用代码添加的按钮为何显示不出来？而用GUI设计器却可以？

import java.sql.ResultSet;



/*

 * myJPanel.java

 *

 * Created on 2008年10月30日, 下午10:36

 */

import javax.swing.JRadioButton;



/**

 *

 * @author  Kuvon

 */

public class MyJPanel extends javax.swing.JPanel {



    DBConnection myDBConnection;

    ResultSet rsDB;

    int rsRowNumber;

    //JRadioButton starButton;



    /** Creates new form myJPanel */

    public MyJPanel() {     

        

        initComponents();

        myDBConnection = new DBConnection();

        myDBConnection.dbConnection();

        String strSQL = "SELECT * FROM StarInfo";

        rsDB = myDBConnection.excuteSQL(strSQL);

        try {

            while (rsDB.next()) {

                System.out.println(rsDB.getString("starName"));

                System.out.println(rsDB.getString("starPic"));

            }

            rsDB.last();

            rsRowNumber = rsDB.getRow();

            System.out.println(rsRowNumber);

        } catch (Exception e) {

            System.out.println(e.getMessage());

        }



        try {

            rsDB.first();

            JRadioButton[] starButton = new JRadioButton[rsRowNumber];

            //starButton = new JRadioButton[rsRowNumber];

            for(int i = 0;i < rsRowNumber;i++){

                starButton[i] = new JRadioButton(rsDB.getString("starName"));

                rsDB.next();

                add(starButton[i]);

            }

            //starButton.setText(/*rsDB.getString("starName")*/"TestButton");



            /*

            for (int i = 0; i < rsRowNumber - 1; i++) {

                starButton.setText(rsDB.getString("starName"));

            }

            */

        } catch (Exception e) {

            System.out.println(e.getMessage());

        }

    }



    /** This method is called from within the constructor to

     * initialize the form.

     * WARNING: Do NOT modify this code. The content of this method is

     * always regenerated by the Form Editor.

     */

    @SuppressWarnings("unchecked")

    // <editor-fold defaultstate="collapsed" desc="Generated Code">

    private void initComponents() {



        buttonGroupPicture = new javax.swing.ButtonGroup();

        jLabelTitle = new javax.swing.JLabel();

        jPanelPicture = new javax.swing.JPanel();

        jLabelPicture = new javax.swing.JLabel();

        jPanelName = new javax.swing.JPanel();



        jLabelTitle.setFont(new java.awt.Font("楷体", 0, 36)); // NOI18N

        jLabelTitle.setForeground(new java.awt.Color(255, 102, 102));

        jLabelTitle.setText("第29届国际奥林匹克运动会冠军风采");



        jPanelPicture.setBorder(javax.swing.BorderFactory.createEtchedBorder());



        jLabelPicture.setText("图片将在这里显示");



        javax.swing.GroupLayout jPanelPictureLayout = new javax.swing.GroupLayout(jPanelPicture);

        jPanelPicture.setLayout(jPanelPictureLayout);

        jPanelPictureLayout.setHorizontalGroup(

            jPanelPictureLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanelPictureLayout.createSequentialGroup()

                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)

                .addComponent(jLabelPicture, javax.swing.GroupLayout.PREFERRED_SIZE, 325, javax.swing.GroupLayout.PREFERRED_SIZE)

                .addContainerGap())

        );

        jPanelPictureLayout.setVerticalGroup(

            jPanelPictureLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanelPictureLayout.createSequentialGroup()

                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)

                .addComponent(jLabelPicture, javax.swing.GroupLayout.PREFERRED_SIZE, 461, javax.swing.GroupLayout.PREFERRED_SIZE)

                .addContainerGap())

        );



        jPanelName.setBorder(javax.swing.BorderFactory.createTitledBorder("请选择姓名"));



        javax.swing.GroupLayout jPanelNameLayout = new javax.swing.GroupLayout(jPanelName);

        jPanelName.setLayout(jPanelNameLayout);

        jPanelNameLayout.setHorizontalGroup(

            jPanelNameLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

            .addGap(0, 313, Short.MAX_VALUE)

        );

        jPanelNameLayout.setVerticalGroup(

            jPanelNameLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

            .addGap(0, 416, Short.MAX_VALUE)

        );



        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);

        this.setLayout(layout);

        layout.setHorizontalGroup(

            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

            .addGroup(layout.createSequentialGroup()

                .addContainerGap(100, Short.MAX_VALUE)

                .addComponent(jLabelTitle)

                .addGap(78, 78, 78))

            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()

                .addContainerGap(29, Short.MAX_VALUE)

                .addComponent(jPanelName, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)

                .addGap(18, 18, 18)

                .addComponent(jPanelPicture, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)

                .addGap(33, 33, 33))

        );

        layout.setVerticalGroup(

            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()

                .addContainerGap(22, Short.MAX_VALUE)

                .addComponent(jLabelTitle)

                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

                    .addGroup(layout.createSequentialGroup()

                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)

                        .addComponent(jPanelPicture, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))

                    .addGroup(layout.createSequentialGroup()

                        .addGap(29, 29, 29)

                        .addComponent(jPanelName, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)))

                .addGap(24, 24, 24))

        );

    }// </editor-fold>



    // Variables declaration - do not modify

    private javax.swing.ButtonGroup buttonGroupPicture;

    private javax.swing.JLabel jLabelPicture;

    private javax.swing.JLabel jLabelTitle;

    private javax.swing.JPanel jPanelName;

    private javax.swing.JPanel jPanelPicture;

    // End of variables declaration

}

        try {

            rsDB.first();

            JRadioButton[] starButton = new JRadioButton[rsRowNumber];

            //starButton = new JRadioButton[rsRowNumber];

            for(int i = 0;i < rsRowNumber;i++){

                starButton[i] = new JRadioButton(rsDB.getString("starName"));

                rsDB.next();

                add(starButton[i]);

            }

            //starButton.setText(/*rsDB.getString("starName")*/"TestButton");



            /*

            for (int i = 0; i < rsRowNumber - 1; i++) {

                starButton.setText(rsDB.getString("starName"));

            }

            */

        } catch (Exception e) {

            System.out.println(e.getMessage());

        }