Applet - FacesServlet communication

I've created and applet that is used to interface with a client's filesystem and comm/serial ports. I would like the applet to be able to send and retrieve data from the server/database. The applet is embedded within a JSF. I'm not sure the correct way to accomplish this. Is there anway to do this within a backing bean? Should I create a phaseListener to handle the intermediary communication between the applet and the database? A servlet filter? Any help or examples would be greatly appreciated.
Thanks,
Eric

Eric,
there is a blog entry: http://www.thoughtsabout.net/blog/archives/000033.html that explains how to access the JSF servlet from a servlet filter, which would give you an option to use this as well. However, I would use this approach only if the Applet needs to be integrated into teh JSF lifecyce - e.g. for event notification. in term of re-usability of the solution Web Services appear the best way to me.
So if you need to e.g. scan a barcode and then update a JSF form with the information and submit it then the blog entry mentioned is the better solution. Otherwise the Webservice does it as well
Frank

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         at com.shinewave.lms.core.client.ServletProxy.doInitialize(ServletProxy.java:77)
         at com.shinewave.lms.core.client.APIAdapterApplet.LMSInitialize(APIAdapterApplet.java:60)
    java.lang.NullPointerException
         at com.shinewave.lms.core.client.ServletProxy.doInitialize(ServletProxy.java:82)
         at com.shinewave.lms.core.client.APIAdapterApplet.LMSInitialize(APIAdapterApplet.java:60)
    Please help me to solve this problem, thank you very much.

