrayList as a string, where later on I will then split that String up of that row.
Below is my code, however i'm trying to figure out where I have gone wrong as it doesn't appear to be doing anything.
List<String> text = new ArrayList<String>();
Workbook wb = WorkbookFactory.create(new File("input.xlsx"));
DataFormatter fmt = new DataFormatter();
Sheet s = wb.getSheetAt(0);
for (Row r : s) {
StringBuffer sb = new StringBuffer();
for (Cell c : r) {
if (sb.length() > 0) sb.append(" - ");
sb.append(fmt.formatCell(c));
}
text.append(sb.toString());
}
Any help would be appreciated.
You are not reading any cell. See this example:
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFSheet;
//..
FileInputStream file = new FileInputStream(new File("C:\\test.xlsx"));
//Get the workbook instance for XLS file
XSSFWorkbook workbook = new XSSFWorkbook (file);
//Get first sheet from the workbook
XSSFSheet 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();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

java converting .xls to csv

I have converted to .xls file to a csv file using the Apache POI library. I iterate each row and cell, put a comma, and append to the buffered reader. The cell types numeric and string are converted perfectly. If a blank cell comes I put a comma, but blank values are not detected by the code. How to do it? Please help me out.
import java.io.*;
import java.util.Iterator;
import java.text.DateFormat;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.math.BigDecimal;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
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;
import org.apache.poi.xssf.usermodel.XSSFRichTextString;
import org.apache.poi.hssf.usermodel.HSSFDateUtil;
import org.apache.poi.ss.usermodel.DateUtil;
class convert {
static void convertToXls(File inputFile, File outputFile)
{
StringBuffer cellDData = new StringBuffer();
String cellDDataString=null;
try
{
FileOutputStream fos = new FileOutputStream(outputFile);
HSSFWorkbook workbook = new HSSFWorkbook(new FileInputStream(inputFile));
HSSFSheet sheet = workbook.getSheetAt(0);
Cell cell=null;
Row row;
int previousCell;
int currentCell;
Iterator<Row> rowIterator = sheet.iterator();
while (rowIterator.hasNext())
{
previousCell = -1;
currentCell = 0;
row = rowIterator.next();
System.out.println("ROW:-->");
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext())
{
// System.out.println("true" +cellIterator.hasNext());
cell = cellIterator.next();
currentCell = cell.getColumnIndex();
System.out.println("CELL:-->" +cell.toString());
try{
switch (cell.getCellType())
{
case Cell.CELL_TYPE_BOOLEAN:
cellDData.append(cell.getBooleanCellValue() + ",");
System.out.println("boo"+ cell.getBooleanCellValue());
break;
case Cell.CELL_TYPE_NUMERIC:
if (DateUtil.isCellDateFormatted(cell))
{
// System.out.println(cell.getDateCellValue());
SimpleDateFormat dateFormat = new SimpleDateFormat(
"dd/MM/yyyy");
String strCellValue = dateFormat.format(cell.getDateCellValue());
// System.out.println("date:"+strCellValue);
cellDData.append(strCellValue +",");
}
else {
System.out.println(cell.getNumericCellValue());
Double value = cell.getNumericCellValue();
Long longValue = value.longValue();
String strCellValue1 = new String(longValue.toString());
// System.out.println("number:"+strCellValue1);
cellDData.append(strCellValue1 +",");
}
// cellDData.append(cell.getNumericCellValue() + ",");
//String i=(new java.text.DecimalFormat("0").format( cell.getNumericCellValue()+"," ));
//System.out.println("number"+cell.getNumericCellValue());
break;
case Cell.CELL_TYPE_STRING:
String out=cell.getRichStringCellValue().getString();
cellDData.append(cell.getRichStringCellValue().getString() + ",");
//System.out.println("string"+cell.getStringCellValue());
break;
case Cell.CELL_TYPE_BLANK:
cellDData.append("" + "THIS IS BLANK");
System.out.print("THIS IS BLANK");
break;
default:
break;
}}
catch (NullPointerException e) {
//do something clever with the exception
System.out.println("nullException"+e.getMessage());
}
}
int len=cellDData.length() - 1;
// System.out.println("length:"+len);
// System.out.println("length1:"+cellDData.length());
cellDData.replace(cellDData.length() - 1, cellDData.length() , "");
cellDData.append("\n");
}
//cellDData.append("\n");
//String out=cellDData.toString();
//System.out.println("res"+out);
//String o = out.substring(0, out.lastIndexOf(","));
//System.out.println("final"+o);
fos.write(cellDData.toString().getBytes());
//fos.write(cellDDataString.getBytes());
fos.close();
}
catch (FileNotFoundException e)
{
System.err.println("Exception" + e.getMessage());
}
catch (IOException e)
{
System.err.println("Exception" + e.getMessage());
}
}
public static void main(String[] args) throws IOException
{
File inputFile = new File("/bwdev/kadfeb/xls/Accredo_Kadmon_Monthly_02282014.xls");
File outputFile = new File("output1.csv");
convertToXls(inputFile, outputFile);
}
I assume that the HSSFWorkbook by default skips the blank cells or missing cells. Try setting the MissingCellPolicy for the HSSFWorkbook object.
