EJB3 using FTPClient throws errors on instantiation

Question

This doesn't make sense. I have downloaded EnterpriseDT Pro for evaluation as a possible library to use within an app. I have a simple POJO command line app that runs this fine:

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Working POJO Imports
---------------------------------------------

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.FileOutputStream;
import java.io.OutputStream;
import java.io.File;

import com.enterprisedt.net.ftp.FTPClient;
import com.enterprisedt.util.debug.Level;
import com.enterprisedt.util.debug.Logger;

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Working POJO Code Snippet
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 // set up logger so that we get some output
        Logger log = Logger.getLogger(HelloClientPOJO.class);
        Logger.setLevel(Level.INFO);
        
      try {
         log.info("Creating FTP client");
         FTPClient  _ftpClient =  new FTPClient();
         
         String hostname = "123.123.123.123";
         String username = "letmein";
         String password = "please!";
         String filename1 = "C://test/file1.txt";
         String new_filename1 = "file1.txt";
         String s1 = readTextFile(filename1);
         
         log.info("Setting remote host");
         _ftpClient.setRemoteHost(hostname);

         log.info("Connecting to server " + hostname);
         _ftpClient.connect();

         log.info("Logging in with username=" + username + " and password="
                    + password);
         _ftpClient.login(username, password);

         log.info("Streaming file");
         _ftpClient.put(s1.getBytes(), new_filename1);
         log.info("File streamed");

            log.info("Quitting client");
            _ftpClient.quit();
      } catch (Exception e) {
            e.printStackTrace();
        }

---------------------------------------------

It works great from the POJO app. When I run the SAME code from an EJB3 stateless session bean (remote and local interfaces) deployed to JBoss 5, I get the following warnings in the startup logs of JBoss:

10:11:09,109 INFO [ServerImpl] JBoss (Microcontainer) [5.0.1.GA (build: SVNTag=JBoss_5_0_1_GA date=200902232048)] Started in 19s:391ms
10:11:14,875 WARN [InterceptorsFactory] EJBTHREE-1246: Do not use InterceptorsFactory with a ManagedObjectAdvisor, InterceptorRegistry should be used via the bean container
10:11:14,875 WARN [InterceptorsFactory] EJBTHREE-1246: Do not use InterceptorsFactory with a ManagedObjectAdvisor, InterceptorRegistry should be used via the bean container
10:11:14,875 WARN [InterceptorRegistry] applicable interceptors is non-existent for public java.lang.String com.mycompany.serverapp.ftp.ejb3.FTPBean.doWork()
10:11:14,890 WARN [InterceptorRegistry] applicable interceptors is non-existent for public java.lang.String com.mycompany.serverapp.ftp.ejb3.FTPBean.doWork()

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And I get the following error in the console log when I try to even instantiate the FTPClient class in the EJB after calling it from the POJO client application:
Exception in thread "main" javax.ejb.EJBException: Unexpected Error
java.lang.NoClassDefFoundError: com/enterprisedt/util/debug/Logger
at com.braincannon.ipublisher.ftp.ejb3.FTPBean.doWork(FTPBean.java:18)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.jboss.aop.joinpoint.MethodInvocation.invokeTarget(MethodInvocation.java:122)
at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:111)
at org.jboss.ejb3.EJBContainerInvocationWrapper.invokeNext(EJBContainerInvocationWrapper.java:69)
at org.jboss.ejb3.interceptors.aop.InterceptorSequencer.invoke(InterceptorSequencer.java:73)
at org.jboss.ejb3.interceptors.aop.InterceptorSequencer.aroundInvoke(InterceptorSequencer.java:59)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)

---------------------------------------------
EJB Code Including Instantiating FTPClient (based on the demos):

package com.mycompany.serverapp.ftp.ejb3;

import com.enterprisedt.net.ftp.FTPClient;
import com.enterprisedt.util.debug.Level;
import com.enterprisedt.util.debug.Logger;

import java.util.Vector;
import java.io.*;
import java.text.ParseException;

import javax.ejb.Stateless;

@Stateless
public class FTPBean implements FTPBeanLocal, FTPBeanRemote {

   public String doWork() {

        Logger log = Logger.getLogger(FTPBean.class);
        Logger.setLevel(Level.INFO);
   
      try {
         String filename1 = "C://test/file1.txt";
         String filename2 = "test.txt";
         String hostname = "123.123.123.123";
         String username = "letmein";
         String password = "please!";
         
         log.info("Creating FTP client");
         FTPClient ftpClient = new FTPClient();
         /*
         ftpClient.setRemoteHost(hostname);
         ftpClient.connect();
         ftpClient.login(username,password);
         ftpClient.put(filename1, filename2);
         ftpClient.quit();
         */
      } catch (Exception e) {
            e.printStackTrace();
        }

&nbsp

Answer 1

The clue is here:

java.lang.NoClassDefFoundError: com/enterprisedt/util/debug/Logger

For some reason FTPClient is failing to find its Logger class.

With EJB, this is normally because of a problem with the CLASSPATH set up for JBoss.

Are you sure that the jar file is accessible from the JBoss CLASSPATH?

Also, make sure that there are not any clashing jar files that might contain the Logger class (it's in edtftpj.jar and edtftpj-pro.jar).

Answer 2

The JAR is contained within a /lib/ folder and is referenced within the Classpath in exactly the same way as the simple POJO app I built to originally test. Again here are the imports:

import com.enterprisedt.net.ftp.FTPClient;
import com.enterprisedt.util.debug.Level;
import com.enterprisedt.util.debug.Logger;

Attached is a shot showing the build path. Again the EJB3 compiles and explodes fine when I don't make reference to the EDT FTP FTPClient or Logger classes.


[ img ][/img]

Answer 3

It is quite possible that our edtftpj.jar is also included with JBoss and that would cause a clash. Check out the full CLASSPATH, e.g. in lib/ext or anywhere that it could be found.