Am I using try with resources correctly or what is the problem here?

Question

Java

After validation, the request comes here but does not enter the Connection block, who can tell what is the problem?
I don't get any errors about the connection problem, I don't know what to look for .. Any advice would be appreciated!!!

public class LoginService {

    private static ConnectionPool connectionPool = ConnectionPool.con_instance;
    private static Connection con = null;

    public static boolean checkUser(TreeMap<String, String> sortedData, HttpServletResponse response) throws CouponSystemException {

        String name = sortedData.get("nickname");
        String password = sortedData.get("password");
        String email = sortedData.get("email");

        System.out.println(name + ": " + password + ": " + email + " Login service"); // Печатает! После чего заходит в finally и всё!

        try (Connection con = connectionPool.getConnection()){ //  В сам блок как будто не заходит. 

            System.out.println("Before Pre"); // No input
                String queryDataBase = "SELECT nick_name,password,email FROM users  WHERE nick_name = ? AND password = ? AND email = ?";

                PreparedStatement preparedStatement = con.prepareStatement(queryDataBase);
                preparedStatement.setString(1, sortedData.get("nickname"));
                preparedStatement.setString(2, sortedData.get("password"));
                preparedStatement.setString(3, sortedData.get("email"));
                ResultSet resultSetQuery = preparedStatement.executeQuery();
            System.out.println("After Pre"); // No input
                while (resultSetQuery.next()) {
                    if (resultSetQuery.getString("nick_name").equals(sortedData.get("nickname"))) {
                        if (resultSetQuery.getString("password").equals(sortedData.get("password"))) {
                            if (resultSetQuery.getString("email").equals(sortedData.get("email"))) {

                                try {
                                    ResponseDataHandler.ToJsonResponse("success", response);
                                    System.out.println("Success");
                                } catch (IOException io) {
                                    throw new CouponSystemException(io.getMessage());
                                }

                                return true;
                            }
                        }
                    } else if (resultSetQuery.getString("nick_name").equals(null)) {
                        return false;
                    }
                }
                   return false;

        } catch (SQLException e) {
            throw new CouponSystemException(e.getMessage());
        }finally {
            connectionPool.returnConnection(con); // Это строка работает!
        }
    }
}

Tomcat folder:

Jariki that I deploy.

Answer 1

It may not enter if Connection con = connectionPool.getConnection() throws an exception.
Try to debug and/or add some System.out.println("Inside catch block!");