資料庫簡單操作—註冊和登入例項
阿新 • • 發佈：2019-02-11
本例是建立使用者註冊和登入的資料庫操作，通過Swing元件實現註冊和登入介面的實現。
註冊
功能實現
註冊實現：
判斷使用者名稱輸入是否合法：
判斷密碼輸入是否合法：
判斷兩次密碼輸入是否一致：
註冊程式碼
//SQLManager類
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
//採用單例設計模式
public class SQLManager {
private //登入介面
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JTextField;
import javax.swing.JLabel;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.awt.event.ActionEvent;
public class MySQL extends JFrame {
private JPanel contentPane;
private JTextField textFieldUserName;
private JTextField textFieldPassword;
private JTextField textFieldPasswordAgain;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
MySQL frame = new MySQL();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public MySQL() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 453, 395);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
textFieldUserName = new JTextField();
textFieldUserName.setBounds(125, 77, 133, 21);
contentPane.add(textFieldUserName);
textFieldUserName.setColumns(10);
JLabel lblNewLabelUser = new JLabel("使用者名稱：");
lblNewLabelUser.setBounds(40, 80, 54, 15);
contentPane.add(lblNewLabelUser);
textFieldPassword = new JTextField();
textFieldPassword.setBounds(125, 120, 133, 21);
contentPane.add(textFieldPassword);
textFieldPassword.setColumns(10);
JLabel lblNewLabelPassword = new JLabel("密碼：");
lblNewLabelPassword.setBounds(40, 123, 54, 15);
contentPane.add(lblNewLabelPassword);
textFieldPasswordAgain = new JTextField();
textFieldPasswordAgain.setBounds(125, 175, 133, 21);
contentPane.add(textFieldPasswordAgain);
textFieldPasswordAgain.setColumns(10);
JLabel lblNewLabelPasswordAgain = new JLabel("確認密碼：");
lblNewLabelPasswordAgain.setBounds(40, 178, 75, 15);
contentPane.add(lblNewLabelPasswordAgain);
JButton btnNewButton = new JButton("提交");
btnNewButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
//建立一個manager物件。
SQLManager manager = SQLManager.newInstance();
Statement statement = manager.getStatement();
String userName = textFieldUserName.getText();
//正則表示式判斷使用者名稱是否合法
Pattern p_userName = Pattern.compile("^\\w+$");
Matcher m_userName = p_userName.matcher(userName);
boolean b_userName = m_userName.matches();
String password = textFieldPassword.getText();
//正則表示式判斷密碼是否合法
Pattern p_password = Pattern.compile("^\\w+$");
Matcher m_password = p_password.matcher(password);
boolean b_password = m_password.matches();
String passwordAgain = textFieldPasswordAgain.getText();
//正則表示式判斷密碼是否合法
Pattern p_passwordAgain = Pattern.compile("^\\w+$");
Matcher m_passwordAgain = p_passwordAgain.matcher(passwordAgain);
boolean b_passwordAgain = m_passwordAgain.matches();
if(b_userName){
System.out.println("輸入的使用者名稱合法！");
label_user.setText("");
if(b_password){
System.out.println("輸入的密碼合法！");
label_password.setText("");
if(b_passwordAgain){
System.out.println("輸入的密碼合法！");
label_passwordAgain.setText("");
try {
//判斷該使用者是否存在
String select ="select count(*) from user where name= '"+userName+"'";
ResultSet set =statement.executeQuery(select);
set.first();
int num = set.getInt(1);
if(num>0){
System.out.println("該使用者已經存在！");
}else{
if(passwordAgain.equals(password))
{
String insert = "insert into user(name, password) values('"+userName+"','"+password+"')";
statement.execute(insert);
System.out.println("使用者註冊成功！");
textFieldUserName.setText("");
textFieldPassword.setText("");
textFieldPasswordAgain.setText("");
}
else{
System.out.println("輸入的兩次密碼不一致！，請重新輸入……");
}
}
} catch (SQLException e1) {
e1.printStackTrace();
}
}else{
String warning_passwordAgain = "輸入的密碼不合法！";
System.out.println(warning_passwordAgain);
label_passwordAgain.setText(warning_passwordAgain);
textFieldPasswordAgain.setText("");
}
}else{
String warning_password = "輸入的密碼不合法！";
label_password.setText(warning_password);
System.out.println(warning_password);
textFieldPassword.setText("");
}
