Java JDBC 登录表单

Question

我似乎无法在我的 Java JTextfield 和 Passwordfield 上获取密码和用户名，我试图做的是比较用户输入并检查它们是否将用户名和密码存储在数据库中，如果是的话它们会已登录，但问题是我的密码字段上的 getText() 已被弃用，我该如何解决这个问题？？

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.*;
import javax.swing.JOptionPane;

public class Login extends JFrame {

private JLabel nameLabel;
private JLabel passwordLabel;
private JTextField nameText;
private JPasswordField passwordField;
private JButton submitButton;
Connection conn = null;

public Login(){

super("Log in!");
setLayout(new FlowLayout());
setVisible(true);
setSize(178,190);
setDefaultCloseOperation(EXIT_ON_CLOSE);

nameLabel = new JLabel("User ID: ");
add(nameLabel);

nameText = new JTextField(10);
add(nameText);

passwordLabel = new JLabel("Password: ");
add(passwordLabel);

passwordField = new JPasswordField(10);
add(passwordField);

submitButton = new JButton("Submit");
add(submitButton);

ButtonHandler handler = new ButtonHandler();
submitButton.addActionListener(handler);
}

private class ButtonHandler implements ActionListener{

public void actionPerformed(ActionEvent e){

String user = nameText.getText();
String pass = passwordField.getText();
try{
Jdbc test = new Jdbc();
conn = test.dbConn();
String query = "SELECT employee_ID,employee_password FROM user where ='"+user+"'";

}catch(Exception eee){
eee.printStackTrace();
}
}
}
}

Answer 1

使用getPassword()而不是 getText() 方法。

  char []passChars=passwordField.getPassword();
   if(passChars!=null) { 
       String pass=new String(passChars);
       String sql="SELECT employee_ID,employee_password FROM user 
                             where user=? and employee_password=?";
       PreparedStatement ps=conn.prepareStatement(sql);
       ps.setString(1,user);
       ps.setString(2,pass);
       ResultSet rs=ps.executeQuery();
       if(rs.next()) {
          //found
       }
       else{
          //not found
       }
       rs.close();
       ps.close();
       conn.close();
   }

值得注意的一点是不要使用硬编码的sql语句。使用PreparedStatement 对字符串进行转义以防止SQL 注入(inject)。