hassle with jakarta poi

[nomeaning]

hello, anybody who helps?

i have a hardship and dont know why.. it has to do with the argument FileInputStream that i send to the POIFSFileSystem constructor, but dont detect the error... it should show the 1st sheet's name

http://jakarta.apache.org/poi/hssf/index.html

code is below..

thanks!


classes>
classes>java -classpath org\poi\poi.jar;. org.base.TestPOI
Exception in thread "main" java.lang.NullPointerException
at org.apache.poi.util.IOUtils.readFully(IOUtils.java:51)
at org.apache.poi.util.IOUtils.readFully(IOUtils.java:36)
at org.apache.poi.poifs.storage.HeaderBlockReader.<init>(HeaderBlockReader.java:71)
at org.apache.poi.poifs.filesystem.POIFSFileSystem.<init>( POIFSFileSystem.java:83)
at org.base.TestPOI.main(TestPOI.java:29)

    
    package org.base;
     
    import org.apache.poi.hssf.usermodel.HSSFWorkbook;
    import org.apache.poi.poifs.filesystem.POIFSFileSystem ;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.IOException;
    import java.io.FileNotFoundException;
     
    public class TestPOI {
       
        private static HSSFWorkbook workBook;
        private static FileInputStream fileIn;
        private static File file;
       
        public static void main(String[] args) {
           
            File file = new File(".\\2005.xls");
           
            if(file.exists()) {
                if( file.isFile()) {
                    try {
                        FileInputStream fileIn  = new FileInputStream(file);
                    } catch (FileNotFoundException notFoundEx) {
                        notFoundEx.printStackTrace ();
                    }
                   
                    try {
                        POIFSFileSystem fs = new POIFSFileSystem(fileIn);
                        HSSFWorkbook workBook = new HSSFWorkbook(fs);
                        System.out.println(workBook.getSheetName(1));
                        fileIn.close();
                    } catch (IOException ioe) {
                        ioe.printStackTrace();
                    }
                } else {
                    System.out.println("Si existe pero no es archivo");
                }
            } else {
                System.out.println("No existe");
            }
        }
    }

[Ulf Dittmer]

Is the file readable in the sense that File.canRead() returns true?

[nomeaning]

yes, it can be readable... but i dont know what happens...

but instead i have written the code like this:

package org.base;
 
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.FileNotFoundException;
 
public class TestPOI {

private static HSSFWorkbook workBook;
private static FileInputStream fileIn;

public static void main(String[] args) throws FileNotFoundException, IOException {

POIFSFileSystem fs = new POIFSFileSystem(new FileInputStream(".\\2005.xls"));
HSSFWorkbook workBook = new HSSFWorkbook(fs);
System.out.println(workBook.getSheetName(1));
}

}

and it worked well... but i have still the question mark