The possible values to be set for MissingCellPolicy can be found here
Use row index and col index instead of Iterator.
HSSFWorkbook workbook = new HSSFWorkbook(new FileInputStream(inputFile));
workbook.setMissingCellPolicy(Row.CREATE_NULL_AS_BLANK);
HSSFSheet sheet = workbook.getSheetAt(0);
for(int rowIndex = sheet.getFirstRowNum(); rowIndex < sheet.getLastRowNum(); rowIndex++)
{
Cell cell=null;
Row row = null;
previousCell = -1;
currentCell = 0;
row = sheet.getRow(rowIndex);
for(int colIndex=row.getFirstCellNum(); colIndex < row.getLastCellNum(); colIndex++)
{
cell = row.getCell(colIndex);
currentCell = cell.getColumnIndex();
/* Cell processing starts here*/
}
}
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.Iterator;
import org.apache.commons.io.FilenameUtils;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
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 XlsxtoCSV {
static void xlsx(File inputFile, File outputFile) {
// For storing data into CSV files
StringBuffer data = new StringBuffer();
try {
FileOutputStream fos = new FileOutputStream(outputFile);
// Get the workbook object for XLSX file
FileInputStream fis = new FileInputStream(inputFile);
Workbook workbook = null;
String ext = FilenameUtils.getExtension(inputFile.toString());
if (ext.equalsIgnoreCase("xlsx")) {
workbook = new XSSFWorkbook(fis);
} else if (ext.equalsIgnoreCase("xls")) {
workbook = new HSSFWorkbook(fis);
}
// Get first sheet from the workbook
int numberOfSheets = workbook.getNumberOfSheets();
Row row;
Cell cell;
// Iterate through each rows from first sheet
for (int i = 0; i < numberOfSheets; i++) {
Sheet sheet = workbook.getSheetAt(0);
Iterator<Row> rowIterator = sheet.iterator();
while (rowIterator.hasNext()) {
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'); // appending new line after each row
}
}
fos.write(data.toString().getBytes());
fos.close();
} catch (Exception ioe) {
ioe.printStackTrace();
}
}
// testing the application
public static void main(String[] args) {
// int i=0;
// reading file from desktop
File inputFile = new File(".//src//test//resources//yourExcel.xls"); //provide your path
// writing excel data to csv
File outputFile = new File(".//src//test//resources//yourCSV.csv"); //provide your path
xlsx(inputFile, outputFile);
System.out.println("Conversion of " + inputFile + " to flat file: "
+ outputFile + " is completed");
}
}
I replaced
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
with
for (int cn = 0; cn < row.getLastCellNum(); cn++) {
Cell cell = row.getCell(cn, Row.CREATE_NULL_AS_BLANK);
Simple way to convert xls/xlsx into csv by using apache POI.
