利用JDBC数据库技术，参考API文档，编写一个简单的登陆程序。程序运行的界面如下图所示：要求：

发布网友 发布时间：2022-05-02 03:40

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热心网友 时间：2022-05-02 05:09

数据库你自己建吧，这个很容易的。我数据库是房子C盘根目录的，叫stu.mdb（用2003建的）。你要是用2007建的，可以打开另存为2000-2003格式的就可以了。sql和数据库位置可以在代码里改。
代码：
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.GroupLayout;
import javax.swing.GroupLayout.Alignment;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPasswordField;
import javax.swing.JTextField;

public class TestGra extends JFrame {

private Connection conn;

public TestGra() {
init();
pack();
setLocationRelativeTo(null);
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}

private void init() {
JLabel lblUserName = new JLabel("用户名");
final JTextField txtUserName = new JTextField();

JLabel lblPassword = new JLabel("密码");
final JPasswordField pwfPassword = new JPasswordField();

JButton btnLogin = new JButton("登陆");
btnLogin.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
getConnect();
if (conn == null) {
JOptionPane.showMessageDialog(null, "数据库链接失败");
return;
}

boolean isOK = checkUser(txtUserName.getText().trim(),
new String(pwfPassword.getPassword()));
if (isOK) {
JOptionPane.showMessageDialog(null, "登陆成功");
} else {
JOptionPane.showMessageDialog(null, "用户名或密码不正确");
}
closeConnect();
}
});
JButton btnCancel = new JButton("退出");
btnCancel.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.exit(0);
}
});

GroupLayout layout = new GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setAutoCreateGaps(true);
layout.setAutoCreateContainerGaps(true);

GroupLayout.SequentialGroup hGroup = layout.createSequentialGroup();
hGroup.addGroup(layout.createParallelGroup().addComponent(lblUserName)
.addComponent(lblPassword));
hGroup.addGroup(layout
.createParallelGroup()
.addComponent(txtUserName, GroupLayout.PREFERRED_SIZE, 180,
GroupLayout.PREFERRED_SIZE)
.addComponent(pwfPassword, GroupLayout.PREFERRED_SIZE, 180,
GroupLayout.PREFERRED_SIZE)
.addGroup(
Alignment.CENTER,
layout.createSequentialGroup().addComponent(btnLogin)
.addComponent(btnCancel)));
layout.setHorizontalGroup(hGroup);

GroupLayout.SequentialGroup vGroup = layout.createSequentialGroup();
vGroup.addGap(15);
vGroup.addGroup(layout
.createParallelGroup(GroupLayout.Alignment.CENTER)
.addComponent(lblUserName)
.addComponent(txtUserName, GroupLayout.PREFERRED_SIZE, 25,
GroupLayout.PREFERRED_SIZE));
vGroup.addGroup(layout
.createParallelGroup(GroupLayout.Alignment.CENTER)
.addComponent(lblPassword)
.addComponent(pwfPassword, GroupLayout.PREFERRED_SIZE, 25,
GroupLayout.PREFERRED_SIZE));
vGroup.addGroup(layout
.createParallelGroup(GroupLayout.Alignment.CENTER)
.addComponent(btnLogin).addComponent(btnCancel));
layout.setVerticalGroup(vGroup);
}

/**
* 打开连接
*/
private void getConnect() {

if (conn != null) {
return;
}

try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
conn = DriverManager.getConnection("jdbc:odbc:Driver={MicroSoft Access Driver (*.mdb)};DBQ=c:/stu.mdb", "", "");
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}

private boolean checkUser(String name, String pwss) {
String userName = "";
Statement stmt = null;
try {
stmt = conn.createStatement();

ResultSet rs = stmt.executeQuery(
"SELECT username FROM userinfo WHERE username = '" + name + "' AND password = '" + pwss +"'");
if (rs.next()) {
userName = rs.getString(1).trim();
}
stmt.close();

if (userName.equals("")) {
return false;
} else {
return true;
}
} catch (SQLException e) {
e.printStackTrace();
}

return false;
}

/**
* 关闭链接
*/
private void closeConnect() {
try {
conn.close();
conn = null;
} catch (SQLException e) {
e.printStackTrace();
}
}

/**
* @param args
*/
public static void main(String[] args) {
new TestGra().setVisible(true);
}
}