java - 如何将数据库中的列值获取到 jLabels

Question

在我的数据库表中，有一列包含不同的数据。我想要的是检索该列中的所有数据并将它们放在 JLabel 上。即在我的数据库中。

name
Aaron
Baldwin
Gabriel
Harold

现在我有 1 个空 jLabel，但是如何从数据库中检索值并在插入新数据时将每个值放入标签中？插入新数据时，需要创建包含该数据的新 jLabel。

我尝试过的。

private void getNames() {

    String sql = "SELECT * FROM details";
    try
    {
        con = Db.getConnection();
        pst = con.prepareStatement(sql);
        rs = pst.executeQuery();

        while(rs.next())
        {
           jLabel1.setText(rs.getString("name"));
        }
    }
}

Answer 1

如果您使用表格，下面的代码将:

public class Test extends JPanel{

    private static final long serialVersionUID = 1L;

    List<Object> objects = new ArrayList<Object>();

    JTable billTable = new JTable();
    JTableBinding<UiBillItem, UiBill, JTable> jTableBinding;

    private void init(){
        objects = getNames();
    }

    private List<Object> getNames() {
        // for better to bind, it should return list of details object
        List<Object> list = new ArrayList<Object>();
        return list;
    }

    private void initDataBindings(){

        // for table binding
        BeanProperty<Test, List<Object>> uiBillBeanProperty = BeanProperty.create("objects");
        jTableBinding = SwingBindings.createJTableBinding(UpdateStrategy.READ_WRITE, this, uiBillBeanProperty, billTable);

        BeanProperty<Test, Float> uiBillItemBeanProperty_3 = BeanProperty.create("quantity"); // property need to show 
        jTableBinding.addColumnBinding(uiBillItemBeanProperty_3).setColumnName("Qty");
        // can create multiple property like this 

    }
}

优点:

1. 自动计算列表大小。无需更新，但是当您使用普通 jlabel 时，您必须创建要显示的 jlabel 数量 但不知道尺寸。
2. 您可以在类内部绑定(bind)属性(变量)。

请注意，您还可以根据您可以使用您想要的条件来使用 GlazedLists 绑定(bind)。

下面是 Jlabel 绑定(bind)的代码，

  public class Test extends JPanel{

    private JLabel lblName;
    Details details;

    public Test(){
        lblName = new JLabel();
        add(lblName);

        init();
        initBinding();
    }
    private void init() {

        String sql = "SELECT * FROM details limit 1";
        try
        {
        con = Db.getConnection();
        pst = con.prepareStatement(sql);
        rs = pst.executeQuery();

        details = (Details) rs;
        }catch(Exception e){
            e.printStackTrace();
        }
    }


    private void initBinding(){
        BeanProperty<Details, Srting> beanProperty = BeanProperty.create("name");
        BeanProperty<JLabel, String> jTextFieldBeanProperty = BeanProperty.create("text");
        AutoBinding<Details, String, JLabel, String> autoBinding_20 = Bindings.createAutoBinding(UpdateStrategy.READ_WRITE, details, beanProperty, lblName, jTextFieldBeanProperty);
        autoBinding_20.bind();

        // can bind variables 
    }

}

class Details(){

    private Stirng name;

    private final PropertyChangeSupport propertyChangeSupport = new PropertyChangeSupport(
            this);

    public void addPropertyChangeListener(PropertyChangeListener listener) {
        propertyChangeSupport.addPropertyChangeListener(listener);
    }

    public void addPropertyChangeListener(String propertyName,
            PropertyChangeListener listener) {
        propertyChangeSupport.addPropertyChangeListener(propertyName, listener);
    }

    public void removePropertyChangeListener(PropertyChangeListener listener) {
        propertyChangeSupport.removePropertyChangeListener(listener);
    }

    public void removePropertyChangeListener(String propertyName,
            PropertyChangeListener listener) {
        propertyChangeSupport.removePropertyChangeListener(propertyName,
                listener);

    }

    protected void firePropertyChange(String propertyName, Object oldValue,
            Object newValue) {
        propertyChangeSupport.firePropertyChange(propertyName, oldValue,
                newValue);

    }
}