public class XLSXToCSVConverter {
public InputStream convertxlstoCSV(InputStream inputStream) throws IOException, InvalidFormatException {
Workbook wb = WorkbookFactory.create(inputStream);
return csvConverter(wb.getSheetAt(0));
}
private InputStream csvConverter(Sheet sheet) {
Row row = null;
String str = new String();
for (int i = 0; i < sheet.getLastRowNum()+1; i++) {
row = sheet.getRow(i);
String rowString = new String();
for (int j = 0; j < 3; j++) {
if(row.getCell(j)==null) {
rowString = rowString + Utility.BLANK_SPACE + Utility.COMMA;
}
else {
rowString = rowString + row.getCell(j)+ Utility.COMMA;
}
}
str = str + rowString.substring(0,rowString.length()-1)+ Utility.NEXT_LINE_OPERATOR;
}
System.out.println(str);
return new ByteArrayInputStream(str.getBytes(StandardCharsets.UTF_8));
}
}
I suggest this one. It is very similiar to previos ones, but have for loop instead of iterator, whick gives you oportunity not to skip empty (deleted) cells
public InputStream fromExcelToCsv(Sheet sheet, String delimiter) throws IOException {
// For storing data into CSV files
StringBuilder data = new StringBuilder();
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
Row row;
// Iterate through each rows from first sheet
Iterator<Row> rowIterator = sheet.iterator();
while (rowIterator.hasNext()) {
row = rowIterator.next();
for (int i = row.getFirstCellNum(); i < row.getLastCellNum(); i++) {
Cell cell = row.getCell(i);
if (cell == null) {
//cell is deletd => add empty
data.append(delimiter);
} else {
switch (cell.getCellTypeEnum()) {
case BOOLEAN:
data.append(cell.getBooleanCellValue()).append(delimiter);
break;
case NUMERIC:
double numericCellValue = cell.getNumericCellValue();
//All numbers in excel is double. example: 1.0
//If there is no
fractional part than delete it
if (numericCellValue % 1 == 0) {
data.append((int) numericCellValue).append(delimiter);
} else {
data.append(numericCellValue).append(delimiter);
}
break;
case STRING:
data.append(cell.getStringCellValue()).append(delimiter);
break;
case BLANK:
data.append(delimiter);
break;
default:
data.append(cell).append(delimiter);
}
}
}
data.append('\n'); // appending new line after each row
}
byteArrayOutputStream.write(data.toString().getBytes());
byteArrayOutputStream.close();
return new ByteArrayInputStream(byteArrayOutputStream.toByteArray());
}

How to read and write excel file

I want to read and write an Excel file from Java with 3 columns and N rows, printing one string in each cell. Can anyone give me simple code snippet for this? Do I need to use any external lib or does Java have built-in support for it?
I want to do the following:
for(i=0; i <rows; i++)
//read [i,col1] ,[i,col2], [i,col3]
for(i=0; i<rows; i++)
//write [i,col1], [i,col2], [i,col3]
Try the Apache POI HSSF. Here's an example on how to read an excel file:
try {
POIFSFileSystem fs = new POIFSFileSystem(new FileInputStream(file));
HSSFWorkbook wb = new HSSFWorkbook(fs);
HSSFSheet sheet = wb.getSheetAt(0);
HSSFRow row;
HSSFCell cell;
int rows; // No of rows
rows = sheet.getPhysicalNumberOfRows();
int cols = 0; // No of columns
int tmp = 0;
// This trick ensures that we get the data properly even if it doesn't start from first few rows
for(int i = 0; i < 10 || i < rows; i++) {
row = sheet.getRow(i);
if(row != null) {
tmp = sheet.getRow(i).getPhysicalNumberOfCells();
if(tmp > cols) cols = tmp;
}
}
for(int r = 0; r < rows; r++) {
row = sheet.getRow(r);
if(row != null) {
for(int c = 0; c < cols; c++) {
cell = row.getCell((short)c);
if(cell != null) {
// Your code here
}
}
}
}
} catch(Exception ioe) {
ioe.printStackTrace();
}
On the documentation page you also have examples of how to write to excel files.
Apache POI can do this for you. Specifically the HSSF module. The quick guide is most useful. Here's how to do what you want - specifically create a sheet and write it out.
Workbook wb = new HSSFWorkbook();
//Workbook wb = new XSSFWorkbook();
CreationHelper createHelper = wb.getCreationHelper();
Sheet sheet = wb.createSheet("new sheet");
// Create a row and put some cells in it. Rows are 0 based.
Row row = sheet.createRow((short)0);
// Create a cell and put a value in it.
