private void listar_Impresoras (){
    String [] separada; 
    separada = jComboBox1.getSelectedItem().toString().split("-"); 
    int modulo = Integer.parseInt(separada[0].trim());
    r_con.Connection();
    Vector<Vector<String>>v = r_con.getContenidoTabla("SELECT * FROM impresoras WHERE imp_id_modulo = "+modulo);
    DefaultListModel modelo = new DefaultListModel();
    for(Vector<String>a:v){
        modelo.addElement(a.elementAt(0));
        //jComboBox1.addItem(a.elementAt(0)+" - "+a.elementAt(1));
    }
    v=null;
    r_con.cierraConexion();
    jList1.setModel(modelo);
jList1.setSelectionModel(new DefaultListSelectionModel() {
    private int i0 = -1;
    private int i1 = -1;

    public void setSelectionInterval(int index0, int index1) {
        if(i0 == index0 && i1 == index1){
            if(getValueIsAdjusting()){
                 setValueIsAdjusting(false);
                 setSelection(index0, index1);
            }
        }else{
            i0 = index0;
            i1 = index1;
            setValueIsAdjusting(false);
            setSelection(index0, index1);
        }
    }
    private void setSelection(int index0, int index1){
        if(super.isSelectedIndex(index0)) {
            super.removeSelectionInterval(index0, index1);
        }else {
            super.addSelectionInterval(index0, index1);
        }
    }
});
}