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JAVA MYsql login form - login function does not work properly ( Javafx)

here is my code for the method that I created for my login form.
Everytime "login failed " message commes up even if I entered correct username and password.
What can be wrong here.
public class Controller {
#FXML
private Button cancelbutton;
#FXML
private Label loginmessagelabel;
#FXML
private PasswordField password1;
#FXML
private TextField username1;
PreparedStatement pst;
ResultSet rs;
public void validatelogin() throws SQLException, ClassNotFoundException {
String jdbcURL = "jdbc:mysql://localhost/medibase";
String username = "root";
String password = "0852";
Connection connection = DriverManager.getConnection(jdbcURL,username,password);
Class.forName("com.mysql.jdbc.Driver");
pst=connection.prepareStatement("SELECT * FROM user_account WHERE username=? and password=?");
pst.setString(1, String.valueOf(username1));
pst.setString(2, String.valueOf(password1));
rs = pst.executeQuery();
if(rs.next()){
loginmessagelabel.setText("Congratulations");
} else{
loginmessagelabel.setText("Login failed");
}
}

I found the mistake and fixed it
here are the changes that I made.
String uname = username1.getText();
String psd = password1.getText();
pst=connection.prepareStatement("SELECT * FROM user_account WHERE
username=? and password=?");
pst.setString(1, uname);
pst.setString(2, psd);
I took separate variables and assigned the vales form the textboxes by useing getText() method.

Connection reset when unable to write into MySQL

I have this method here - whenever I comment out the MySQL section, from String query to pst.close() - the code works fine. However, if I don't, then it gives me the error of Connection Reset. I am using a socket between a client and a server for your information. How would I fix this? Or it it a problem that does not deal with MySQL?
public static String doAddUser(String username, String password, String email, String fullname) throws SQLException {
String returnStatement = "";
Connection connection = establishConnection();
if(email.isEmpty() || password.isEmpty()) {
returnStatement = "CreateFailure: Some fields are left blank. Please note that all fields are required. Please try again";
}
else {
String query = "insert into test(`username`, `password`, `email`, `fullname`) values (?,?,?,?)";
PreparedStatement pst = connection.prepareStatement(query);
pst.setString(1, username);
pst.setString(2, password);
pst.setString(3, email);
pst.setString(4, fullname);
pst.executeUpdate();
pst.close();
returnStatement = "CreateSuccess: You are now registered!";
}
return returnStatement;
}

You should probably have a connection.close() before the return.
Or, if you are in a relatively new version of JRE, you could possibly achieve the same with try-with-resource.
public static String doAddUser(String username, String password, String email, String fullname) throws SQLException {
String returnStatement = "";
try (Connection connection = establishConnection()) {
if(email.isEmpty() || password.isEmpty()) {
returnStatement = "CreateFailure: Some fields are left blank. Please note that all fields are required. Please try again";
}
else {
String query = "insert into test(`username`, `password`, `email`, `fullname`) values (?,?,?,?)";
PreparedStatement pst = connection.prepareStatement(query);
pst.setString(1, username);
pst.setString(2, password);
pst.setString(3, email);
pst.setString(4, fullname);
pst.executeUpdate();
pst.close();
returnStatement = "CreateSuccess: You are now registered!";
}
}
return returnStatement;
}
This will ensure that your connection closes when the try block finishes. However, that would require that the Connection class implements the AutoCloseable interface.

I think the connection is getting established and not getting closed, might be the issue.

Here is what works for me, as suggested by #Binaek Sarkar (I modified it a little bit):
public static String doAddUser(String username, String password, String email, String fullname) throws SQLException {
String returnStatement = "";
try {
if(email.isEmpty() || password.isEmpty()) {
returnStatement = "CreateFailure: Some fields are left blank. Please note that all fields are required. Please try again";
}
else {
Connection connection = null;
connection = MySQLConnection.dbConnector();
String query = "INSERT INTO `test`(`username`, `password`, `email`, `fullname`) VALUES (?,?,?,?)";
PreparedStatement pst = connection.prepareStatement(query);
pst.setString(1, username);
pst.setString(2, password);
pst.setString(3, email);
pst.setString(4, fullname);
pst.executeUpdate();
pst.close();
returnStatement = "CreateSuccess: You are now registered! You will redirected to the login page now. ";
}
}catch(Exception e) {returnStatement = "Invalid. Please try again!";}
return returnStatement;
}

