Java Sqlite登录授权失败

我编写了一个所谓的“无错误”代码，但在使用该应用程序时遇到了一些问题。 这是我的密码：

import java.sql.*;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Login implements ActionListener {

    Connection conn1 = null;
    Statement stmt1 = null;

    Connection conn2 = null;
    Statement stmt2 = null;

    Connection conn3 = null;
    Statement stmt3 = null;

    JFrame frame = new JFrame("Login Window");
    JPanel startPanel = new JPanel();
    JPanel adminPanel = new JPanel();
    JPanel engineerPanel = new JPanel();

    JButton adminLogin = new JButton("Admin Login");
    JButton engineerLogin = new JButton("Engineer Login");

    JTextField adminUsername = new JTextField();
    JPasswordField adminPassword = new JPasswordField();
    JButton adminLog = new JButton("Login");
    JButton adminBack = new JButton("Go Back");

    JComboBox engineerUsername = new JComboBox();
    JPasswordField engineerPassword = new JPasswordField();
    JButton engineerLog = new JButton("Login");
    JButton engineerBack = new JButton("Go Back");

    public Login(){
        //Establishing connection with database
        conn1 = sqliteConnection.dbConnector();

        frame.setLayout(new GridLayout(1, 1));

        /*
         Setting up the startPanel 
         */
        startPanel.setLayout(new GridLayout(3, 3, 15, 15));

        // Row 1
        startPanel.add(new JLabel(" "));

        JLabel loginType = new JLabel("     SELECT LOGIN TYPE");
        loginType.setFont(new Font("Tahoma", Font.BOLD, 12));
        startPanel.add(loginType);

        startPanel.add(new JLabel(" "));

        // Row 2
        startPanel.add(new JLabel(" "));
        startPanel.add(adminLogin);
        startPanel.add(new JLabel(" "));

        // Row 3
        startPanel.add(new JLabel(" "));
        startPanel.add(engineerLogin);
        startPanel.add(new JLabel(" "));

        adminLogin.addActionListener(this);
        engineerLogin.addActionListener(this);

        /* 
         Setting up adminPanel
         */
        adminPanel.setLayout(new GridLayout(4, 2, 15, 15));

        // Row 1
        adminPanel.add(new JLabel("Admin Login"));
        adminPanel.add(new JLabel(" "));

        // Row 2
        adminPanel.add(new JLabel("Username"));
        adminPanel.add(adminUsername);

        // Row 3
        adminPanel.add(new JLabel("Password"));
        adminPanel.add(adminPassword);

        // Row 4
        adminPanel.add(adminLog);
        adminPanel.add(adminBack);

        adminLog.addActionListener(this);
        adminBack.addActionListener(this);

        //Initial Visibility False
        adminPanel.setVisible(false);

        /* 
         Setting up engineerPanel
         */
        engineerPanel.setLayout(new GridLayout(4, 2, 15, 15));

        // Row 1
        engineerPanel.add(new JLabel("Engineer Login"));
        engineerPanel.add(new JLabel(" "));

        // Row 2

        try{
              Class.forName("org.sqlite.JDBC");
              conn1.setAutoCommit(false);
              stmt1 = conn1.createStatement();
              ResultSet rs1 = stmt1.executeQuery( "SELECT * FROM EngineerData;" );

              List<String> engineerNamesList = new ArrayList<String>();

              while ( rs1.next() ){
                  String name = rs1.getString("Name");
                  engineerNamesList.add(name);
              }

              // Converting array list to array
              String[] engineerNames = new String[engineerNamesList.size()];
              engineerNamesList.toArray(engineerNames);

              // Adding array into combo-box
              for (String en : engineerNames){
                  engineerUsername.addItem(en);
              }

              rs1.close();
              stmt1.close();
              conn1.close();
        }
        catch ( Exception e1 ) {
            JOptionPane.showMessageDialog(null, e1);    
        }

        engineerPanel.add(new JLabel("Engineer Name"));
        engineerPanel.add(engineerUsername);

        // Row 3
        engineerPanel.add(new JLabel("Password"));
        engineerPanel.add(engineerPassword);

        // Row 4
        engineerPanel.add(engineerLog);
        engineerPanel.add(engineerBack);

        engineerLog.addActionListener(this);
        engineerBack.addActionListener(this);

        //Initial Visibility False
        engineerPanel.setVisible(false);



        frame.setSize(500, 200);
        frame.setResizable(false);
        frame.add(startPanel);
        frame.setVisible(true);

    }

    //Method to convert integar array list to integar array
    public int[] convertIntegers(List<Integer> integers)
    {
        int[] ret = new int[integers.size()];
        for (int i=0; i < ret.length; i++)
        {
            ret[i] = integers.get(i).intValue();
        }
        return ret;
    }

