How do i get the index of the last column when reading a xlsx file using the Apache POI API?
There's a getLastRowNum method, but I can't find nothing related to the number of columns...
EDIT:
I'm dealing with XLSX files
I think you'll have to iterate through the rows and check HSSFRow.getLastCellNum() on each of them.
Check each Row and call Row.getLastCellNum() the max cell number is the last column number.
Row r = sheet.getRow(rowNum);
int maxCell= r.getLastCellNum();
To get to know the last column that has value of any row , First you need to get the row and then you can find the last column that has value
Syntax :
sheet.getrow(RowNumber).getLastCellNum();
RowNumber --> is the row number for which you want to know the last column that has value
Try this function:
private void maxExcelrowcol() {
int row, col, maxrow, maxcol;
//Put file name here for example filename.xls
String filename = "filename.xls";
static String TAG = "ExelLog";
//you can use 'this' in place of context if you want
Context context = getApplicationContext();
try {
// Creating Input Stream
File file = new File(context.getExternalFilesDir(null), filename);
FileInputStream myInput = new FileInputStream(file);
// Create a POIFSFileSystem object
POIFSFileSystem myFileSystem = new POIFSFileSystem(myInput);
// Create a workbook using the File System
HSSFWorkbook myWorkBook = new HSSFWorkbook(myFileSystem);
// Get the first sheet from workbook
HSSFSheet mySheet = myWorkBook.getSheetAt(0);
//Row iterator
Iterator rowIter = mySheet.rowIterator();
while (rowIter.hasNext()) {
HSSFRow myRow = (HSSFRow) rowIter.next();
//Cell iterator for iterating from cell to next cell of a row
Iterator cellIter = myRow.cellIterator();
while (cellIter.hasNext()) {
HSSFCell myCell = (HSSFCell) cellIter.next();
row = myCell.getRowIndex();
col = myCell.getColumnIndex();
if (maxrow < row) {
maxrow = row;
}
if (maxcol < col) {
maxcol = col;
}
}
}
} catch(FileNotFoundException e) {
e.printStackTrace();
} catch(IOException e) {
e.printStackTrace();
}
}
Related
I am using apache poi to write the data in excel file. When I am passing value to columns of first row (for heading), its value does not get updated but from row 2 onward I can see the data in excel file.
Below is the code I am using.
public static void writeWorkBook(Map<String, List<String>> addressMap, List<String> userList) {
System.out.println("Writing Process Started ");
XSSFWorkbook workbook = new XSSFWorkbook();
for (String user : userList) {
XSSFSheet sheet = workbook.createSheet("Data_" + user);
int rownum = 1;
Row row = sheet.createRow(rownum);
Cell cell = row.createCell(0);
cell.setCellValue("User");
cell = row.createCell(1);
cell.setCellValue("Address");
List<String> addressList = addressMap.get(user);
for (String s : addressList) {
row = sheet.createRow(rownum++);
cell = row.createCell(0);
cell.setCellValue(user);
cell = row.createCell(1);
cell.setCellValue(s);
}
}
try {
FileOutputStream out = new FileOutputStream(new File("D://practice/java/testWrite.xlsx"));
workbook.write(out);
out.close();
System.out.println("testWrite.xlsx written successfully on disk.");
workbook.close();
} catch (Exception e) {
e.printStackTrace();
}
}
The output I am getting is
First: All indexes are 0-based. So
...
int rownum = 1;
Row row = sheet.createRow(rownum);
...
creates the second row. First row would be
...
int rownum = 0;
Row row = sheet.createRow(rownum);
...
Second: In row = sheet.createRow(rownum++); at first the row is created and then rownum is incremented. So first row is created again instead of second row.
Do
...
row = sheet.createRow(++rownum);
...
instead.
