我不断收到没有这样的表的错误：employeeInfo。该表存在于我用于代码的目录中。顺便说一下，我在Mac上。这是代码：
import java.sql.*;
import javax.swing.*;
public class javaconnect {
Connection conn = null;
public static Connection ConnecrDb(){
try{
Class.forName("org.sqlite.JDBC");
Connection conn = DriverManager.getConnection("jdbc:sqlite:Macintosh HD\\Users\\as\\Documents\\Netbeans projects\\Project123.sqlite");
JOptionPane.showMessageDialog(null, "Connection Established");
return conn;
}
catch(Exception ex){
JOptionPane.showMessageDialog(null,ex);
return null;
}
}
public static void main(String args[]){
ConnecrDb();
}
我觉得错误就在这一行： Connection conn = DriverManager.getConnection（“jdbc：sqlite：Macintosh HD \ Users \ as \ Documents \ Netbeans projects \ Project123.sqlite”）;
employeeInfo表确实存在于此数据库中，这也是当前目录。 这是我的代码的第二部分：
import java.awt.*;
import java.sql.*;
import javax.swing.*;
public class Login_jframe extends javax.swing.JFrame {
Connection conn = null;
ResultSet rs = null;
PreparedStatement pst = null;
/**
* Creates new form Login_jframe
*/
public Login_jframe() {
initComponents();
conn = javaconnect.ConnecrDb();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jPanel1 = new javax.swing.JPanel();
txt_password = new javax.swing.JPasswordField();
jLabel2 = new javax.swing.JLabel();
txt_username = new javax.swing.JTextField();
jLabel1 = new javax.swing.JLabel();
cmd_login = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jPanel1.setBorder(javax.swing.BorderFactory.createTitledBorder(null, "Login", javax.swing.border.TitledBorder.DEFAULT_JUSTIFICATION, javax.swing.border.TitledBorder.DEFAULT_POSITION, new java.awt.Font("Lucida Grande", 1, 18), new java.awt.Color(102, 102, 255))); // NOI18N
txt_password.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
txt_passwordActionPerformed(evt);
}
});
jLabel2.setText("Password");
jLabel1.setText("Username");
cmd_login.setText("Login");
cmd_login.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
cmd_loginActionPerformed(evt);
}
});
javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
jPanel1.setLayout(jPanel1Layout);
jPanel1Layout.setHorizontalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel1Layout.createSequentialGroup()
.addContainerGap()
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel1Layout.createSequentialGroup()
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jLabel1)
.addComponent(jLabel2))
.addGap(18, 18, 18)
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
.addComponent(txt_username, javax.swing.GroupLayout.PREFERRED_SIZE, 167, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(txt_password, javax.swing.GroupLayout.PREFERRED_SIZE, 167, javax.swing.GroupLayout.PREFERRED_SIZE))
.addContainerGap())
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel1Layout.createSequentialGroup()
.addComponent(cmd_login)
.addGap(67, 67, 67))))
);
jPanel1Layout.setVerticalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel1Layout.createSequentialGroup()
.addContainerGap()
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel1)
.addComponent(txt_username, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(64, 64, 64)
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel2)
.addComponent(txt_password, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(18, 18, 18)
.addComponent(cmd_login)
.addContainerGap(12, Short.MAX_VALUE))
);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addContainerGap(218, Short.MAX_VALUE)
.addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(40, 40, 40))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(57, 57, 57)
.addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(28, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void txt_passwordActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
private void cmd_loginActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
String sql = "select * from employeeInfo where username=? and password=?";
try{
pst = conn.prepareStatement(sql);
pst.setString(1, txt_username.getText());
pst.setString(2,txt_password.getText());
rs = pst.executeQuery();
if(rs.next()){
JOptionPane.showMessageDialog(null,"Username and Password is correct");
Employee_info s = new Employee_info();
s.setVisible(true);
}
else{
JOptionPane.showMessageDialog(null,"Username and/or Password is not correct");
}
}
catch(Exception ex){
JOptionPane.showMessageDialog(null, ex);
}
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(Login_jframe.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(Login_jframe.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(Login_jframe.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(Login_jframe.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new Login_jframe().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton cmd_login;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel2;
private javax.swing.JPanel jPanel1;
private javax.swing.JPasswordField txt_password;
private javax.swing.JTextField txt_username;
// End of variables declaration
}
答案 0 :(得分：0)
没关系，我把它弄清楚了。显然，我必须单击Database，选择Connect Database，然后浏览到我保存数据库的位置。在我正在观看的教程视频中从未提及过这一点。希望这个答案有助于遇到同样问题的其他人。