    Hi..
    Sorry abt this. But I was hoping if u could help out on this..
    I am trying to implement a applet to servlet communication...
    wherin the servlet would read data from the database... and send it back to the applet which gets displayed on the applet...
    But the problem is that the applet is not able to establish a connection with the servlet..
    I am also using another supportive class whose object is basically passed from the servlet to the applet..
    could u help me..
    below is the piece of code...
    APPLET:
    import java.net.*;
    import java.awt.*;
    import javax.swing.*;
    import java.awt.event.*;
    import java.io.*;
    import java.util.*;
    public class TestApplet extends JApplet implements ActionListener
         JButton btnLoad;
         JTextField tfEmpno, tfFname, tfLname, tfSalary;
         URL url;
    private String webServerStr = null;
    private String hostName = "sandy";
    private int port = 8085;
    private String servletPath = "/jdbcTest.DBDetailsServlet";     
    public TestApplet()
         super();
    // suppress Warning Message
    getRootPane().putClientProperty"defeatSystemEventQueueCheck",Boolean.TRUE);
         public void actionPerformed(ActionEvent ae)
              if(btnLoad.getText().equals("Load"))
                   if(loadData())
                        btnLoad.setText("Save");
              else
                   btnLoad.setText("Load");
    //               saveData();
         public void init()
              setBackground(Color.pink);
              tfEmpno = new JTextField(10);
              tfFname = new JTextField(10);
              tfLname = new JTextField(10);
              tfSalary= new JTextField(10);
              JPanel panel = new JPanel();
              panel.setLayout(new FlowLayout());
              panel.add(tfEmpno);
              panel.add(tfFname);
              panel.add(tfLname);
              panel.add(tfSalary);
              getContentPane().add(panel, BorderLayout.CENTER);
              JPanel bottom = new JPanel(new FlowLayout());
              btnLoad = new JButton("Load");
              btnLoad.addActionListener(this);
              bottom.add(btnLoad);
              getContentPane().add(bottom, BorderLayout.SOUTH);
         public boolean loadData()
              try
         System.out.println("Web Server host name: " + hostName);
         webServerStr = "http://" + hostName + ":" + port + servletPath;
         System.out.println("Web String full = " + webServerStr);
                   String servletGET = webServerStr + "?"
         + URLEncoder.encode("UserOption") + "="
         + URLEncoder.encode("AppletDisplay");     
    //               url = new URL(getCodeBase(),"http://sandy:8080/servlet/jdbcTest.DBDetailsServlet");
                   System.out.println("Complete Servlet Url => " + servletGET);
                   url = new URL(servletGET);
                   URLConnection con = url.openConnection();
                   con.setUseCaches(false); // Turn off caching.
                   InputStream in = con.getInputStream();
                   System.out.println("\nsuccess ....... con.getInputStream() ");
                   ObjectInputStream ois = new ObjectInputStream(in);
                   System.out.println("\nsuccess ....... new ObjectInputStream(in) ");
                   Object object = ois.readObject();
                   System.out.println("\nGot the object from servlet...");
                   if(object != null)
                        System.out.println("\nObject NOT null ...");
                        ArrayList result = (ArrayList) object;
                        jdbcTest.EmployeeValue empval = (jdbcTest.EmployeeValue) result.get(0);
                        tfEmpno.setText(""+empval.getEmp_no());
                        tfFname.setText(empval.getFname());
                        tfLname.setText(empval.getLname());
                        tfSalary.setText(""+empval.getSalary());
                        System.out.println("\nObject processed " + result);
                        repaint();
                   return true;
              catch(Exception e)
                   e.printStackTrace();
                   System.out.println("\n\n loadData()=> E X C E P T I O N : " + e + "\n");
                   return false;               
         public void saveData()
              //yet to be implemented..
    SERVLEt:
    package jdbcTest;
    import java.util.*;
    import java.io.*;
    import javax.servlet.*;
    import javax.servlet.http.*;
    public class DBDetailsServlet extends HttpServlet
         public void doGet(HttpServletRequest req,HttpServletResponse res )throws ServletException, IOException
              System.out.println("\nInside the doGet()\n");
              ArrayList results = getDetails();
              ObjectOutputStream oos = new ObjectOutputStream(res.getOutputStream());
              oos.writeObject(results);
         public void doPost(HttpServletRequest req,HttpServletResponse res )throws ServletException, IOException
              System.out.println("\nInside the doPost()\n");
              doGet(req,res);
         public ArrayList getDetails()
              try
                   System.out.println("\nServlet : inside GetDetails...");
                   Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
                   java.sql.Connection con = java.sql.DriverManager.getConnection("jdbc:odbc:SandyDSN","","");
                   java.sql.Statement stmt = con.createStatement();
                   System.out.println("\n Statement created..");
                   java.sql.ResultSet rs = stmt.executeQuery("SELECT * FROM EMP WHERE EMP_NO = 222");
                   System.out.println("\n Query Executed...");
                   ArrayList results = new ArrayList();
                   while(rs.next())
                        EmployeeValue empval = new EmployeeValue();
                        empval.setEmp_no(rs.getLong("EMP_NO"));
                        empval.setFname(rs.getString("FNAME"));
                        empval.setLname(rs.getString("LNAME"));
                        empval.setSalary(rs.getLong("SALARY"));
                        results.add(empval);
                   System.out.println("\n Resultset Obtained...");
                   stmt.close();
                   con.close();
                   return results;
              catch(Exception e)
                   System.out.println("Error while retreiving details....." + e);
                   return null;
         public boolean saveDetails(EmployeeValue empval)
              try
                   return true;
              catch(Exception e)
                   System.out.println("Error while updating details....." + e);
                   return false;
    The utility class EMployeeValue is as below:
    package jdbcTest;
    import java.io.*;
    class EmployeeValue implements Serializable
         private long emp_no;
         private String fname;
         private String lname;
         private long salary;
         public EmployeeValue()
              super();
         public EmployeeValue(long eno, String fn, String ln,long sal)
              super();
              setEmp_no(eno);
              setFname(fn);
              setLname(ln);
              setSalary(sal);
         public long getEmp_no()
              return emp_no;
         public java.lang.String getFname()
              return fname;
         public java.lang.String getLname()
              return lname;
         public long getSalary()
              return salary;
         public void setEmp_no(long newEmp_no)
              emp_no = newEmp_no;
         public void setFname(java.lang.String newFname)
              fname = newFname;
         public void setLname(java.lang.String newLname)
              lname = newLname;
         public void setSalary(long newSalary)
              salary = newSalary;

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