Getting and setting the rows are 0-based, so if you want to have the description in the first row, you need use 0 as argument in
Row row = sheet.createRow(rownum);
I'm having a hard time visualizing a good way to perform this. As you can see by the below code, I'm going through every row and getting values for each cell. However, when actually running the query to add them to a table, it's easier if you can input a whole row at a time. There's enough columns/variability though where I don't want to make a separate value for each column in the excel document. Any ideas on how to run this more efficiently?
for (int i=1; i<rowNum; i++) {
XSSFRow row = ws.getRow(i) ;
for (int j = 0; j<colNum; j++) {
XSSFCell cell = row.getCell(j) ;
String value = cell.getStringCellValue();
data[i][j] = value ;
System.out.println("the value is " + value);
stmt.executeUpdate("INSERT INTO databasetable VALUES(" + value + ")");
}
}
You can spawn an iterator on your worksheet to have it more efficient.
Something like the below
public static Vector read(String fileName) {
Vector cellVectorHolder = new Vector();
try{
FileInputStream myInput = new FileInputStream(fileName);
XSSFWorkbook myWorkBook = new XSSFWorkbook(myInput);
XSSFSheet mySheet = myWorkBook.getSheetAt(0);
Iterator rowIter = mySheet.rowIterator();
while(rowIter.hasNext()){
XSSFRow myRow = (XSSFRow) rowIter.next();
Iterator cellIter = myRow.cellIterator();
List list = new ArrayList();
while(cellIter.hasNext()){
XSSFCell myCell = (XSSFCell) cellIter.next();
list.add(myCell);
}
cellVectorHolder.addElement(list);
}
}catch (Exception e){e.printStackTrace(); }
return cellVectorHolder;
}
I ended up using concentation and just inserted a , between each value in the for loop.
Using Apache POI, I am trying to read an excel file. The file has 1000 rows and 1 column. With this code:
XSSFSheet ws = workbook.getSheetAt(0);
Iterator< Row > rowIt = ws.iterator();
XSSFRow row;
int i = 0;
while ( rowIt.hasNext() ) {
row = (XSSFRow) rowIt.next();
Iterator< Cell > cellIt = row.cellIterator();
while ( cellIt.hasNext() ) {
Cell cell = cellIt.next();
my_array[ i ] = cell.getStringCellValue();
}
++i;
}
It seems that it reads 1001 rows and since the last row is "", my_array get invalid string. Is there any way to fix that? I expect rowIt.hasNext() is responsible for that but it doesn't work as expected.
The file has 1000 rows and 1 column : you must specify what column you are reading.
here an exemple that specify column with this excel file:
public class TestLecture {
public static void main(String[] args) throws IOException{
List<String> mys_list= new ArrayList<String>();
FileInputStream file = new FileInputStream(new File("test.xlsx"));
//Get the workbook instance for XLS file
XSSFWorkbook workbook = new XSSFWorkbook (file);
//Get first sheet from the workbook
XSSFSheet ws = workbook.getSheetAt(0);
//Get iterator to all the rows in current sheet
Iterator<Row> rowIt = ws.iterator();
while (rowIt.hasNext()) {
Row row = rowIt.next();
Iterator<Cell> cellIt = row.iterator();
while (cellIt.hasNext()) {
Cell cell = cellIt.next();
int columnIndex = cell.getColumnIndex();
switch (columnIndex) {
case 2:
mys_list.add(cell.getStringCellValue());
break;
}
}
}
System.out.println(mys_list.size());
for(String g :mys_list){
System.out.println(g);
}
}
}
I want to compare Excel files with each other just to see if they are the same or not. I can choose my Excel Files and Read them. I have 2 Excel Sheets with the same Content but one in .xls and on in .xlsx format.
I use the following Code to read my files (for xls with HSSFWorkbook and so on)
private String xlsx(File inputFile) {
String outputString = "";
// For storing data into String
StringBuffer data = new StringBuffer();
try {
// Get the workbook object for XLSX file
XSSFWorkbook wBook = new XSSFWorkbook(new FileInputStream(inputFile));
// Get first sheet from the workbook
XSSFSheet sheet = wBook.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();
data.append(cell + ";");
}
data.append("\n");
}
System.out.println(data.toString());
outputString = data.toString();
wBook.close();
} catch (Exception ioe) {
ioe.printStackTrace();
}
return outputString;
}
In my Excel I have blank cells - when i read them with xls I get DATA;;;;;DATA which is correct but When i Do the same in xlsx I get DATA;DATA
Somehow the Code skips empty cells?! How can I fix this Problem?
