如何将数据库中的列值获取到jLabel

Posted 2021-04-03

在我的数据库表中，有一个包含不同数据的列。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

现在我有一个空的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在标签中？插入新数据时，需要创建包含数据的新jLabel。

我尝试了什么。

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"));
        }
    }
}

答案

如果您使用Table，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. 列表大小自动计算。没有必要更新，但当你去正常的jlabel你必须创建jlabel想要显示但不知道大小的数量。
2. 您可以绑定类中的属性（变量）。

请注意，您可以根据您可以使用您想要的条件使用GlazedLists进行绑定。

下面是Jlabel绑定的代码，

  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);

    }
}