scrollpane问题，高手请进！！！

Question

1.放在ScrollPanel中的组件一般不需要设置大小.
2.
    jScrollPane1.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
    jScrollPane1.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);

Answer 1

我试过还是不行，效果是全屏时jScrollPane外面增加了垂直和水平的滚动条，未全屏时还是没滚动条出现。

Answer 2

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;public class Frame1 extends JFrame
{
    JPanel contentPane;
    BorderLayout borderLayout1 = new BorderLayout();
    JScrollPane jScrollPane1 = new JScrollPane();
    JTextArea jTextArea1 = new JTextArea();    //Construct the frame
    public Frame1()
    {
        enableEvents(AWTEvent.WINDOW_EVENT_MASK);
        try
        {
            jbInit();
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
    }
    //Component initialization
    private void jbInit() throws Exception
    {
        contentPane = (JPanel) this.getContentPane();
        contentPane.setLayout(borderLayout1);
        this.setSize(new Dimension(400, 300));
        this.setTitle("Frame Title");
        jTextArea1.setText("jTextArea1");
        contentPane.add(jScrollPane1, BorderLayout.CENTER);
        jScrollPane1.getViewport().add(jTextArea1, null);
    }
    //Overridden so we can exit when window is closed
    protected void processWindowEvent(WindowEvent e)
    {
        super.processWindowEvent(e);
        if (e.getID() == WindowEvent.WINDOW_CLOSING)
        {
            System.exit(0);
        }
    }
}
///////////////////////////////////
import javax.swing.UIManager;
import java.awt.*;public class Application1
{
    boolean packFrame = false;    //Construct the application
    public Application1()
    {
        Frame1 frame = new Frame1();
        //Validate frames that have preset sizes
        //Pack frames that have useful preferred size info, e.g. from their layout
        if (packFrame)
        {
            frame.pack();
        }
        else
        {
            frame.validate();
        }
        //Center the window
        Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
        Dimension frameSize = frame.getSize();
        if (frameSize.height > screenSize.height)
        {
            frameSize.height = screenSize.height;
        }
        if (frameSize.width > screenSize.width)
        {
            frameSize.width = screenSize.width;
        }
        frame.setLocation((screenSize.width - frameSize.width) / 2, (screenSize.height - frameSize.height) / 2);
        frame.setVisible(true);
    }
    //Main method
    public static void main(String[] args)
    {
        try
        {
            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
        new Application1();
    }
}

Answer 3

有关滚动条和文本的就这些 
JEditTextArea jEditTextArea = new JEditTextArea();
        jEditTextArea.setText("");
   jEditTextArea.getDocument().addDocumentListener(new
        EditorPanel_jEditTextArea_DocumentListener(this));
  
  JScrollPane jScrollPane2 = new JScrollPane();
    jTabbedPane1.add(jScrollPane2, "jsp source");
    jScrollPane2.getViewport().add(jEditTextArea, null);