Thanks in Advance
After some more Google research and trying different things i found a solution to my Problem. The Iterator skips empty Cells because they have no value - they are null - however in a xls File it seems like they are not null - Whatever
My Code:
private String xlsx(File inputFile) {
String outputString = "";
System.out.println("start");
// For storing data into String
StringBuffer data = new StringBuffer();
try {
// Get the workbook object for XLSX file
XSSFWorkbook wBook = new XSSFWorkbook(new FileInputStream(inputFile));
// Get first sheet from the workbook
XSSFSheet sheet = wBook.getSheetAt(0);
// Decide which rows to process
int rowStart = 0;
int rowEnd = sheet.getLastRowNum()+1;
for (int rowNum = rowStart; rowNum < rowEnd; rowNum++) {
Row r = sheet.getRow(rowNum);
int lastColumn = r.getLastCellNum();
for (int cn = 0; cn < lastColumn; cn++) {
Cell c = r.getCell(cn);
if (c == null) {
data.append("" + ";");
} else {
data.append(c + ";");
}
}
data.append("\n");
}
System.out.println(data.toString());
outputString = data.toString();
wBook.close();
} catch (Exception ioe) {
ioe.printStackTrace();
}
System.out.println("end");
return outputString;
}
I need to filter my excel spreadsheet for the word "GHH" anywhere in the text of a cell in a specific column. I have managed to do this by I then need to have returned the whole row that this text is found in. This I can't do as there doesnt seem to be a way of using the getRowIndex method to then display the whole row.
Here is my code:
public static void main(String[] args) throws IOException {
FileInputStream fis = new FileInputStream(new File("myfile.xls"));
HSSFWorkbook workBook = new HSSFWorkbook(fis);
HSSFSheet sheet = workBook.getSheetAt(0);
Iterator < Row > rows = sheet.rowIterator();
while (rows.hasNext()) {
HSSFRow row = (HSSFRow) rows.next();
Iterator < Cell > cells = row.cellIterator();
while (cells.hasNext()) {
HSSFCell cell = (HSSFCell) cells.next();
if (cell.toString().contains("GHH")) {
String key = cell.getStringCellValue();
int RI = cell.getRowIndex();
}
}
}
workBook.close();
}
You could try to use a List<HSSFRow> to save filtered rows as bellow:
List<HSSFRow> filteredRows = new ArrayList<HSSFRow>();
Iterator<Row> rows= sheet.rowIterator();
while (rows.hasNext ()){
HSSFRow row = (HSSFRow) rows.next ();
Iterator<Cell> cells = row.cellIterator ();
while (cells.hasNext ()){
HSSFCell cell = (HSSFCell) cells.next ();
if (cell.toString().contains("GHH")) {
String key = cell.getStringCellValue();
int RI=cell.getRowIndex();
filteredRows.add(row);
break;
}
}
// then use filteredRows
You probably want to have two bits of logic, one for handling a "matched" row, one for matching. Something like:
DataFormatter formatter = new DataFormatter();
public void matchingRow(Row row) {
System.out.println("Row " + (row.getRowNum()+1) + " matched:");
for (Cell c : row) {
System.out.println(" " + formatter.formatCellValue(cell));
}
}
public void handleFile(File excel) throws Exception {
Workbook wb = WorkbookFactory.create(excel);
Sheet sheet = wb.getSheetAt(0);
for (Row row : sheet) {
boolean matched = false;
for (Cell cell : row) {
if (matched) continue;
if (formatter.formatCellValue(cell).contains("GHH")) {
matchingRow(row);
matched = true;
}
}
}
}
That will check every cell in the first sheet, and if the text of a cell in a row matches GHH will then print out the row's contents. If a row has that in twice, it'll only print it once