Overriding LemonService methods

If you remember, in the last section we created a MyService like this:

@Service
public class MyService extends LemonService<User, Long> {

    @Override
    protected User newUser() {
        return new User();
    }

    @Override
    public Long parseId(String id) {
        return Long.valueOf(id);
    }
}

To complete giving a name to our users, we now need to override a few super methods.

Signing up

For signing up, we don't need to code anything here. Adding groups = {SignUpValidation.class... in the User entity was enough.

Updating the user profile

For updating the user profile, override updateUserFields as below:

@Override
protected void updateUserFields(User user, User updatedUser, User currentUser) {

    super.updateUserFields(user, updatedUser, currentUser);

    user.setName(updatedUser.getName());

    LemonUtils.afterCommit(() -> {
        if (currentUser.equals(user))
            currentUser.setName(user.getName());
    });
}

As you see, the super method would be called first. Then, the name would be updated. Finally, if a user is updating his own profile, Spring Security's principal would also be updated.

The documentation and resources cover it in details. Another good way to get more familiar with Spring Lemon is to browse its source code. For example, if you are using STS, pressing F3 while your mouse is over super.updateUserFields(...) will show you its source code.

Creating the admin user

If you remember, we told you that an ADMIN user is added at application startup if it doesn't already exist. Override the createAdminUser method to give it a name:

@Override
protected User createAdminUser() {

    User user = super.createAdminUser(); 
    user.setName("Administrator");
    return user;
}

Note: If you are using a persistent database and tried running the application in the last section, the ADMIN user would already have been created in your local database. Unless you delete that user from the database, the above code wouldn't be run by Spring Lemon, and so the name of the ADMIN user would not be set.

Including current user's name in the response

When asked by a client, Spring Lemon provides some information about the currently logged in user. To include name in that, override userForClient:

@Override
protected User userForClient(User currentUser) {

    User user = super.userForClient(currentUser);
    if (user != null)
        user.setName(currentUser.getName());
    return user;
}

Your application is complete!

This completes your application! Here is the documentation of the API that you have just developed. This API can be used from single page JavaScript applications or any consumer. In fact, we have created a Demo Angular 1.x front-end application, which you can use to test your API out.

Note: Check our Lemon Demo Application, which is quite similar to the one you just developed, but additionally has automated tests.