JTextArea自动换行以及设置滚动条

应将JTextArea置于JScrollPanel中
若要使只有垂直滚动条而没有水平滚动条，使用JTextArea.setLineWrap(true),自动换行。

文本换行代码片段如下：

JTextArea adressTextArea = new JTextArea(11, 35);
//设置自动换行
adressTextArea.setLineWrap(true);
//定义带滚动条的panel，并将JTextArea存入到panel中，使textarea具有滚动条显示功能。
JScrollPane scrollpane = new JScrollPane(adressTextArea);
//取消显示水平滚动条
scrollpane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
//显示垂直滚动条
scrollpane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);

以下为个人测试画的一个简单页面，仅供参考：

 package JFrameTest;

 import java.awt.BorderLayout;

 @SuppressWarnings("all")
 public class ApplyCertTest extends JFrame {

     private JPanel contentPane;

     /**
      * Launch the application.
      */
     public static void main(String[] args) {
         EventQueue.invokeLater(new Runnable() {
             public void run() {
                 try {
                     ApplyCertTest frame = new ApplyCertTest();
                     frame.setVisible(true);
                     frame.setTitle("申请新许可");
                     frame.getContentPane().setLayout(null);
                 } catch (Exception e) {
                     e.printStackTrace();
                 }
             }
         });
     }

     /**
      * Create the frame.
      */
     public ApplyCertTest() {
         setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         //setResizable决定了窗体是否可以放大。true则可以最大化，false则不可变
         setResizable(false);
         setBounds(100, 100, 510, 520);
         contentPane = new JPanel();
         contentPane.setLayout(new FlowLayout(FlowLayout.LEFT));

         getContentPane().add(contentPane, BorderLayout.NORTH);

         JLabel lblNewLabel = new JLabel("    生成新的许可需填写下列信息:");
         lblNewLabel.setLabelFor(contentPane);
         contentPane.add(lblNewLabel);

         JPanel lPanel = new JPanel();
         lPanel.setBorder (BorderFactory.createTitledBorder ("申请文件信息"));
         lPanel.setLayout(new BorderLayout(5, 0));
         getContentPane().add(lPanel);

         //用户名称
         JPanel mlPanel = new JPanel();
         mlPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
         JLabel userName = new JLabel("用户名称:        ");
         mlPanel.add(userName);
         JTextField userTextField = new JTextField(35);
         mlPanel.add(userTextField);

         //公司名称
         mlPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
         JLabel companyName = new JLabel("公司名称:        ");
         mlPanel.add(companyName);
         JTextField companyTextField = new JTextField(35);
         mlPanel.add(companyTextField);
         lPanel.add(mlPanel);

         //电话号码
         mlPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
         JLabel phone = new JLabel("电话号码:        ");
         mlPanel.add(phone);
         JTextField phoneTextField = new JTextField(35);
         mlPanel.add(phoneTextField);
         lPanel.add(mlPanel);

         //电子邮件
         mlPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
         JLabel email = new JLabel("电子邮件:        ");
         mlPanel.add(email);
         JTextField emailTextField = new JTextField(35);
         mlPanel.add(emailTextField);
         lPanel.add(mlPanel);

         //联系地址
         mlPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
         JLabel adress = new JLabel("联系地址:        ");
         mlPanel.add(adress);
         //JTextField adressTextField = new JTextField(35);
         JTextArea adressTextArea = new JTextArea(11, 35);
         //设置自动换行
         adressTextArea.setLineWrap(true);
         //定义带滚动条的panel，并将JTextArea存入到panel中，使textarea具有滚动条显示功能。
         JScrollPane scrollpane = new JScrollPane(adressTextArea);
         //取消显示水平滚动条
         scrollpane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
         //显示垂直滚动条
         scrollpane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
         mlPanel.add(scrollpane);
         lPanel.add(mlPanel);

         //适用IP
         mlPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
         JLabel ipLabel = new JLabel("适用IP:             ");
         mlPanel.add(ipLabel);
         JTextField ipTextField = new JTextField(35);
         mlPanel.add(ipTextField);
         lPanel.add(mlPanel);

         //适用mac地址
         mlPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
         JLabel macLabel = new JLabel("适用mac地址:");
         mlPanel.add(macLabel);
         JTextField macTextField = new JTextField(35);
         mlPanel.add(macTextField);
         lPanel.add(mlPanel);

         //使用时限(天)
         mlPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
         JLabel dayLimit = new JLabel("使用时限(天): ");
         mlPanel.add(dayLimit);
         JTextField dayLimitTextField = new JTextField(35);
         mlPanel.add(dayLimitTextField);
         lPanel.add(mlPanel);

         JPanel bPanel = new JPanel();
         bPanel.setLayout(new FlowLayout(FlowLayout.RIGHT));
         JButton saveButton = new JButton("保存");
         JButton resetButton = new JButton("重置");
         JButton quitButton = new JButton("退出");
         bPanel.add(saveButton);
         bPanel.add(resetButton);
         bPanel.add(quitButton);

         getContentPane().add(bPanel, BorderLayout.SOUTH);

     }
 }