Cell cell = row.createCell(0);
cell.setCellValue(1);
// Or do it on one line.
row.createCell(1).setCellValue(1.2);
row.createCell(2).setCellValue(
createHelper.createRichTextString("This is a string"));
row.createCell(3).setCellValue(true);
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("workbook.xls");
wb.write(fileOut);
fileOut.close();
First add all these jar files in your project class path:
poi-scratchpad-3.7-20101029
poi-3.2-FINAL-20081019
poi-3.7-20101029
poi-examples-3.7-20101029
poi-ooxml-3.7-20101029
poi-ooxml-schemas-3.7-20101029
xmlbeans-2.3.0
dom4j-1.6.1
Code for writing in a excel file:
public static void main(String[] args) {
//Blank workbook
XSSFWorkbook workbook = new XSSFWorkbook();
//Create a blank sheet
XSSFSheet sheet = workbook.createSheet("Employee Data");
//This data needs to be written (Object[])
Map<String, Object[]> data = new TreeMap<String, Object[]>();
data.put("1", new Object[]{"ID", "NAME", "LASTNAME"});
data.put("2", new Object[]{1, "Amit", "Shukla"});
data.put("3", new Object[]{2, "Lokesh", "Gupta"});
data.put("4", new Object[]{3, "John", "Adwards"});
data.put("5", new Object[]{4, "Brian", "Schultz"});
//Iterate over data and write to sheet
Set<String> keyset = data.keySet();
int rownum = 0;
for (String key : keyset)
{
//create a row of excelsheet
Row row = sheet.createRow(rownum++);
//get object array of prerticuler key
Object[] objArr = data.get(key);
int cellnum = 0;
for (Object obj : objArr)
{
Cell cell = row.createCell(cellnum++);
if (obj instanceof String)
{
cell.setCellValue((String) obj);
}
else if (obj instanceof Integer)
{
cell.setCellValue((Integer) obj);
}
}
}
try
{
//Write the workbook in file system
FileOutputStream out = new FileOutputStream(new File("C:\\Documents and Settings\\admin\\Desktop\\imp data\\howtodoinjava_demo.xlsx"));
workbook.write(out);
out.close();
System.out.println("howtodoinjava_demo.xlsx written successfully on disk.");
}
catch (Exception e)
{
e.printStackTrace();
}
}
Code for reading from excel file
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
public static void main(String[] args) {
try {
FileInputStream file = new FileInputStream(new File("C:\\Documents and Settings\\admin\\Desktop\\imp data\\howtodoinjava_demo.xlsx"));
//Create Workbook instance holding reference to .xlsx file
XSSFWorkbook workbook = new XSSFWorkbook(file);
//Get first/desired sheet from the workbook
XSSFSheet sheet = workbook.getSheetAt(0);
//Iterate through each rows one by one
Iterator<Row> rowIterator = sheet.iterator();
while (rowIterator.hasNext())
{
Row row = rowIterator.next();
//For each row, iterate through all the columns
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext())
{
Cell cell = cellIterator.next();
//Check the cell type and format accordingly
switch (cell.getCellType())
{
case Cell.CELL_TYPE_NUMERIC:
System.out.print(cell.getNumericCellValue() + "\t");
break;
case Cell.CELL_TYPE_STRING:
System.out.print(cell.getStringCellValue() + "\t");
break;
}
}
System.out.println("");
}
file.close();
} catch (Exception e) {
e.printStackTrace();
}
}
You can also consider JExcelApi. I find it better designed than POI. There's a tutorial here.
There is a new easy and very cool tool (10x to Kfir): xcelite
Write:
public class User {
#Column (name="Firstname")
private String firstName;
#Column (name="Lastname")
private String lastName;
#Column
private long id;
#Column
private Date birthDate;
}
Xcelite xcelite = new Xcelite();
XceliteSheet sheet = xcelite.createSheet("users");
SheetWriter<User> writer = sheet.getBeanWriter(User.class);
List<User> users = new ArrayList<User>();
// ...fill up users
writer.write(users);
xcelite.write(new File("users_doc.xlsx"));
Read:
Xcelite xcelite = new Xcelite(new File("users_doc.xlsx"));
XceliteSheet sheet = xcelite.getSheet("users");
SheetReader<User> reader = sheet.getBeanReader(User.class);
Collection<User> users = reader.read();
For reading a xlsx file we can use Apache POI libs
Try this:
public static void readXLSXFile() throws IOException
{
InputStream ExcelFileToRead = new FileInputStream("C:/Test.xlsx");
XSSFWorkbook wb = new XSSFWorkbook(ExcelFileToRead);
XSSFWorkbook test = new XSSFWorkbook();
XSSFSheet sheet = wb.getSheetAt(0);
XSSFRow row;
XSSFCell cell;
Iterator rows = sheet.rowIterator();
while (rows.hasNext())
{
row=(XSSFRow) rows.next();
Iterator cells = row.cellIterator();
while (cells.hasNext())
{
cell=(XSSFCell) cells.next();
if (cell.getCellType() == XSSFCell.CELL_TYPE_STRING)
{
System.out.print(cell.getStringCellValue()+" ");
}
else if(cell.getCellType() == XSSFCell.CELL_TYPE_NUMERIC)
{
System.out.print(cell.getNumericCellValue()+" ");
}
else
{
//U Can Handel Boolean, Formula, Errors
}
}
System.out.println();
}
}
.csv or POI will certainly do it, but you should be aware of Andy Khan's JExcel. I think it's by far the best Java library for working with Excel there is.
