View difference between Paste ID: T6ChQyMe and 3N8CCHxX

 package startupdemo.controller;
 
 import java.sql.Connection;
 import java.sql.ResultSet;
 import java.sql.Statement;
 
 import javax.annotation.Resource;
 
 import java.util.concurrent.locks.ReentrantLock;
 
 import org.jboss.logging.Logger;
 import org.springframework.ui.Model;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.servlet.mvc.support.RedirectAttributes;
 
 import startupdemo.service.MysqlService;
 import startupdemo.service.UserService;
 
 
 @RestController
 @RequestMapping("/login")
 public class LoginController
 {
 	private static Logger LOG = Logger.getLogger(LoginController.class);
 
 	private static String REDIRECT_PREFIX = "redirect:";
 
 	@Resource(name = "userService")
 	private UserService userService;
 
 	@Resource(name = "mysqlService")
 	private MysqlService mysqlService;
 
 	private final ReentrantLock lock = new ReentrantLock();
 
 	private String firstname;
 
 	@RequestMapping(method = RequestMethod.GET)
 	public String getLoginPage()
 	{
 		return "login";
 	}
 
 	@RequestMapping(method = RequestMethod.POST)
 	public String loginUser(@RequestParam(value = "username", required = true) final String username,
 			@RequestParam(value = "password", required = true) final String password,
 			final Model model, final RedirectAttributes redirectAttributes)
 	{
 		final boolean loginsuccess = authenticateUser(username, password);
 		if (loginsuccess)
 		{
 			// SUD-14 add customer greeting
 			redirectAttributes.addFlashAttribute("message", "Welcome to startupdemo, " + firstname + "!");
 
 			LOG.info("Login successful. Redirecting user to main application.");
 			return REDIRECT_PREFIX + "/startupdemo";
 		}
 
 		LOG.info("Login failed.");
 		model.addAttribute("errorMessage", "Could not login user " + username + ". Invalid username or password.");
 		return "login";
 	}
 
 	private boolean authenticateUser(final String username, final String password)
 	{
 		boolean result = false;
 		try
 		{
 			lock.lock();
 			final Connection connection = mysqlService.openMysqlConnection();
 
 			final Statement s = connection.createStatement();
 			final String q = "SELECT * FROM users WHERE username = '" + username + "' AND password = '" + password + "'";
 			final ResultSet rs = s.executeQuery(q);
 			if (rs.next())
 			{
 				result = true;
 				userService.setCurrentUser(username);
 				firstname = rs.getString("firstname");
 			}
 			rs.close();
 			s.close();
 
 			mysqlService.closeMysqlConnection();
 
 			lock.unlock();
 		}
 		catch (final Exception e)
 		{
 			LOG.error("Error happened while authenticating user.");
 		}
 		return result;
 	}
 
 }