我正在編寫一個簡單的圖表，您可以在 x、y 軸上顯示一些點。public class GraphPlotter extends JPanel {    private static final long serialVersionUID = 1L;    /** Default frame size X for frame in pixels */    private final int DEFAULT_FRAME_SIZE_X = 800;    /** Default frame size Y for frame in pixels */    private final int DEFAULT_FRAME_SIZE_Y = 600;    /** Padding to Frame */    private final int PAD = 30;    /** Radius of dot */    private final int DOT_RADIUS = 3;    /** Padding of label */    private final int LABEL_PAD = 10;    /** Height of label */    private final int LABEL_HEIGHT = 10;    /** Width of label */    private final int LABEL_WIDTH = 100;    /** Max value for x to print */    private int maxValueForX;    /** Scale factor depending to y*/    private int maxValueForY;    /** Label for the x axis */    private String labelForX = "time";    /** Label for the y axis */    private String labelForY;    /**     * List with points to draw. It holds the y coordinates of points. x     * coordinates are spaced     */    private List<Integer> dataPoints = new ArrayList<>();    /**     *      * Constructor of this class     *      */    public GraphPlotter(ArrayList<Integer> dataPoints, String labelForY) {        this.dataPoints = dataPoints;        this.maxValueForX = dataPoints.size();        this.maxValueForY = Collections.max(dataPoints);        this.labelForY = labelForY;        JFrame f = new JFrame();        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);        f.getContentPane().add(this);        f.setSize(this.DEFAULT_FRAME_SIZE_X + PAD, this.DEFAULT_FRAME_SIZE_Y + PAD);        f.setLocationRelativeTo(null);        f.setVisible(true);    }標簽在應用程序啟動時顯示。如果我調整應用程序窗口的大小，標簽將顯示在整個窗口中。（見截圖）如何避免標簽重復？我假設，在窗口重新粉刷后，程序會在面板中添加相同的標簽。如果我寫add(jLabelY);repaint();在該paintComponent()方法中，此錯誤發生在應用程序啟動時。我也嘗試將面板放入一個FlowLayout，但沒有做任何更改。