I'm running a web application with Java and using Tomcat 8.5 to run it locally. My application has to read an Excel file and save the data in variables. I use the POI library, and when I execute the code without going through the server from the main method, it reads it perfectly, but when I do it through a servlet throw an exception.
This is the code that works:
package excel;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.text.ParseException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.usermodel.WorkbookFactory;
import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
public class LeerXLSX {
/*public LeerXLSX(){
}*/
public LeerXLSX(File fileName) throws ParseException{
if (fileName.exists()) {
System.out.println("Existe");
}
ArrayList cellDataList = new ArrayList();
try{
FileInputStream fileInputStream = new FileInputStream(fileName);
XSSFWorkbook workBook = new XSSFWorkbook(fileInputStream);
XSSFSheet hssfSheet = workBook.getSheetAt(0);
Iterator rowIterator = hssfSheet.rowIterator();
while (rowIterator.hasNext()){
XSSFRow hssfRow = (XSSFRow) rowIterator.next();
Iterator iterator = hssfRow.cellIterator();
ArrayList cellTempList = new ArrayList();
while (iterator.hasNext()){
XSSFCell hssfCell = (XSSFCell) iterator.next();
cellTempList.add(hssfCell);
}
cellDataList.add(cellTempList);
}
}catch (Exception e){
e.printStackTrace();
}
Leer(cellDataList);
}
private void Leer(ArrayList cellDataList) {
int nFilas = cellDataList.size();
ArrayList<String> fila[] = new ArrayList[nFilas];
for (int i = 0; i < cellDataList.size(); i++) {
ArrayList cellTempList = (ArrayList) cellDataList.get(i);
fila[i]= new ArrayList();
for (int j = 0; j < cellTempList.size(); j++) {
XSSFCell hssfCell = (XSSFCell) cellTempList.get(j);
String stringCellValue = hssfCell.toString();
//System.out.print(stringCellValue + " ");
fila[i].add(stringCellValue);
}
System.out.println("fila" + i +fila[i]);
}
}
public static void main(String[] args) throws ParseException {
File f = new File("test.xlsx");
if (f.exists()) {
LeerXLSX pb = new LeerXLSX(f);
}
}
}
When I run it through Tomcat I simply remove the main and call it from the servlet .
package excel;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.text.ParseException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.usermodel.WorkbookFactory;
import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
public class LeerXLSX {
/*public LeerXLSX(){
}*/
public LeerXLSX(File fileName) throws ParseException{
if (fileName.exists()) {
System.out.println("Existe");
}
ArrayList cellDataList = new ArrayList();
try{
FileInputStream fileInputStream = new FileInputStream(fileName);
XSSFWorkbook workBook = new XSSFWorkbook(fileInputStream);
XSSFSheet hssfSheet = workBook.getSheetAt(0);
Iterator rowIterator = hssfSheet.rowIterator();
while (rowIterator.hasNext()){
XSSFRow hssfRow = (XSSFRow) rowIterator.next();
Iterator iterator = hssfRow.cellIterator();
ArrayList cellTempList = new ArrayList();
while (iterator.hasNext()){
XSSFCell hssfCell = (XSSFCell) iterator.next();
cellTempList.add(hssfCell);
}
cellDataList.add(cellTempList);
}
}catch (Exception e){
e.printStackTrace();
}
Leer(cellDataList);
}
private void Leer(ArrayList cellDataList) {
int nFilas = cellDataList.size();
ArrayList<String> fila[] = new ArrayList[nFilas];
for (int i = 0; i < cellDataList.size(); i++) {
ArrayList cellTempList = (ArrayList) cellDataList.get(i);
fila[i]= new ArrayList();
for (int j = 0; j < cellTempList.size(); j++) {
XSSFCell hssfCell = (XSSFCell) cellTempList.get(j);
String stringCellValue = hssfCell.toString();
//System.out.print(stringCellValue + " ");
fila[i].add(stringCellValue);
}
System.out.println("fila" + i +fila[i]);
}
}
/*public static void main(String[] args) throws ParseException {
File f = new File("test.xlsx");
if (f.exists()) {
LeerXLSX pb = new LeerXLSX(f);
}
}*/
}
... and the servlet :
package controlador;
import java.io.File;
import java.io.IOException;
import java.text.ParseException;
import java.util.ArrayList;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
/**
* Servlet implementation class ServletExcel
*/
@WebServlet("/ServletExcel")
public class ServletExcel extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public ServletExcel() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
File f = new File("C:/Users/CrisH/workspace/Proyectos/test.xlsx");
try {
LeerXLSX l = new LeerXLSX(f);
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
}
}
The error it sends me is:
GRAVE: El Servlet.service() para el servlet [controlador.ServletExcel] en el contexto con ruta [/Proyectos] lanzó la excepción [La ejecución del Servlet lanzó una excepción] con causa raíz
java.lang.ClassNotFoundException: org.apache.poi.xssf.usermodel.XSSFWorkbook
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1285)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1119)
at excel.LeerXLSX.<init>(LeerXLSX.java:35)
at controlador.ServletExcel.doGet(ServletExcel.java:43)
Debuying in XSSFWorkbook workBook = new XSSFWorkbook(fileInputStream); I skip class ApplicationFilterChain.class :
Class File Editor
Source not found
The source attachment does not contain the source for the fileApplicationFilterChain.class.
You can change the source attachment by clicking Change Attached Source below:
Previously I skipped the library cataliana.jar , downloaded it and put it back into the project.