Povoar ComboBox

Programação Java
#1

Olá galera, Bom estou tentando preencher o meu JComboBox com dados do BancoDeDados, em especifico de uma Chave primaria da tabela, estou a tentar o seguinte codigo:

    String a = "SELECT CodProcesso from processo";    
    PreparedStatement smt = conexao.prepareStatement(a);    
    ResultSet rs;    
    rs = smt.executeQuery(a);    
   while (rs.next())    
   {    
       jComboBox1.addItem(rs.getString("CodProcesso"));    
    }

Bom a principio o cidigo parece certo, Porem ele não preenche o ComboBox…
Alguem sabe o porque ?
Obs: Da aquele erro de nullPointer…

#2

Você instanciou o JComboBox :?:

:thumbup:

#3

Sim Sim! Tanto que em outra tentativa eu tentei a por os códigos dentro de um método e colocar como parâmetro o ComboBox na hora de chamar, Porem mesmo assim foi falido a tentativa :frowning:

#4

mostre seu código todo

#5

Ok

package Grafico;


import Codigos.ClasseMoagem;
import DAOClasses.ClasseRegistroDAO;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JComboBox;

/**
 *
 * @author Administrador
 */
public class JFRegistro extends javax.swing.JFrame {
    private Connection conexao;

    /**
     * Creates new form JFRegistro
     */
    public JFRegistro() throws SQLException {
        initComponents();      
        combo(jComboBox1);
    }

    
    void combo(JComboBox comb) throws SQLException{
     String query = "SELECT * FROM processo";
     PreparedStatement smt = conexao.prepareStatement(query);
    ResultSet rs;    
    rs = smt.executeQuery(query);    
   while (rs.next())    
   {    
       comb.addItem(rs.getString("CodProcesso"));    
    }
    }
    

    // Variables declaration - do not modify
    private javax.swing.JButton jButton10;
    public static javax.swing.JButton jButton11;
    private javax.swing.JButton jButton12;
    private javax.swing.JButton jButton13;
    public static javax.swing.JButton jButton14;
    private javax.swing.JButton jButton15;
    private javax.swing.JButton jButton16;
    public static javax.swing.JButton jButton17;
    private javax.swing.JButton jButton18;
    private javax.swing.JButton jButton19;
    public static javax.swing.JButton jButton20;
    private javax.swing.JButton jButton21;
    private javax.swing.JButton jButton4;
    public static javax.swing.JButton jButton5;
    private javax.swing.JButton jButton6;
    private javax.swing.JButton jButton7;
    public static javax.swing.JButton jButton8;
    private javax.swing.JButton jButton9;
    private javax.swing.JComboBox jComboBox1;
    private javax.swing.JFormattedTextField jFormattedTextField1;
    private javax.swing.JFormattedTextField jFormattedTextField10;
    private javax.swing.JFormattedTextField jFormattedTextField11;
    private javax.swing.JFormattedTextField jFormattedTextField12;
    private javax.swing.JFormattedTextField jFormattedTextField13;
    private javax.swing.JFormattedTextField jFormattedTextField14;
    private javax.swing.JFormattedTextField jFormattedTextField15;
    private javax.swing.JFormattedTextField jFormattedTextField16;
    private javax.swing.JFormattedTextField jFormattedTextField17;
    private javax.swing.JFormattedTextField jFormattedTextField18;
    private javax.swing.JFormattedTextField jFormattedTextField2;
    private javax.swing.JFormattedTextField jFormattedTextField3;
    private javax.swing.JFormattedTextField jFormattedTextField4;
    private javax.swing.JFormattedTextField jFormattedTextField5;
    private javax.swing.JFormattedTextField jFormattedTextField6;
    private javax.swing.JFormattedTextField jFormattedTextField7;
    private javax.swing.JFormattedTextField jFormattedTextField8;
    private javax.swing.JFormattedTextField jFormattedTextField9;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel10;
    private javax.swing.JLabel jLabel11;
    private javax.swing.JLabel jLabel12;
    private javax.swing.JLabel jLabel13;
    private javax.swing.JLabel jLabel14;
    private javax.swing.JLabel jLabel15;
    private javax.swing.JLabel jLabel16;
    private javax.swing.JLabel jLabel17;
    private javax.swing.JLabel jLabel18;
    private javax.swing.JLabel jLabel19;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JLabel jLabel20;
    private javax.swing.JLabel jLabel21;
    private javax.swing.JLabel jLabel22;
    private javax.swing.JLabel jLabel23;
    private javax.swing.JLabel jLabel24;
    private javax.swing.JLabel jLabel25;
    private javax.swing.JLabel jLabel26;
    private javax.swing.JLabel jLabel27;
    private javax.swing.JLabel jLabel28;
    private javax.swing.JLabel jLabel29;
    private javax.swing.JLabel jLabel3;
    private javax.swing.JLabel jLabel30;
    private javax.swing.JLabel jLabel31;
    private javax.swing.JLabel jLabel32;
    private javax.swing.JLabel jLabel33;
    private javax.swing.JLabel jLabel34;
    private javax.swing.JLabel jLabel35;
    private javax.swing.JLabel jLabel36;
    private javax.swing.JLabel jLabel37;
    private javax.swing.JLabel jLabel38;
    private javax.swing.JLabel jLabel39;
    private javax.swing.JLabel jLabel4;
    private javax.swing.JLabel jLabel40;
    private javax.swing.JLabel jLabel41;
    private javax.swing.JLabel jLabel42;
    private javax.swing.JLabel jLabel43;
    private javax.swing.JLabel jLabel44;
    private javax.swing.JLabel jLabel45;
    private javax.swing.JLabel jLabel46;
    private javax.swing.JLabel jLabel47;
    private javax.swing.JLabel jLabel48;
    private javax.swing.JLabel jLabel49;
    private javax.swing.JLabel jLabel5;
    private javax.swing.JLabel jLabel50;
    private javax.swing.JLabel jLabel51;
    private javax.swing.JLabel jLabel52;
    private javax.swing.JLabel jLabel53;
    private javax.swing.JLabel jLabel6;
    private javax.swing.JLabel jLabel7;
    private javax.swing.JLabel jLabel8;
    private javax.swing.JLabel jLabel9;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JPanel jPanel10;
    private javax.swing.JPanel jPanel11;
    private javax.swing.JPanel jPanel12;
    private javax.swing.JPanel jPanel13;
    private javax.swing.JPanel jPanel14;
    private javax.swing.JPanel jPanel15;
    private javax.swing.JPanel jPanel2;
    private javax.swing.JPanel jPanel3;
    private javax.swing.JPanel jPanel4;
    private javax.swing.JPanel jPanel5;
    private javax.swing.JPanel jPanel6;
    private javax.swing.JPanel jPanel7;
    private javax.swing.JPanel jPanel8;
    private javax.swing.JTabbedPane jTabbedPane1;
    private javax.swing.JTextField jTextField2;
    private javax.swing.JTextField jTextField3;
    private javax.swing.JTextField jTextField4;
    private javax.swing.JTextField jTextField5;
    private javax.swing.JTextField jTextField6;
    private javax.swing.JTextField jTextField7;
    private javax.swing.JTextField jTextField8;
    private javax.swing.JTextField jTextField9;
    // End of variables declaration
}

So lembrando, Ja tentei colocar em metodos, e chamar no construtor e em eventos de Windows…

#6