    //Admin login method
    public void adminLogin(){

        String adminUser = adminUsername.getText();
        String adminPass = adminPassword.getText();

        String adminUserDB = null;
        String adminPassDB = null;

        conn2 = sqliteConnection.dbConnector();

        try{
              Class.forName("org.sqlite.JDBC");
              conn2.setAutoCommit(false);
              stmt2 = conn2.createStatement();
              ResultSet rs2 = stmt2.executeQuery( "SELECT * FROM AdminData;" );

              adminUserDB = rs2.getString("Username");
              adminPassDB = rs2.getString("Password");

              conn2.close();
              stmt2.close();
              rs2.close();
        }
        catch (Exception e2){

        }

        if (adminUser.equals(adminUserDB) && adminPass.equals(adminPassDB)){
            AdminClass ac = new AdminClass();

            frame.dispose();
        }

        else if (adminUser.equals(adminUserDB) && adminPass != adminPassDB){
            JOptionPane.showMessageDialog(null, "Incorrect Password.\nPlease enter again.");
        }

        else if (adminUser != adminUserDB && adminPass.equals(adminPassDB)){
            JOptionPane.showMessageDialog(null, "Incorrect Username.\nPlease enter again.");
        }

        else if (adminUser != adminUserDB && adminPass != adminPassDB){
            JOptionPane.showMessageDialog(null, "Incorrect Username and Password.\nPlease enter again.");
        }


    }

    //Engineer login method
    public void engineerLogin(){

        String engineerUser = engineerUsername.getSelectedItem().toString();
        String engineerPass = engineerPassword.getText();

        List<String> engineerNamesList = new ArrayList<String>();
        List<String> engineerPasswordsList = new ArrayList<String>();
        ArrayList<Integer> uniqueIDList = new ArrayList<Integer>();

        conn3 = sqliteConnection.dbConnector();

        try{
              Class.forName("org.sqlite.JDBC");
              conn3.setAutoCommit(false);
              stmt3 = conn3.createStatement();
              ResultSet rs3 = stmt3.executeQuery( "SELECT * FROM EngineerData;" );

              while ( rs3.next() ){

                  int uniqueId = rs3.getInt("UniqueId");
                  String engineerUserDB = rs3.getString("Name");
                  String engineerPassDB = rs3.getString("Password");

                  //Adding data from database to variables that exist in our code
                  engineerNamesList.add(engineerUserDB);
                  engineerPasswordsList.add(engineerPassDB);
                  uniqueIDList.add(uniqueId);

              }

              conn3.close();
              stmt3.close();
              rs3.close();
        }
        catch (Exception e3){

        }

        // Creating usable arrays from array lists
        String[] engineerNames = new String[engineerNamesList.size()];
        engineerNamesList.toArray(engineerNames);

        String[] engineerPasswords = new String[engineerPasswordsList.size()];
        engineerPasswordsList.toArray(engineerPasswords);

        int[] uniqueIDs = convertIntegers(uniqueIDList);

        for (int i = 0; i < engineerNames.length; i++){


            boolean condition = (engineerUser.equals(engineerNames[i]) && engineerPass.equals(engineerPasswords[i]));

            if (condition){

                frame.dispose();

                EngineerPanel ep = new EngineerPanel();

                //This ID is the identifier of the engineer
                //This will be used to generate data only for his particular project
                ep.setUniqueID(uniqueIDs[i]);

                break;
            }

            else if (i>= 1 && condition != true){
                JOptionPane.showMessageDialog(null, "Incorrect Password");
                continue;
            }

        }

    }

    public void actionPerformed(ActionEvent e){

        if (e.getSource() == adminLogin){

            startPanel.setVisible(false);
            frame.remove(startPanel);
            frame.add(adminPanel);
            adminPanel.setVisible(true);


        }

        if (e.getSource() == engineerLogin){

            startPanel.setVisible(false);
            frame.remove(startPanel);
            frame.add(engineerPanel);
            engineerPanel.setVisible(true);
        }

        if (e.getSource() == adminBack){

            adminUsername.setText(null);
            adminPassword.setText(null);
            adminPanel.setVisible(false);
            frame.remove(adminPanel);
            frame.add(startPanel);
            startPanel.setVisible(true);
        }

        if (e.getSource() == engineerBack){

            engineerPassword.setText(null);
            engineerPanel.setVisible(false);
            frame.remove(engineerPanel);
            frame.add(startPanel);
            startPanel.setVisible(true);
        }

        if (e.getSource() == adminLog){
            adminLogin();
        }

        if (e.getSource() == engineerLog){
            engineerLogin();
        }
    }
}