A simple CSV file should suffice
String path="C:\\Book2.xlsx";
try {
File f = new File( path );
Workbook wb = WorkbookFactory.create(f);
Sheet mySheet = wb.getSheetAt(0);
Iterator<Row> rowIter = mySheet.rowIterator();
for ( Iterator<Row> rowIterator = mySheet.rowIterator() ;rowIterator.hasNext(); )
{
for ( Iterator<Cell> cellIterator = ((Row)rowIterator.next()).cellIterator() ; cellIterator.hasNext() ; )
{
System.out.println ( ( (Cell)cellIterator.next() ).toString() );
}
System.out.println( " **************************************************************** ");
}
} catch ( Exception e )
{
System.out.println( "exception" );
e.printStackTrace();
}
and make sure to have added the jars poi and poi-ooxml (org.apache.poi) to your project
For reading data from .xlsx workbooks we need to use XSSFworkbook classes.
XSSFWorkbook xlsxBook = new XSSFWorkbook(fis);
XSSFSheet sheet = xlsxBook.getSheetAt(0); etc.
We need to use Apache-poi 3.9 # http://poi.apache.org/
For detailed info with example visit
: http://java-recent.blogspot.in
Sure , you will find the code below useful and easy to read and write. This is a util class which you can use in your main method and then you are good to use all methods below.
public class ExcelUtils {
private static XSSFSheet ExcelWSheet;
private static XSSFWorkbook ExcelWBook;
private static XSSFCell Cell;
private static XSSFRow Row;
File fileName = new File("C:\\Users\\satekuma\\Pro\\Fund.xlsx");
public void setExcelFile(File Path, String SheetName) throws Exception
try {
FileInputStream ExcelFile = new FileInputStream(Path);
ExcelWBook = new XSSFWorkbook(ExcelFile);
ExcelWSheet = ExcelWBook.getSheet(SheetName);
} catch (Exception e) {
throw (e);
}
}
public static String getCellData(int RowNum, int ColNum) throws Exception {
try {
Cell = ExcelWSheet.getRow(RowNum).getCell(ColNum);
String CellData = Cell.getStringCellValue();
return CellData;
} catch (Exception e) {
return "";
}
}
public static void setCellData(String Result, int RowNum, int ColNum, File Path) throws Exception {
try {
Row = ExcelWSheet.createRow(RowNum - 1);
Cell = Row.createCell(ColNum - 1);
Cell.setCellValue(Result);
FileOutputStream fileOut = new FileOutputStream(Path);
ExcelWBook.write(fileOut);
fileOut.flush();
fileOut.close();
} catch (Exception e) {
throw (e);
}
}
}
using spring apache poi repo
if (fileName.endsWith(".xls")) {
File myFile = new File("file location" + fileName);
FileInputStream fis = new FileInputStream(myFile);
org.apache.poi.ss.usermodel.Workbook workbook = null;
try {
workbook = WorkbookFactory.create(fis);
} catch (InvalidFormatException e) {
e.printStackTrace();
}
org.apache.poi.ss.usermodel.Sheet sheet = workbook.getSheetAt(0);
Iterator<Row> rowIterator = sheet.iterator();
while (rowIterator.hasNext()) {
Row row = rowIterator.next();
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
switch (cell.getCellType()) {
case Cell.CELL_TYPE_STRING:
System.out.print(cell.getStringCellValue());
break;
case Cell.CELL_TYPE_BOOLEAN:
System.out.print(cell.getBooleanCellValue());
break;
case Cell.CELL_TYPE_NUMERIC:
System.out.print(cell.getNumericCellValue());
break;
}
System.out.print(" - ");
}
System.out.println();
}
}
I edited the most voted one a little cuz it didn't count blanks columns or rows well not totally, so here is my code i tested it and now can get any cell in any part of an excel file. also now u can have blanks columns between filled column and it will read them
try {
POIFSFileSystem fs = new POIFSFileSystem(new FileInputStream(Dir));
HSSFWorkbook wb = new HSSFWorkbook(fs);
HSSFSheet sheet = wb.getSheetAt(0);
HSSFRow row;
HSSFCell cell;
int rows; // No of rows
rows = sheet.getPhysicalNumberOfRows();
int cols = 0; // No of columns
int tmp = 0;
int cblacks=0;
// This trick ensures that we get the data properly even if it doesn't start from first few rows
for(int i = 0; i <= 10 || i <= rows; i++) {
row = sheet.getRow(i);
if(row != null) {
tmp = sheet.getRow(i).getPhysicalNumberOfCells();
if(tmp >= cols) cols = tmp;else{rows++;cblacks++;}
}
cols++;
}
cols=cols+cblacks;
for(int r = 0; r < rows; r++) {
row = sheet.getRow(r);
if(row != null) {
for(int c = 0; c < cols; c++) {
cell = row.getCell(c);
if(cell != null) {
System.out.print(cell+"\n");//Your Code here
}
}
}
}} catch(Exception ioe) {
ioe.printStackTrace();}
