POI读取Excel 03/07

Java Application可以成功读取excel 03及excel 07，但是在JSP servlet中却莫名其妙不能读取excel 07(.xlsx)中的内容，只能读取excel 03(.xls)中的内容。问题没有解决。
 
/**
 * 需要如下jar包.
 * poi-3.7-20101029.jar, poi-ooxml-3.7-20101029.jar,
 * xmlbeans-2.3.0.jar, poi-ooxml-schemas-3.7-20101029.jar, dom4j-1.6.1.jar
 */
 
import java.io.*;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.ss.usermodel.*;
 
public class POIExcelUtils {  
    public POIExcelUtils() {
    }
    /**
     * 读取excel，支持excel 97~03 / excel 07
     * @param fileName : 文件名
     */
    public void read(String fileName) {
       Workbook wb = null;
       File f = new File(fileName);
       FileInputStream is;
       try {
           is = new FileInputStream(f);
           wb = WorkbookFactory.create(is);
           readWB(wb);
           is.close();
       } catch (FileNotFoundException e) {
           System.out.println(e.getMessage());
       } catch (IOException e) {
           System.out.println(e.getMessage());
       } catch (InvalidFormatException e) {
           System.out.println(e.getMessage());
       }    
    }
    /**
     * 读取excel，支持excel 97~03 / excel 07
     * @param is : 文件流
     */
    public void read(InputStream is) {
       Workbook wb;
       try {
           wb = WorkbookFactory.create(is);
           readWB(wb);
           is.close();
       } catch (InvalidFormatException e) {
           System.out.println(e.getMessage());
       } catch (IOException e) {
           System.out.println(e.getMessage());
       }
     
    }
    /** 
     * 读取Workbook 
     * @param wb 
     * @throws Exception 
     */ 
    private void readWB(Workbook wb){  
        try {  
        // 读取sheet0
            //for (int k = 0; k < wb.getNumberOfSheets(); k++) {     
                //sheet  
                //Sheet sheet = wb.getSheetAt(k); 
             Sheet sheet = wb.getSheetAt(0);
             readRows(sheet); // 按行读取
             //-- test
             /*
             System.out.println("PhysicalNumberOfRows:"+sheet.getPhysicalNumberOfRows());
             System.out.println("FirstRowNum:"+sheet.getFirstRowNum());
             System.out.println("LastRowNum:"+sheet.getLastRowNum());
             */          
            //}  
        } catch (Exception e) {     
            System.out.println(e.getMessage());  
        }  
    }
    /**
     * 读取每一行
     * @param rows : 有效行数 /非空行数
     */
    private void readRows(Sheet sheet) {
        int rows = sheet.getPhysicalNumberOfRows();
        System.out.println(rows);
        int rowIndex = 0; //每行索引
        int notnullRowIndex = 0; //非空行索引
        while (notnullRowIndex < rows) {
           Row row = sheet.getRow(rowIndex);
           rowIndex++;
           if (row != null) {
              readCells(row);
              notnullRowIndex++;
           }
        }
    }  
    /**
     * 读取每一行的单元格
     * @param row : 所在行数据
     */
    private void readCells(Row row) {
    int cells  = row.getPhysicalNumberOfCells();
       int cellIndex = 0; //单元格索引
       int notnullCellIndex = 0; //非空单元格索引
       while(notnullCellIndex < cells) {
           Cell cell = row.getCell(cellIndex);
           cellIndex++;
           if (cell != null) {
              String value = null;    
              switch (cell.getCellType()) {                       &n

补充：Web开发 , Jsp ,