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] 

22 Answers

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:

1. poi-scratchpad-3.7-20101029
2. poi-3.2-FINAL-20081019
3. poi-3.7-20101029
4. poi-examples-3.7-20101029
5. poi-ooxml-3.7-20101029
6. poi-ooxml-schemas-3.7-20101029
7. xmlbeans-2.3.0
8. 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 @

For detailed info with example visit :

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")); } }