If column number are varing you can use this
package com.org.tests;
import org.apache.poi.xssf.usermodel.*;
import java.io.FileInputStream;
import java.io.IOException;
public class ExcelSimpleTest
{
String path;
public FileInputStream fis = null;
private XSSFWorkbook workbook = null;
private XSSFSheet sheet = null;
private XSSFRow row =null;
private XSSFCell cell = null;
public ExcelSimpleTest() throws IOException
{
path = System.getProperty("user.dir")+"\\resources\\Book1.xlsx";
fis = new FileInputStream(path);
workbook = new XSSFWorkbook(fis);
sheet = workbook.getSheetAt(0);
}
public void ExelWorks()
{
int index = workbook.getSheetIndex("Sheet1");
sheet = workbook.getSheetAt(index);
int rownumber=sheet.getLastRowNum()+1;
for (int i=1; i<rownumber; i++ )
{
row = sheet.getRow(i);
int colnumber = row.getLastCellNum();
for (int j=0; j<colnumber; j++ )
{
cell = row.getCell(j);
System.out.println(cell.getStringCellValue());
}
}
}
public static void main(String[] args) throws IOException
{
ExcelSimpleTest excelwork = new ExcelSimpleTest();
excelwork.ExelWorks();
}
}
The corresponding mavendependency can be found here
Another way to read/write Excel files is to use Windmill. It provides a fluent API to process Excel and CSV files.
Import data
try (Stream<Row> rowStream = Windmill.parse(FileSource.of(new FileInputStream("myFile.xlsx")))) {
rowStream
// skip the header row that contains the column names
.skip(1)
.forEach(row -> {
System.out.println(
"row n°" + row.rowIndex()
+ " column 'User login' value : " + row.cell("User login").asString()
+ " column n°3 number value : " + row.cell(2).asDouble().value() // index is zero-based
);
});
}
Export data
Windmill
.export(Arrays.asList(bean1, bean2, bean3))
.withHeaderMapping(
new ExportHeaderMapping<Bean>()
.add("Name", Bean::getName)
.add("User login", bean -> bean.getUser().getLogin())
)
.asExcel()
.writeTo(new FileOutputStream("Export.xlsx"));
You need Apache POI library and this code below should help you
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Iterator;
//*************************************************************
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
//*************************************************************
public class AdvUse {
private static Workbook wb ;
private static Sheet sh ;
private static FileInputStream fis ;
private static FileOutputStream fos ;
private static Row row ;
private static Cell cell ;
private static String ExcelPath ;
//*************************************************************
public static void setEcxelFile(String ExcelPath, String SheetName) throws Exception {
try {
File f= new File(ExcelPath);
if(!f.exists()){
f.createNewFile();
System.out.println("File not Found so created");
}
fis = new FileInputStream("./testData.xlsx");
wb = WorkbookFactory.create(fis);
sh = wb.getSheet("SheetName");
if(sh == null){
sh = wb.getSheet(SheetName);
}
}catch(Exception e)
{System.out.println(e.getMessage());
}
}
//*************************************************************
public static void setCellData(String text , int rowno , int colno){
try{
row = sh.getRow(rowno);
if(row == null){
row = sh.createRow(rowno);
}
cell = row.getCell(colno);
if(cell!=null){
cell.setCellValue(text);
}
else{
cell = row.createCell(colno);
cell.setCellValue(text);
}
fos = new FileOutputStream(ExcelPath);
wb.write(fos);
fos.flush();
fos.close();
}catch(Exception e){
System.out.println(e.getMessage());
}
}
//*************************************************************
public static String getCellData(int rowno , int colno){
try{
cell = sh.getRow(rowno).getCell(colno);
String CellData = null ;
switch(cell.getCellType()){
case STRING :
CellData = cell.getStringCellValue();
break ;
case NUMERIC :
CellData = Double.toString(cell.getNumericCellValue());
if(CellData.contains(".o")){
CellData = CellData.substring(0,CellData.length()-2);
}
break ;
case BLANK :
CellData = ""; break ;
}
return CellData;
}catch(Exception e){return ""; }
}
//*************************************************************
public static int getLastRow(){
return sh.getLastRowNum();
}
You can not read & write same file in parallel(Read-write lock). But, we can do parallel operations on temporary data(i.e. Input/output stream). Write the data to file only after closing the input stream. Below steps should be followed.
