Gerando numeros automaticamente em Java (Sequencial)

import java.awt.*;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.sql.Connection;

import java.sql.SQLException;

import java.sql.Statement;

JLabel PacCodigo, PacNome, PacRG, PacCPF, PacTelefone, PacCelular, PacEmail, PacSexo,PacSenha, obs;
JTextField JPacCodigo, JPacNome, JPacRG, JPacCPF, JPacTelefone, JPacCelular, JPacEmail; 
JPasswordField PPacSenha;
JComboBox BSexo;
JButton BPacSalvar, BPacNovo, BPacCancelar, BPacExcluir;
ImageIcon canc=new ImageIcon("canc.jpg");




Connection conexao = Conectar.getConnection() ;
String status = Conectar.status ;

public FunCadastro (){
	
	super("Cadastrar Funcionario",new Dimension(500,360));
	
PacCodigo=new JLabel ("Codigo");
PacCodigo.setBounds(20,20,50,15);

JPacCodigo= new JTextField(""); // Caixa do codigo
JPacCodigo.setBounds(70,15,40,25);

PacNome = new JLabel("Nome");
PacNome.setBounds(120,20,50,15);

JPacNome= new JTextField("");
JPacNome.setBounds(170,15,300,25);

PacCPF= new JLabel("CPF");
PacCPF.setBounds(20,60,50,15);

JPacCPF= new JTextField("");
JPacCPF.setBounds(70,55,170,25);

PacRG= new JLabel("RG");
PacRG.setBounds(265,60,25,15);

JPacRG= new JTextField("");
JPacRG.setBounds(295,55,175,25);

PacTelefone= new JLabel("Telefone");
PacTelefone.setBounds(20,100,50,15);

JPacTelefone= new JTextField("");
JPacTelefone.setBounds(70,95,160,25);

PacCelular= new JLabel("Celular");
PacCelular.setBounds(255,100,45,15);

JPacCelular= new JTextField("");
JPacCelular.setBounds(305,95,165,25);

PacEmail= new JLabel("E-mail");
PacEmail.setBounds(20,145,50,15);

JPacEmail= new JTextField("");
JPacEmail.setBounds(70,140,400,25);

PacSexo= new JLabel("Sexo");
PacSexo.setBounds(20,190,50,15);

String Sexo[]={"Feminino", "Masculino"}; 
BSexo=new JComboBox(Sexo);
BSexo.setBounds(70,185,100,30);

PacSenha=new JLabel("Senha");
PacSenha.setBounds(200,190,50,15);

PPacSenha=new JPasswordField("");
PPacSenha.setBounds(260,185,210,25);

BPacSalvar= new JButton(new ImageIcon("src/salv.png"));
BPacSalvar.setText("Salvar");
BPacSalvar.setBounds(30,240,200,35);

BPacNovo= new JButton(new ImageIcon("src/limp.png"));
BPacNovo.setText("Limpar");
BPacNovo.setBounds(250,240,200,35);

BPacCancelar= new JButton(new ImageIcon("src/voltar.png"));
BPacCancelar.setText("Voltar");
BPacCancelar.setBounds(30,280,200,35);

BPacExcluir= new JButton(new ImageIcon("src/canc.png"));
BPacExcluir.setText("Excluir");
BPacExcluir.setBounds(250,280,200,35);


getContentPane().add(PacCodigo);
getContentPane().add(JPacCodigo);
getContentPane().add(PacNome);
getContentPane().add(JPacNome);
getContentPane().add(PacCPF);
getContentPane().add(JPacCPF);
getContentPane().add(PacRG);
getContentPane().add(JPacRG);
getContentPane().add(PacTelefone);
getContentPane().add(JPacTelefone);
getContentPane().add(PacCelular);
getContentPane().add(JPacCelular);
getContentPane().add(PacEmail);
getContentPane().add(JPacEmail);
getContentPane().add(PacSexo);
getContentPane().add(BSexo);
getContentPane().add(PacSenha);
getContentPane().add(PPacSenha);
getContentPane().add(BPacSalvar);
getContentPane().add(BPacNovo);
getContentPane().add(BPacCancelar);
getContentPane().add(BPacExcluir);



BPacNovo.addActionListener(this);
BPacCancelar.addActionListener(this);

public void Limpar(){
	JPacCodigo.setText(null);
	JPacNome.setText(null);
	JPacCPF.setText(null);
	JPacRG.setText(null);
	JPacTelefone.setText(null);
	JPacCelular.setText(null);
	JPacEmail.setText(null);
	PPacSenha.setText(null);

}


	
	public void actionPerformed1(ActionEvent acao){
		
	if (acao.getSource()==BPacNovo){
			Limpar();
					}
		else if (acao.getSource()==BPacCancelar){
			dispose();
		}
}