Java - Problema Java

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException

	at Bdd.BDDUser.rellenarTabla(BDDUser.java:67)

	at Plataforma.BandejaDeEntrada.<init>(BandejaDeEntrada.java:53)

	at Plataforma.IniciarSesion$1.actionPerformed(IniciarSesion.java:57)

	at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)

	at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)

	at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)

	at javax.swing.DefaultButtonModel.setPressed(Unknown Source)

	at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)

	at java.awt.Component.processMouseEvent(Unknown Source)

	at javax.swing.JComponent.processMouseEvent(Unknown Source)

	at java.awt.Component.processEvent(Unknown Source)

	at java.awt.Container.processEvent(Unknown Source)

	at java.awt.Component.dispatchEventImpl(Unknown Source)

	at java.awt.Container.dispatchEventImpl(Unknown Source)

	at java.awt.Component.dispatchEvent(Unknown Source)

	at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)

	at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)

	at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)

	at java.awt.Container.dispatchEventImpl(Unknown Source)

	at java.awt.Window.dispatchEventImpl(Unknown Source)

	at java.awt.Component.dispatchEvent(Unknown Source)

	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)

	at java.awt.EventQueue.access$500(Unknown Source)

	at java.awt.EventQueue$3.run(Unknown Source)

	at java.awt.EventQueue$3.run(Unknown Source)

	at java.security.AccessController.doPrivileged(Native Method)

	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)

	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)

	at java.awt.EventQueue$4.run(Unknown Source)

	at java.awt.EventQueue$4.run(Unknown Source)

	at java.security.AccessController.doPrivileged(Native Method)

	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)

	at java.awt.EventQueue.dispatchEvent(Unknown Source)

	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)

	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)

	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)

	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)

	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)

	at java.awt.EventDispatchThread.run(Unknown Source)

package Bdd;

import java.sql.*;

import javax.swing.JOptionPane;

import Plataforma.BandejaDeEntrada;

public class BDDUser {

	ConexionBDD cn;

	Plataforma.BandejaDeEntrada bandeja=null;

	public int size;

	public ResultSetMetaData rm;

	public BDDUser() {

		cn = new ConexionBDD();

	}

	public void rellenarTabla(){

		try{

			PreparedStatement pstm = cn.getConnection().prepareStatement("SELECT * from mensajes");

				ResultSet res = pstm.executeQuery();

				while(res.next()){

					Object[] fila=new Object[3];

					fila[0]=res.getString("emisor");

					fila[1]=res.getString("asunto");

					fila[2]=res.getString("mensaje");

					bandeja.getModelo().addRow(fila);

				}

				bandeja.getTable().updateUI();

				res.close();

		}catch(SQLException e){

			e.printStackTrace();

		}

	}

}

package Plataforma;

import java.awt.event.*;

import javax.swing.*;

import javax.swing.table.DefaultTableModel;

import Bdd.BDDUser;

import java.awt.BorderLayout;

import java.awt.ScrollPane;

public class BandejaDeEntrada extends JFrame {

	private static final long serialVersionUID = 1L;

	//IniciarSesion iniciar = new IniciarSesion();

	private JTable table;

	private DefaultTableModel modelo;

	public BandejaDeEntrada() {

		setTitle("Bandeja De Entrada");

		setSize(703, 367);

		getContentPane().setLayout(null);

		JButton btnActualizar = new JButton("Actualizar");

		btnActualizar.setBounds(595, 11, 89, 23);

		getContentPane().add(btnActualizar);

		JComboBox comboBox = new JComboBox();

		comboBox.setModel(new DefaultComboBoxModel(new String[] { "Enviados", "Recibidos" }));

		comboBox.setToolTipText("Enviados\r\nRecibidos");

		comboBox.setBounds(462, 12, 123, 20);

		getContentPane().add(comboBox);

		JButton btnRedactar = new JButton("Redactar");

		btnRedactar.setBounds(10, 11, 89, 23);

		getContentPane().add(btnRedactar);

		table = new JTable();

		table.setBounds(10, 45, 667, 273);

		getContentPane().add(table);

		modelo=new DefaultTableModel(){

			@Override

			public boolean isCellEditable(int fila,int columna){

				return false;

			}

		};

		table=new JTable(modelo);

		modelo.addColumn("De:");

		modelo.addColumn("Asunto");

		modelo.addColumn("Mensaje:");

		BDDUser user=new BDDUser();

		user.rellenarTabla();

			}

public BDDUser(BandejaDeEntrada bandeja) {

	cn = new ConexionBDD();

        this.bandeja = bandeja;

}

.

.

BDDUser user=new BDDUser(this);

user.rellenarTabla();

.

.