I have a design issue that I don't know how to solve. I'm using Spring 3.2.4 and Spring security 3.1.4.

I have a Account table in my database that looks like this:

create table Account (id identity,
                        username varchar unique,
                        password varchar not null,
                        firstName varchar not null, 
                        lastName varchar not null,
                        university varchar not null,
                        primary key (id));

Until recently my username was just only a username but I changed it to be the email address instead since many users want to login with that instead.

I have a header that I include on all my pages which got a link to the users profile like this:

<a href="/project/users/<%= request.getUserPrincipal().getName()%>" class="navbar-link"><strong><%= request.getUserPrincipal().getName()%></strong></a>

The problem is that <%= request.getUserPrincipal().getName()%> returns the email now, I don't want to link the user's with thier emails. Instead I want to use the id every user have to link to the profile.

How do I reach the users id's from every page?

I have been thinking of two solutions but I'm not sure:

1. Change the principal to contain the id as well, don't know how to do this and having problem finding good information on the topic.
2. Add a model attribute to all my controllers that contain the whole user but this would be really ugly, like this.

Account account = entityManager.find(Account.class, email);
model.addAttribute("account", account);

There are more way's as well and I have no clue which one is to prefer.

I hope it's clear enough and thank you for any help on this.

====== Edit according to answer =======

I edited Account to implement UserDetails, it now looks like this (will fix the auto generated stuff later):

@Entity
@Table(name="Account")
public class Account implements UserDetails {

    @Id
    private int id;

    private String username;

    private String password;

    private String firstName;

    private String lastName;

    @ManyToOne
    private University university;

    public Account() {

    }

    public Account(String username, String password, String firstName, String lastName, University university) {
        this.username = username;
        this.password = password;
        this.firstName = firstName;
        this.lastName = lastName;
        this.university = university;
    }

    public String getUsername() {
        return username;
    }

    public String getPassword() {
        return password;
    }

    public String getFirstName() {
        return firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public University getUniversity() {
        return university;
    }

    public void setUniversity(University university) {
        this.university = university;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    @Override
    public Collection<? extends GrantedAuthority> getAuthorities() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public boolean isAccountNonExpired() {
        // TODO Auto-generated method stub
        return false;
    }

    @Override
    public boolean isAccountNonLocked() {
        // TODO Auto-generated method stub
        return false;
    }

    @Override
    public boolean isCredentialsNonExpired() {
        // TODO Auto-generated method stub
        return false;
    }

    @Override
    public boolean isEnabled() {
        // TODO Auto-generated method stub
        return true;
    }
}

I also added

<%@ taglib prefix="sec" uri="http://www.springframework.org/security/tags" %>

To my jsp files and trying to reach the id by

<sec:authentication property="principal.id" />

This gives me the following

org.springframework.beans.NotReadablePropertyException: Invalid property 'principal.id' of bean class [org.springframework.security.authentication.UsernamePasswordAuthenticationToken]: Bean property 'principal.id' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?

====== Edit 2 according to answer =======

I based my application on spring social samples and I never had to change anything until now.

This are the files I think are relevant, please tell me if theres something you need to see besides this.

AccountRepository.java

public interface AccountRepository {

    void createAccount(Account account) throws UsernameAlreadyInUseException;

    Account findAccountByUsername(String username);

}

JdbcAccountRepository.java

@Repository
public class JdbcAccountRepository implements AccountRepository {

    private final JdbcTemplate jdbcTemplate;

    private final PasswordEncoder passwordEncoder;

    @Inject
    public JdbcAccountRepository(JdbcTemplate jdbcTemplate, PasswordEncoder passwordEncoder) {
        this.jdbcTemplate = jdbcTemplate;
        this.passwordEncoder = passwordEncoder;
    }

    @Transactional
    public void createAccount(Account user) throws UsernameAlreadyInUseException {
        try {
            jdbcTemplate.update(
                    "insert into Account (firstName, lastName, username, university, password) values (?, ?, ?, ?, ?)",
                    user.getFirstName(), user.getLastName(), user.getUsername(), user.getUniversity(),
                    passwordEncoder.encode(user.getPassword()));
        } catch (DuplicateKeyException e) {
            throw new UsernameAlreadyInUseException(user.getUsername());
        }
    }

    public Account findAccountByUsername(String username) {
        return jdbcTemplate.queryForObject("select username, firstName, lastName, university from Account where username = ?",
                new RowMapper<Account>() {
                    public Account mapRow(ResultSet rs, int rowNum) throws SQLException {
                        return new Account(rs.getString("username"), null, rs.getString("firstName"), rs.getString("lastName"), new University("test"));
                    }
                }, username);
    }

}

security.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns="http://www.springframework.org/schema/security"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:beans="http://www.springframework.org/schema/beans"
    xsi:schemaLocation="http://www.springframework.org/schema/security http://www.springframework.org/schema/security/spring-security-3.1.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd">

    <http pattern="/resources/**" security="none" />
    <http pattern="/project/" security="none" />

    <http use-expressions="true">
        <!-- Authentication policy -->
        <form-login login-page="/signin" login-processing-url="/signin/authenticate" authentication-failure-url="/signin?error=bad_credentials" />
        <logout logout-url="/signout" delete-cookies="JSESSIONID" />
        <intercept-url pattern="/addcourse" access="isAuthenticated()" />
        <intercept-url pattern="/courses/**/**/edit" access="isAuthenticated()" />
        <intercept-url pattern="/users/**/edit" access="isAuthenticated()" />
    </http>

    <authentication-manager alias="authenticationManager">
        <authentication-provider>
            <password-encoder ref="passwordEncoder" />
            <jdbc-user-service data-source-ref="dataSource" 
                            users-by-username-query="select username, password, true from Account where username = ?"
                            authorities-by-username-query="select username, 'ROLE_USER' from Account where username = ?"/>
        </authentication-provider>
        <authentication-provider>
            <user-service>
                <user name="admin" password="admin" authorities="ROLE_USER, ROLE_ADMIN" />
            </user-service>
        </authentication-provider>
    </authentication-manager>

</beans:beans>

And this is my try of implementing a UserDetailsService

public class RepositoryUserDetailsService implements UserDetailsService {

    private final AccountRepository accountRepository;

    @Autowired
    public RepositoryUserDetailsService(AccountRepository repository) {
        this.accountRepository = repository;
    }

    @Override
    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
        Account user = accountRepository.findAccountByUsername(username);

        if (user == null) {
            throw new UsernameNotFoundException("No user found with username: " + username);
        }

        return user;

    }
}

Still gives me the same error, do I need to add the UserDetailsService somewhere? This is starting to be something else compared to my initial question, I should maybe start another question.

Sorry for my lack of experience in this. I have to read up.