Help in jxls reader - apache-poi

Question

HI
I am new to jxls. I read the articles regarding it, but seems not so good examples there. I am reading a xls file through java.
Please find the simple attached xls file for the same.
1)
public class Employee {
private String rollno;
private String name;
private String percentage;
2)
<worksheet name="Sheet1">
<section endRow="1" startRow="0"/>
<loop endRow="4" items="employee" startRow="3" var="emp" varType="com.Employee">
<section endRow="4" startRow="3">
<mapping col="0" row="3">emp.rollno</mapping>
<mapping col="1" row="3">emp.name</mapping>
<mapping col="2" row="3">emp.percentage</mapping>
</section>
</loop>
</worksheet>
3)
public class Client {
public static void main(String[] args) throws IOException, SAXException {
InputStream inputXML = new BufferedInputStream(new FileInputStream("C:\\NewFile1.xml"));
XLSReader mainReader = ReaderBuilder.buildFromXML( inputXML );
InputStream inputXLS = new BufferedInputStream(new FileInputStream("c:\\Book1.xls"));
Employee employee = new Employee();
System.out.println("Is Null inputXML:"+inputXML==null);
System.out.println("Is Null inputXLS:"+inputXLS==null);
Map beans = new HashMap();
beans.put("employee", employee);
XLSReadStatus readStatus = mainReader.read( inputXLS, beans);
readStatus.toString();
}
}
I am getting a exception as
Feb 21, 2011 3:59:17 PM net.sf.jxls.reader.XLSReaderImpl readSheet
INFO: Processing sheet Sheet1
Exception in thread "main" java.lang.NullPointerException
at net.sf.jxls.reader.XLSForEachBlockReaderImpl.read(XLSForEachBlockReaderImpl.java:45)
at net.sf.jxls.reader.XLSSheetReaderImpl.read(XLSSheetReaderImpl.java:25)
at net.sf.jxls.reader.XLSReaderImpl.readSheet(XLSReaderImpl.java:45)
at net.sf.jxls.reader.XLSReaderImpl.read(XLSReaderImpl.java:31)
at com.GetTheData.main(GetTheData.java:41)
Please help in solving this prob.
Thank you

Answer 1

You need to define a loopbreakcondition to stop the loop iteration based on some condition.
For example:
<worksheet name="Sheet1">
<section endRow="1" startRow="0"/>
<loop endRow="4" items="employee" startRow="3" var="emp" varType="com.Employee">
<section endRow="4" startRow="3">
<mapping col="0" row="3">emp.rollno</mapping>
<mapping col="1" row="3">emp.name</mapping>
<mapping col="2" row="3">emp.percentage</mapping>
</section>
<loopbreakcondition>
<rowcheck offset="0">
<cellcheck offset="0">END</cellcheck>
</rowcheck>
</loopbreakcondition>
</loop>
</worksheet>
Take a look at the user guide for more information.

Answer 2

Client.java this line : beans.put("employee", employee);
change to :
beans.put("employee", new ArrayList() );
works for me.