How to fix ORA-01008 : Not all variables bound

I have a problem with this piece of code. When I pass user and pass arguments to isLogin fucntion it throws ORA-01008 errror. I am connected to Oracle database using jdbc.
public boolean isLogin(Connection conn, String user, String pass) throws SQLException{
String sql = "SELECT * FROM PRACOWNIK WHERE imie =? AND nazwisko =? ";
PreparedStatement stmt;
ResultSet rs;
try {
stmt = conn.prepareStatement(sql);
stmt.setString(1, user);
stmt.setString(2, pass);
rs = stmt.executeQuery(sql);
if(rs.next()){
return true;
}
else {
return false;
}
} catch (SQLException e){
Alert alert = new Alert(Alert.AlertType.ERROR);
alert.setTitle("Error ");
alert.setContentText(e.getMessage());
alert.showAndWait();
return false;
}
}
I use this function in Controller class
public class Controller implements Initializable{
public Pracownik pracownik = new Pracownik();
#FXML
private Label isConnected;
#FXML
private TextField txtUsername;
#FXML
private TextField txtPass;
private Connection conn;
// private ObservableList<Pracownik> lista = FXCollections.observableArrayList();
public void initialize(URL url, ResourceBundle rb){
conn = DBConnection.getConnection();
// lista = new Pracownik().getAll(conn);
}
public void login(ActionEvent event){
try {
if(pracownik.isLogin(conn, txtUsername.getText(), txtPass.getText())){
isConnected.setText("Correct");
}
else{
isConnected.setText("False");
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}
And this is a error message
Caused by: Error : 1008, Position : 0, Sql = SELECT pesel FROM PRACOWNIK WHERE imie =:1 AND nazwisko =:2 , OriginalSql = SELECT pesel FROM PRACOWNIK WHERE imie =? AND nazwisko =? , Error Msg = ORA-01008: not all variables bound
When I use normal Select query just to print the table everything is fine.

You should NOT specify the SQL query again. It's already specified. Change the line:
rs = stmt.executeQuery(sql); // method from java.sql.Statement
to:
rs = stmt.executeQuery(); // method from java.sql.PreparedStatement
The first method does not take parameters into consideration and runs the SQL "as is"... and therefore you get the error you mention.

how to update mysql with textfield and jcombobox in java

private void UpdateActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
//Update
try{
if(!(jTextField1.getText().isEmpty())){
Connection myConn= null;
Statement myStmt= null;
ResultSet myRs= null;
String user= "root";
String pass= "passwd14";
//Get Connection to database
myConn = DriverManager.getConnection("jdbc:mysql://localhost:3306/company",user, pass);
//Create a Statement
myStmt = myConn.createStatement();
//Prepared Statement
PreparedStatement pst=null;
try{
String on= jTextField1.getText();
//Prepare statement Execution
String sql2 = "UPDATE amazon SET name =?, mob =?, oddt =? FROM amazon WHERE odn ='"+on+"'";
pst=myConn.prepareStatement(sql2);
//pst.setString(4,jTextField1.getText());
pst.setString(1,jTextField2.getText());
pst.setString(2,jTextField6.getText());
pst.setString(3,jTextField5.getText());
pst.executeUpdate();
//Update ComboBox
String s= (String)jComboBox1.getSelectedItem();
jComboBox1.setSelectedItem(s);
String s2= (String)jComboBox2.getSelectedItem();
jComboBox1.setSelectedItem(s2);
JOptionPane.showMessageDialog(this,"Record Saved..");
}catch (Exception e){
JOptionPane.showMessageDialog(this,"Error");
}
}
}catch (Exception ex){
JOptionPane.showMessageDialog(this," This Error.. Keeps Showing up");
}
}
This is the database I want to update :
amazon(name, mob, iss, stat, oddt, odn)
that is (name, mobile, issue, status, order_details, orderno)

Update Query
It will work
String sql2 = "UPDATE amazon SET name =?, mob =?, oddt =? WHERE odn ='"+on+"'";

Deleteing data from database based on a jcomboBox throws an error

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt)
{
Connection conn=DbCon.conDB();
//String Mname =jComboBox1.getSelectedItem().toString();
String sql="delete Name from nowshowingmovie where Name = '"+jComboBox1.getSelectedItem().toString()+"'";
try{
pst=conn.prepareStatement(sql);
// pst.executeQuery();
pst.executeUpdate(sql);
JOptionPane.showMessageDialog(null,"Movie Deleted Sucessfully");
}
catch(SQLException e)
{
JOptionPane.showMessageDialog(null, e);
}
}

2 issues:
In general the syntax for DELETE is
String sql = "delete from nowshowingmovie where Name = '"+jComboBox1.getSelectedItem().toString()+"'";
PreparedStatement doesn't use the SQL String, i.e. just use pst.executeUpdate()
Side note: Since you're already using a PreparedStatement you can use a placeholder to avoid SQL injection attacks rather than using String concatenation.
String sql = "delete from nowshowingmovie where Name = ?";
pst.setString(1, jComboBox1.getSelectedItem().toString());
pst.executeUpdate();