There is a use case where in you need to import data from a CSV file into a View Object, Here i will explain a use case where in i will be importing the attendance for a particular student.
The CSV file will be in a format as below(first line will be header info and subsequent lines will have attendance data)
SSN,Name,MonHrs,TueHrs,WedHrs,ThuHrs,FriHrs,SatHrs,SunHrs
1234-12-123,Sanjeeb,8,8,8,8,8,8,8
4567-56-987,XYZ,7,8,5,8,8,7,8
In my page i have dropped a upload component i.e.
<af:inputFile/> which will allow me to select a file from my system and import the data into View object. To achieve the same i have implemented a
valueChangeListener method in a managed bean for this component . The code below are self explanatory as i have included comments to understand better.
public void
fileUploaded(ValueChangeEvent valueChangeEvent) {
//getting the file instance from the event.
UploadedFile file = (UploadedFile)valueChangeEvent.getNewValue();
try {
//calling a private method to parse the CSV file and import the data into table component
parseFile(file.getInputStream());
//Refresh the table component programmatically,
importTab is the binding of the table component
AdfFacesContext.getCurrentInstance().addPartialTarget(
importTab);
} catch (IOException e) {
// TODO : Handle your exception
}
}
private void
parseFile(java.io.InputStream file) {
BufferedReader reader =
new BufferedReader(new InputStreamReader(file));
String strLine = "";
StringTokenizer st = null;
int lineNumber = 0, tokenNumber = 0;
Row rw = null;
CollectionModel _tableModel = (CollectionModel)impTab.getValue();
//the ADF object that implements the CollectionModel is JUCtrlHierBinding. It
//is wrapped by the CollectionModel API
JUCtrlHierBinding _adfTableBinding =
(JUCtrlHierBinding)_tableModel.getWrappedData();
//Acess the ADF iterator binding that is used with ADF table binding
DCIteratorBinding it = _adfTableBinding.getDCIteratorBinding();
//read comma separated file line by line
try {
while ((strLine = reader.readLine()) != null) {
lineNumber++;
// create a new row skip the header (header has linenumber 1)
if (lineNumber > 1) {
rw = it.getNavigatableRowIterator().createRow();
rw.setNewRowState(Row.STATUS_INITIALIZED);
it.getNavigatableRowIterator().insertRow(rw);
}
//break comma separated line using ","
st = new StringTokenizer(strLine, ",");
while (st.hasMoreTokens()) {
//display csv values
tokenNumber++;
String theToken = st.nextToken();
System.out.println("Line # " + lineNumber + ", Token # " +
tokenNumber + ", Token : " + theToken);
if (lineNumber > 1) {
// set Attribute Values
switch (tokenNumber) {
case 1:
rw.setAttribute("Ssn", theToken);
case 2:
rw.setAttribute("Firstname", theToken);
case 3:
rw.setAttribute("Monhrs", theToken);
case 4:
rw.setAttribute("Tuehrs", theToken);
case 5:
rw.setAttribute("Wedhrs", theToken);
case 6:
rw.setAttribute("Thrhrs", theToken);
case 7:
rw.setAttribute("Frihrs", theToken);
case 8:
rw.setAttribute("Sathrs", theToken);
case 9:
rw.setAttribute("Sunhrs", theToken);
}
}
}
//reset token number
tokenNumber = 0;
}
} catch (IOException e) {
// TODO add more
FacesContext fctx = FacesContext.getCurrentInstance();
fctx.addMessage(impTab.getClientId(fctx),
new FacesMessage(FacesMessage.SEVERITY_ERROR,
"Content Error in Uploaded file",
e.getMessage()));
} catch (Exception e) {
FacesContext fctx = FacesContext.getCurrentInstance();
fctx.addMessage(null,
new FacesMessage(FacesMessage.SEVERITY_ERROR, "Data Error in Uploaded file",
e.getMessage()));
}
}
Hope it helps !!!
