El código deja posicionado de esta manera al JList:
Y lo que yo deseo es esto:
Código:
String obrasSociales[] = { "Osde", "Osecac", "Galeno", "Swiss Medical"};
JList obraSocial =new JList(obrasSociales);
obraSocial.setVisibleRowCount(2);
ManejadorJList manejadorJList=new ManejadorJList();
obraSocial.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
JScrollPane scrollPane = new JScrollPane(obraSocial);
cuenta=new JTextField("",10);
nombre = new JTextField("",10);
apellido = new JTextField("",10);
dni = new JTextField("",10);
cuentaLabel = new JLabel("Cuenta");
nombreLabel = new JLabel("Nombre");
apellidoLabel = new JLabel("Apellido");
dniLabel = new JLabel("Dni");
ingresar= new JButton("Ingresar");
modificar= new JButton("Modificar");
vacio=new JLabel(" ");
GridBagLayout gbl=new GridBagLayout();
GridBagConstraints gbc=new GridBagConstraints();
FlowLayout flowLayout1=new FlowLayout();
setLayout(gbl);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.gridwidth=1;
gbc.insets=new Insets(0,0,0,0);
add(cuentaLabel, gbc);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.insets=new Insets(0,0,0,0);
gbc.gridwidth = GridBagConstraints.REMAINDER;
add(cuenta, gbc);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.gridwidth=1;
gbc.insets=new Insets(0,0,0,0);
add(nombreLabel, gbc);
gbc.gridwidth = GridBagConstraints.REMAINDER;
add(nombre, gbc);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.gridwidth=1;
gbc.insets=new Insets(0,0,0,0);
add(apellidoLabel, gbc);
gbc.gridwidth = GridBagConstraints.REMAINDER;
add(apellido, gbc);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.gridwidth=1;
gbc.insets=new Insets(0,0,0,0);
add(dniLabel, gbc);
gbc.gridwidth = GridBagConstraints.REMAINDER;
add(dni, gbc);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.gridwidth=1;
gbc.insets=new Insets(0,0,0,0);
add(ingresar, gbc);
gbc.fill=GridBagConstraints.NONE;
add(modificar,gbc);
JList obraSocial =new JList(obrasSociales);
obraSocial.setVisibleRowCount(2);
ManejadorJList manejadorJList=new ManejadorJList();
obraSocial.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
JScrollPane scrollPane = new JScrollPane(obraSocial);
cuenta=new JTextField("",10);
nombre = new JTextField("",10);
apellido = new JTextField("",10);
dni = new JTextField("",10);
cuentaLabel = new JLabel("Cuenta");
nombreLabel = new JLabel("Nombre");
apellidoLabel = new JLabel("Apellido");
dniLabel = new JLabel("Dni");
ingresar= new JButton("Ingresar");
modificar= new JButton("Modificar");
vacio=new JLabel(" ");
GridBagLayout gbl=new GridBagLayout();
GridBagConstraints gbc=new GridBagConstraints();
FlowLayout flowLayout1=new FlowLayout();
setLayout(gbl);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.gridwidth=1;
gbc.insets=new Insets(0,0,0,0);
add(cuentaLabel, gbc);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.insets=new Insets(0,0,0,0);
gbc.gridwidth = GridBagConstraints.REMAINDER;
add(cuenta, gbc);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.gridwidth=1;
gbc.insets=new Insets(0,0,0,0);
add(nombreLabel, gbc);
gbc.gridwidth = GridBagConstraints.REMAINDER;
add(nombre, gbc);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.gridwidth=1;
gbc.insets=new Insets(0,0,0,0);
add(apellidoLabel, gbc);
gbc.gridwidth = GridBagConstraints.REMAINDER;
add(apellido, gbc);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.gridwidth=1;
gbc.insets=new Insets(0,0,0,0);
add(dniLabel, gbc);
gbc.gridwidth = GridBagConstraints.REMAINDER;
add(dni, gbc);
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.anchor=GridBagConstraints.WEST;
gbc.gridwidth=1;
gbc.insets=new Insets(0,0,0,0);
add(ingresar, gbc);
gbc.fill=GridBagConstraints.NONE;
add(modificar,gbc);
Muchas gracias desde ya!!!