java图形界面编译出错~新手求助！

RCPjava富客户端应用，swt，这个我就懂的很少了，哈哈哈
package Tes;import java.awt.Color;
import java.awt.Container;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingConstants;class Update extends JFrame implements ActionListener {
JFrame f;
Container cp;
JPanel jp1, jp2, jp3, jp4, jp, jpanelWest;
JButton jbt1, jbt2;// 按钮，确定、取消
JLabel label;// 标签：修改密码
JTextField tf0, tf1, tf2, tf3, tf4, tf5, tf6, tf7, tf8, tf9, tf10;
String sno; Update() {
} Update(String bookno) {
sno = bookno;
f = new JFrame();
cp = f.getContentPane(); // 初始化
jp1 = new JPanel();
jp2 = new JPanel();
jp3 = new JPanel();
jp4 = new JPanel();
jpanelWest = new JPanel();
jp = new JPanel();
jbt1 = new JButton("确定");
jbt2 = new JButton("取消");
int size = 20;
label = new JLabel("修改图书信息", SwingConstants.CENTER);
label.setFont(new Font("修改图书信息", Font.PLAIN, size));// 加粗，字体大小20
label.setForeground(Color.blue);
tf0 = new JTextField(20);
tf1 = new JTextField(20);
tf2 = new JTextField(20);
tf3 = new JTextField(20);
tf4 = new JTextField(20);
tf5 = new JTextField(20);
tf6 = new JTextField(20);
tf7 = new JTextField(20);
tf8 = new JTextField(20);
tf9 = new JTextField(20);
tf10 = new JTextField(20);
// 布局,添加控件
jp1.add(jbt1);
jp1.add(jbt2);
jp1.add(new JLabel("欢迎登陆"));
JPanel jpanel = new JPanel();
jpanel.add(label);
JPanel pp4 = new JPanel();
JPanel jpane4 = new JPanel();
cp.add(jpanel, "North");
JPanel pp2 = new JPanel(new GridLayout(6, 1));
pp4.setLayout(new GridLayout(6, 1));
pp4.add(new JLabel("输入要修改的图书号: ", SwingConstants.RIGHT));
pp2.add(tf0);
pp4.add(new JLabel("原书名: ", SwingConstants.RIGHT));
pp2.add(tf1);
pp4.add(new JLabel("现书名: ", SwingConstants.RIGHT));
pp2.add(tf2);
pp4.add(new JLabel("原单价: ", SwingConstants.RIGHT));
pp2.add(tf3);
pp4.add(new JLabel("现单价: ", SwingConstants.RIGHT));
pp2.add(tf4);
pp4.add(new JLabel("原作者: ", SwingConstants.RIGHT));
pp2.add(tf5);
pp4.add(new JLabel("现作者: ", SwingConstants.RIGHT));
pp2.add(tf6);
pp4.add(new JLabel("原出版社: ", SwingConstants.RIGHT));
pp2.add(tf7);
pp4.add(new JLabel("现出版社: ", SwingConstants.RIGHT));
pp2.add(tf8);
pp4.add(new JLabel("原入库时间: ", SwingConstants.RIGHT));
pp2.add(tf9);
pp4.add(new JLabel("现入库时间: ", SwingConstants.RIGHT));
pp2.add(tf10);
pp2.add(new JLabel());
JPanel jpbutton = new JPanel();
jpbutton.add(jbt1);
jpbutton.add(jbt2);
pp2.add(jpbutton);
cp.add(pp4, "West");
cp.add(pp2, "Center");
cp.add(jpane4, "East");
f.setSize(500, 450);
f.setVisible(true);
jbt1.addActionListener(this);// 注册监听器
jbt2.addActionListener(this);
} public void updateM() {
try {
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
} catch (ClassNotFoundException e) {
System.out.println("加载驱动程序失败!");
}
try {
// 直接使用当前类目录下的数据库文件
Connection con = DriverManager.getConnection(
"jdbc:sqlserver://localhost:1433; DatabaseName=Book", "sa",
"xuqianqian");
Statement sql = con.createStatement();
String utf0 = tf0.getText().trim();
String queryMima = "select * from book where 图书号='" + utf0 + "'";
ResultSet rs = sql.executeQuery(queryMima);
if (rs.next()) {
String newname = tf2.getText().trim();
String newcost = tf4.getText().trim();
String newauthor = tf6.getText().trim();
String newchuban = tf8.getText().trim();
String newruku = tf10.getText().trim();
String s = "update book set 图书名='" + newname + "'，作者='"
+ newauthor + "',单价='" + newcost + "',出版社='"
+ newchuban + "',入库时间='" + newruku + "' where 图书号 ='"
+ utf0 + "'";
sql = con.createStatement();
int update = sql.executeUpdate(s);
if (update == 1) {
JOptionPane.showMessageDialog(f, "图书信息修改成功！");
}
con.close();
f.repaint();
} else {
JOptionPane.showMessageDialog(null, "该用户不存在", "警告！",
JOptionPane.YES_NO_OPTION);
}
tf0.setText("");
tf1.setText("");
tf2.setText("");
tf3.setText("");
tf4.setText("");
tf5.setText("");
tf6.setText("");
tf7.setText("");
tf8.setText("");
tf9.setText("");
tf10.setText("");
} catch (SQLException g) {
System.out.println("E Code" + g.getErrorCode());
System.out.println("E M" + g.getMessage());
}
} public void actionPerformed(ActionEvent e) {
String cmd = e.getActionCommand();
if (cmd.equals("确定")) {
if (tf0.getText().equals("") || tf1.getText().equals("")
|| tf2.getText().equals("") || tf3.getText().equals("")
|| tf4.getText().equals("") || tf5.getText().equals("")
|| tf6.getText().equals("") || tf7.getText().equals("")
|| tf8.getText().equals("") || tf9.getText().equals("")
|| tf10.getText().equals("")) {
JOptionPane.showMessageDialog(null, "请填写图书的所有信息", "提示",
JOptionPane.YES_NO_OPTION);
return;
}
} else if (cmd.equals("取消"))
f.hide();
} public static void main(String[] args) {
new Update("");
}
}
少new个tf0。仔细看下。。
String newname = tf2.getText().trim();
String newcost = tf4.getText().trim();
String newauthor = tf6.getText().trim();
String newchuban = tf8.getText().trim();
String newruku = tf10.getText().trim();
先判断一下  getText() 是不是null

调试易

java图形界面编译出错~新手求助！

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