Open the file to Input stream
Open the same file to an Output Stream
Read and do the processing
Write contents to output stream.
Close the read/input stream, close file
Close output stream, close file.
Apache POI - read/write same excel example
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.sql.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
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 XLSXReaderWriter {
public static void main(String[] args) {
try {
File excel = new File("D://raju.xlsx");
FileInputStream fis = new FileInputStream(excel);
XSSFWorkbook book = new XSSFWorkbook(fis);
XSSFSheet sheet = book.getSheetAt(0);
Iterator<Row> itr = sheet.iterator();
// Iterating over Excel file in Java
while (itr.hasNext()) {
Row row = itr.next();
// Iterating over each column of Excel file
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
switch (cell.getCellType()) {
case Cell.CELL_TYPE_STRING:
System.out.print(cell.getStringCellValue() + "\t");
break;
case Cell.CELL_TYPE_NUMERIC:
System.out.print(cell.getNumericCellValue() + "\t");
break;
case Cell.CELL_TYPE_BOOLEAN:
System.out.print(cell.getBooleanCellValue() + "\t");
break;
default:
}
}
System.out.println("");
}
// writing data into XLSX file
Map<String, Object[]> newData = new HashMap<String, Object[]>();
newData.put("1", new Object[] { 1d, "Raju", "75K", "dev",
"SGD" });
newData.put("2", new Object[] { 2d, "Ramesh", "58K", "test",
"USD" });
newData.put("3", new Object[] { 3d, "Ravi", "90K", "PMO",
"INR" });
Set<String> newRows = newData.keySet();
int rownum = sheet.getLastRowNum();
for (String key : newRows) {
Row row = sheet.createRow(rownum++);
Object[] objArr = newData.get(key);
int cellnum = 0;
for (Object obj : objArr) {
Cell cell = row.createCell(cellnum++);
if (obj instanceof String) {
cell.setCellValue((String) obj);
} else if (obj instanceof Boolean) {
cell.setCellValue((Boolean) obj);
} else if (obj instanceof Date) {
cell.setCellValue((Date) obj);
} else if (obj instanceof Double) {
cell.setCellValue((Double) obj);
}
}
}
// open an OutputStream to save written data into Excel file
FileOutputStream os = new FileOutputStream(excel);
book.write(os);
System.out.println("Writing on Excel file Finished ...");
// Close workbook, OutputStream and Excel file to prevent leak
os.close();
book.close();
fis.close();
} catch (FileNotFoundException fe) {
fe.printStackTrace();
} catch (IOException ie) {
ie.printStackTrace();
}
}
}
Please use Apache POI libs and try this.