}else{
String warning_user = "輸入的使用者名稱不合法！";
label_user.setText(warning_user);
System.out.println(warning_user);
textFieldUserName.setText("");
}
}
});
btnNewButton.setBounds(149, 248, 93, 23);
contentPane.add(btnNewButton);
label_user = new JLabel("");
label_user.setBounds(285, 80, 150, 15);
contentPane.add(label_user);
label_password = new JLabel("");
label_password.setBounds(289, 123, 150, 15);
contentPane.add(label_password);
label_passwordAgain = new JLabel("");
label_passwordAgain.setBounds(289, 178, 150, 15);
contentPane.add(label_passwordAgain);
}
private JLabel label_user;
private JLabel label_password ;
private JLabel label_passwordAgain;
}
登入
功能實現
資料庫中使用者和密碼的儲存：
登入介面：
登入程式碼
//SQLManager類
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
//採用單例設計模式
public class SQLManager {
private Connection connection;
private Statement statement;
//獲得statement
public Statement getStatement() {
return statement;
}
//賦值statement
public void setStatement(Statement statement) {
this.statement = statement;
}
//獲得Connection
public Connection getConnection() {
return connection;
}
//賦值Connection
public void setConnection(Connection connection) {
this.connection = connection;
}
private static SQLManager manager;
private SQLManager() {
//連線資料庫的驅動
String driver = "com.mysql.jdbc.Driver";
//指向資料庫訪問地址
String url = "jdbc:mysql://localhost:3306/clazz";
//資料庫的使用者名稱
String user = "root";
//資料庫使用者密碼
String password = "123456";
try {
//載入驅動
Class.forName(driver);
//與資料庫建立連線
connection = DriverManager.getConnection(url,user, password);
if(!connection.isClosed()){
//建立資料庫操作類
statement = connection.createStatement();
}else{
System.out.println("請開啟資料庫！");
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}
/**
* 建立該類的物件
* @return 返回SQLManager物件。
*/
public static synchronized SQLManager newInstance(){
if(manager==null){
manager = new SQLManager();
}
return manager;
}
}//登入
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.awt.event.ActionEvent;
public class Login extends JFrame {
private JPanel contentPane;
private JTextField textUserName;
private JTextField textPassword;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
Login frame = new Login();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public Login() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 451, 410);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
JLabel lblLogin = new JLabel("登入介面");
lblLogin.setBounds(167, 57, 70, 31);
contentPane.add(lblLogin);
textUserName = new JTextField();
textUserName.setBounds(153, 115, 137, 21);
contentPane.add(textUserName);
textUserName.setColumns(10);
textPassword = new JTextField();
textPassword.setBounds(153, 168, 137, 21);
contentPane.add(textPassword);
textPassword.setColumns(10);
JButton btnNewButton = new JButton("登入");
btnNewButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String userName = textUserName.getText();
String password = textPassword.getText();
Connection conn = SQLManager.newInstance().getConnection();
String sql = "select * from user where name= ? and password=? ";
try {
PreparedStatement statement = conn.prepareStatement(sql);
statement.setString(1, userName);
statement.setString(2, password);
ResultSet set = statement.executeQuery();
set.last();//移動到最後一行。
int num = set.getRow();
if(num>0){
System.out.println(num);
System.out.println("使用者登入成功！");
textUserName.setText("");
textPassword.setText("");
}else{
System.out.println(num);
System.out.println("使用者登入失敗！");
textUserName.setText("");
textPassword.setText("");
}
} catch (SQLException e1) {
e1.printStackTrace();
}
}
});
btnNewButton.setBounds(170, 246, 93, 23);
contentPane.add(btnNewButton);
JLabel lblUser = new JLabel("使用者名稱：");
lblUser.setBounds(55, 118, 54, 15);
contentPane.add(lblUser);
JLabel lblPassword = new JLabel("密碼：");
lblPassword.setBounds(55, 171, 54, 15);
contentPane.add(lblPassword);
}
}