import java.sql.*；
导入java.util.ArrayList；
导入java.util.List；
导入javax.swing.*；
导入java.awt.*；
导入java.awt.event.*；
公共类登录实现ActionListener{
连接conn1=null；
语句stmt1=null；
连接conn2=null；
语句stmt2=null；
连接conn3=null；
语句stmt3=null；
JFrame=newjframe（“登录窗口”）；
JPanel startPanel=新的JPanel（）；
JPanel adminPanel=新的JPanel（）；
JPanel engineerPanel=新的JPanel（）；
JButton adminLogin=新JButton（“管理员登录”）；
JButton engineerLogin=新JButton（“工程师登录”）；
JTextField adminUsername=新的JTextField（）；
JPasswordField adminPassword=新的JPasswordField（）；
JButton adminLog=新JButton（“登录”）；
JButton adminBack=新JButton（“返回”）；
JComboBox engineerUsername=新的JComboBox（）；
JPasswordField engineerPassword=新的JPasswordField（）；
JButton engineerLog=新JButton（“登录”）；
JButton engineerBack=新JButton（“返回”）；
公共登录（）{
//建立与数据库的连接
conn1=sqliteConnection.dbConnector（）；
frame.setLayout（新的GridLayout（1,1））；
/*
设置startPanel
*/
startPanel.setLayout（新网格布局（3,3,15,15））；
//第1行
startPanel.add（新的JLabel（“”）；
JLabel loginType=新的JLabel（“选择登录类型”）；
setFont（新字体（“Tahoma”，Font.BOLD，12））；
startPanel.add（登录类型）；
startPanel.add（新的JLabel（“”）；
//第2排
startPanel.add（新的JLabel（“”）；
startPanel.add（adminLogin）；
startPanel.add（新的JLabel（“”）；
//第3排
startPanel.add（新的JLabel（“”）；
startPanel.add（engineerLogin）；
startPanel.add（新的JLabel（“”）；
adminLogin.addActionListener（这个）；
engineerLogin.addActionListener（此）；
/* 
设置adminPanel
*/
setLayout（新的GridLayout（4,2,15,15））；
//第1行
添加（新的JLabel（“管理员登录”）；
adminPanel.add（新的JLabel（“”）；
//第2排
adminPanel.add（新的JLabel（“用户名”））；
adminPanel.add（adminUsername）；
//第3排
adminPanel.add（新的JLabel（“密码”））；
adminPanel.add（adminPassword）；
//第4排
adminPanel.add（adminLog）；
adminPanel.add（adminBack）；
adminLog.addActionListener（这个）；
addActionListener（这个）；
//初始可见性错误
adminPanel.setVisible（false）；
/* 
设置工程师小组
*/
engineerPanel.setLayout（新网格布局（4,2,15,15））；
//第1行
添加（新JLabel（“工程师登录”）；
engineerPanel.add（新的JLabel（“”）；
//第2排
试一试{
Class.forName（“org.sqlite.JDBC”）；
conn1.设置自动提交（错误）；
stmt1=conn1.createStatement（）；
ResultSet rs1=stmt1.executeQuery（“从EngineerData中选择*”；
List engineerNamesList=新建ArrayList（）；
while（rs1.next（））{
字符串名称=rs1.getString（“名称”）；
工程师名称列表。添加（名称）；
}
//将数组列表转换为数组
String[]engineerNames=新字符串[engineerNamesList.size（）]；
工程师姓名列表。toArray（工程师姓名）；
//将数组添加到组合框中
for（字符串en:engineerNames）{
engineerUsername.addItem（英语）；
}
rs1.close（）；
stmt1.close（）；
conn1.close（）；
}
捕获（异常e1）{
showMessageDialog（null，e1）；
}
添加（新的JLabel（“工程师姓名”）；
engineerPanel.add（engineerUsername）；
//第3排
添加（新的JLabel（“密码”）；
engineerPanel.add（engineerPassword）；
//第4排
engineerPanel.add（engineerLog）；
engineerPanel.add（engineerBack）；
engineerLog.addActionListener（此）；
engineerBack.addActionListener（此）；
//初始可见性错误
engineerPanel.setVisible（假）；
框架设置尺寸（500200）；
frame.setresizeable（false）；
帧。添加（startPanel）；
frame.setVisible（true）；
}
//方法将整数数组列表转换为整数数组
公共整数[]转换器整数（列表整数）
{
int[]ret=new int[integers.size（）]；
对于（int i=0；ifor (int i = 0; i < engineerNames.length; i++){
  boolean condition = ...
  if (condition){
    // OK
  } else {
   // show error
  }
}

boolean ok=false;
for (int i = 0; i < engineerNames.length; i++){
  boolean condition = ...
  ok |= condition;

}
if (ok){
    // OK
} else {
   // show error
}

SELECT * FROM EngineerData where Name=? and Password=?