try
{
FileInputStream x = new FileInputStream(new File("/Users/rajesh/Documents/rajesh.xls"));
//Create Workbook instance holding reference to .xlsx file
Workbook workbook = new HSSFWorkbook(x);
//Get first/desired sheet from the workbook
Sheet sheet = workbook.getSheetAt(0);
//Iterate through each rows one by one
for (Iterator<Row> iterator = sheet.iterator(); iterator.hasNext();) {
Row row = (Row) iterator.next();
for (Iterator<Cell> iterator2 = row.iterator(); iterator2
.hasNext();) {
Cell cell = (Cell) iterator2.next();
System.out.println(cell.getStringCellValue());
}
}
x.close();
}
catch (Exception e)
{
e.printStackTrace();
}
}
}
When using the apache poi 4.1.2. The celltype changes a bit. Below is an example
try {
File excel = new File("/home/name/Downloads/bb.xlsx");
FileInputStream fis = new FileInputStream(excel);
XSSFWorkbook book = new XSSFWorkbook(fis);
XSSFSheet sheet = book.getSheetAt(0);
Iterator<Row> itr = sheet.iterator();
// Iterating over Excel file in Java
while (itr.hasNext()) {
Row row = itr.next();
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
switch (cell.getCellType()) {
case STRING:
System.out.print(cell.getStringCellValue() + "\t");
break;
case NUMERIC:
System.out.print(cell.getNumericCellValue() + "\t");
break;
case BOOLEAN:
System.out.print(cell.getBooleanCellValue() + "\t");
break;
default:
}
}
System.out.println("");}
}catch (Exception e) {
// TODO: handle exception
e.printStackTrace();
}
If you go for third party library option, try using Aspose.Cells API that enables Java Applications to create (read/write) and manage Excel spreadsheets efficiently without requiring Microsoft Excel.
e.g
Sample code:
1.
//Load sample workbook
Workbook wb = new Workbook(dirPath + "sample.xlsx");
//Access first worksheet
Worksheet ws = wb.getWorksheets().get(0);
//Access cells iterator
Iterator itrat = ws.getCells().iterator();
//Print cells name in iterator
while(itrat.hasNext())
{
Cell cell = (Cell)itrat.next();
System.out.println(cell.getName() + ": " + cell.getStringValue().trim());
}
Workbook book = new Workbook("sample.xlsx");
Worksheet sheet = book.getWorksheets().get(0);
Range range = sheet.getCells().getMaxDisplayRange();//You may also create your desired range (in the worksheet) using, e.g sheet.getCells().createRange("A1", "J11");
Iterator rangeIterator = range.iterator();
while(rangeIterator.hasNext())
{
Cell cell = (Cell)rangeIterator.next();
//your code goes here.
}
Hope, this helps a bit.
PS. I am working as Support developer/ Evangelist at Aspose.
If you need to do anything more with office documents in Java, go for POI as mentioned.
For simple reading/writing an excel document like you requested, you can use the CSV format (also as mentioned):
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Scanner;
public class CsvWriter {
public static void main(String args[]) throws IOException {
String fileName = "test.xls";
PrintWriter out = new PrintWriter(new FileWriter(fileName));
out.println("a,b,c,d");
out.println("e,f,g,h");
out.println("i,j,k,l");
out.close();
BufferedReader in = new BufferedReader(new FileReader(fileName));
String line = null;
while ((line = in.readLine()) != null) {
Scanner scanner = new Scanner(line);
String sep = "";
while (scanner.hasNext()) {
System.out.println(sep + scanner.next());
sep = ",";
}
}
in.close();
}
}
This will write a JTable to a tab separated file that can be easily imported into Excel. This works.
If you save an Excel worksheet as an XML document you could also build the XML file for EXCEL with code. I have done this with word so you do not have to use third-party packages.
This could code have the JTable taken out and then just write a tab separated to any text file and then import into Excel. I hope this helps.
Code:
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import javax.swing.JTable;
import javax.swing.table.TableModel;
public class excel {
String columnNames[] = { "Column 1", "Column 2", "Column 3" };
// Create some data
String dataValues[][] =
{
{ "12", "234", "67" },
{ "-123", "43", "853" },
{ "93", "89.2", "109" },
{ "279", "9033", "3092" }
};
JTable table;
excel() {
table = new JTable( dataValues, columnNames );
}
public void toExcel(JTable table, File file){
try{
TableModel model = table.getModel();
FileWriter excel = new FileWriter(file);
for(int i = 0; i < model.getColumnCount(); i++){
excel.write(model.getColumnName(i) + "\t");
}
excel.write("\n");
for(int i=0; i< model.getRowCount(); i++) {
for(int j=0; j < model.getColumnCount(); j++) {
excel.write(model.getValueAt(i,j).toString()+"\t");
}
excel.write("\n");
}
excel.close();
}catch(IOException e){ System.out.println(e); }
}
public static void main(String[] o) {
excel cv = new excel();
cv.toExcel(cv.table,new File("C:\\Users\\itpr13266\\Desktop\\cs.tbv"));
}
}

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