Successful login response with a 404 - spring-security

Question

Currently, I learning security and I'm trying to make a simple login for my Android app. I'm using a custom Filter to request access to my protected data. This way I don't need the default login-page, and use a custom login in my android app instead. But when I do a successful login, I get a 404 response instead of a 200. I there a way to change this as it is set up right now?
MAIN.class
package com.ssl.Oauth2;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
#SpringBootApplication
public class Main {
public static void main(String[] args) {
SpringApplication.run(Main.class, args);
}
}
Controller.class
#RestController
public class Controller {
#RequestMapping("/protected-resource")
public String protectedResource() {
return "The Protected Resource";
}
#RequestMapping("/public-resource")
public String publicResource() {
return "The Public Resource";
}
}
SecurityConfiguration.class
import org.springframework.http.HttpMethod;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
#EnableWebSecurity
public class SecurityConfiguration extends WebSecurityConfigurerAdapter {
#Override
protected void configure(AuthenticationManagerBuilder auth) throws Exception {
auth.inMemoryAuthentication().withUser("john").password("{noop}12345").roles("USER");
}
#Override
protected void configure(HttpSecurity http) throws Exception {
CustomFilter mupaf = new CustomFilter();
mupaf.setAuthenticationManager(authenticationManager());
http
.csrf().disable()
.addFilterAt(
mupaf,
UsernamePasswordAuthenticationFilter.class)
.authorizeRequests()
.antMatchers(HttpMethod.GET, "/protected-resource").authenticated()
.antMatchers(HttpMethod.POST, "/login").permitAll();
}
}
CustomFilter
package com.ssl.Oauth2;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.security.authentication.AuthenticationServiceException;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.AuthenticationException;
import org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter;
import org.springframework.security.web.util.matcher.AntPathRequestMatcher;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Map;
public class CustomFilter extends AbstractAuthenticationProcessingFilter {
protected CustomFilter() {
super(new AntPathRequestMatcher("/login", "POST"));
//
}
#Override
public Authentication attemptAuthentication(
HttpServletRequest request, HttpServletResponse response) throws AuthenticationException {
String username, password;
// Credentials to Java Map
try {
Map<String, String> requestMap = new ObjectMapper().readValue(request.getInputStream(), Map.class);
username = requestMap.get("username");
password = requestMap.get("password");
} catch (IOException e) {
throw new AuthenticationServiceException(e.getMessage(), e);
}
// Token
UsernamePasswordAuthenticationToken authRequest = new UsernamePasswordAuthenticationToken(
username, password);
// TEST
System.out.println("\n------------------------------------------------\n");
System.out.println("AUTHENTICATION REQUEST:\n" +this.getAuthenticationManager().authenticate(authRequest) );
System.out.println("\n------------------------------------------------\n");
// the method authenticate of the AuthenticationManager receives a token
return this.getAuthenticationManager().authenticate(authRequest);
}
}