#1037 Improve architecture of registration methods (#236)

* #1037 Improve architecture of registration methods
- Introduce parameters classes for each registration method
- RegistrationMethod has constants with the required parameters class -> no longer need to have a RegistrationExecutorProvider class that needs to be injected everywhere, let AsyncRegister be the only one to worry about which class will perform the registration
- Fix inheritance of password registration types - previously two-factor auth registration inherited from password registration directly

* Create matcher which checks for equality via reflections
- Allow to perform equality check on objects with default equals() method

src/main/java/fr/xephi/authme/AuthMe.java

@@ -15,6 +15,7 @@ import fr.xephi.authme.initialization.OnStartupTasks;
 import fr.xephi.authme.initialization.SettingsProvider;
 import fr.xephi.authme.initialization.TaskCloser;
 import fr.xephi.authme.initialization.factory.FactoryDependencyHandler;
+import fr.xephi.authme.initialization.factory.SingletonStoreDependencyHandler;
 import fr.xephi.authme.listener.BlockListener;
 import fr.xephi.authme.listener.EntityListener;
 import fr.xephi.authme.listener.PlayerListener;
@@ -206,7 +207,7 @@ public class AuthMe extends JavaPlugin {
 
         // Create injector, provide elements from the Bukkit environment and register providers
         injector = new InjectorBuilder()
-            .addHandlers(new FactoryDependencyHandler())
+            .addHandlers(new FactoryDependencyHandler(), new SingletonStoreDependencyHandler())
             .addDefaultHandlers("fr.xephi.authme")
             .create();
         injector.register(AuthMe.class, this);

src/main/java/fr/xephi/authme/api/NewAPI.java

@@ -5,7 +5,8 @@ import fr.xephi.authme.data.auth.PlayerAuth;
 import fr.xephi.authme.data.auth.PlayerCache;
 import fr.xephi.authme.datasource.DataSource;
 import fr.xephi.authme.process.Management;
-import fr.xephi.authme.process.register.executors.RegistrationExecutorProvider;
+import fr.xephi.authme.process.register.executors.ApiPasswordRegisterParams;
+import fr.xephi.authme.process.register.executors.RegistrationMethod;
 import fr.xephi.authme.security.PasswordSecurity;
 import fr.xephi.authme.security.crypts.HashedPassword;
 import fr.xephi.authme.service.PluginHookService;
@@ -35,15 +36,13 @@ public class NewAPI {
     private final Management management;
     private final ValidationService validationService;
     private final PlayerCache playerCache;
-    private final RegistrationExecutorProvider registrationExecutorProvider;
 
     /*
      * Constructor for NewAPI.
      */
     @Inject
     NewAPI(AuthMe plugin, PluginHookService pluginHookService, DataSource dataSource, PasswordSecurity passwordSecurity,
-           Management management, ValidationService validationService, PlayerCache playerCache,
+           Management management, ValidationService validationService, PlayerCache playerCache) {
-           RegistrationExecutorProvider registrationExecutorProvider) {
         this.plugin = plugin;
         this.pluginHookService = pluginHookService;
         this.dataSource = dataSource;
@@ -51,7 +50,6 @@ public class NewAPI {
         this.management = management;
         this.validationService = validationService;
         this.playerCache = playerCache;
-        this.registrationExecutorProvider = registrationExecutorProvider;
         NewAPI.singleton = this;
     }
 
@@ -204,8 +202,8 @@ public class NewAPI {
      * @param autoLogin Should the player be authenticated automatically after the registration?
      */
     public void forceRegister(Player player, String password, boolean autoLogin) {
-        management.performRegister(player,
+        management.performRegister(RegistrationMethod.API_REGISTRATION,
-            registrationExecutorProvider.getPasswordRegisterExecutor(player, password, autoLogin));
+            ApiPasswordRegisterParams.of(player, password, autoLogin));
     }
 
     /**

src/main/java/fr/xephi/authme/command/executable/register/RegisterCommand.java

@@ -7,7 +7,10 @@ import fr.xephi.authme.message.MessageKey;
 import fr.xephi.authme.process.Management;
 import fr.xephi.authme.process.register.RegisterSecondaryArgument;
 import fr.xephi.authme.process.register.RegistrationType;
-import fr.xephi.authme.process.register.executors.RegistrationExecutorProvider;
+import fr.xephi.authme.process.register.executors.EmailRegisterParams;
+import fr.xephi.authme.process.register.executors.PasswordRegisterParams;
+import fr.xephi.authme.process.register.executors.RegistrationMethod;
+import fr.xephi.authme.process.register.executors.TwoFactorRegisterParams;
 import fr.xephi.authme.security.HashAlgorithm;
 import fr.xephi.authme.service.CommonService;
 import fr.xephi.authme.service.ValidationService;
@@ -42,15 +45,12 @@ public class RegisterCommand extends PlayerCommand {
     @Inject
     private ValidationService validationService;
 
-    @Inject
-    private RegistrationExecutorProvider registrationExecutorProvider;
-
     @Override
     public void runCommand(Player player, List<String> arguments) {
         if (commonService.getProperty(SecuritySettings.PASSWORD_HASH) == HashAlgorithm.TWO_FACTOR) {
             //for two factor auth we don't need to check the usage
-            management.performRegister(player,
+            management.performRegister(RegistrationMethod.TWO_FACTOR_REGISTRATION,
-                registrationExecutorProvider.getTwoFactorRegisterExecutor(player));
+                TwoFactorRegisterParams.of(player));
             return;
         } else if (arguments.size() < 1) {
             commonService.send(player, MessageKey.USAGE_REGISTER);
@@ -82,8 +82,8 @@ public class RegisterCommand extends PlayerCommand {
             final String password = arguments.get(0);
             final String email = getEmailIfAvailable(arguments);
 
-            management.performRegister(
+            management.performRegister(RegistrationMethod.PASSWORD_REGISTRATION,
-                player, registrationExecutorProvider.getPasswordRegisterExecutor(player, password, email));
+                PasswordRegisterParams.of(player, password, email));
         }
     }
 
@@ -138,7 +138,8 @@ public class RegisterCommand extends PlayerCommand {
         if (!validationService.validateEmail(email)) {
             commonService.send(player, MessageKey.INVALID_EMAIL);
         } else if (isSecondArgValidForEmailRegistration(player, arguments)) {
-            management.performRegister(player, registrationExecutorProvider.getEmailRegisterExecutor(player, email));
+            management.performRegister(RegistrationMethod.EMAIL_REGISTRATION,
+                EmailRegisterParams.of(player, email));
         }
     }
 

src/main/java/fr/xephi/authme/initialization/factory/FactoryDependencyHandler.java

@@ -16,8 +16,8 @@ public class FactoryDependencyHandler implements DependencyHandler {
         if (dependencyDescription.getType() == Factory.class) {
             Class<?> genericType = ReflectionUtils.getGenericType(dependencyDescription.getGenericType());
             if (genericType == null) {
-                throw new IllegalStateException("Factory fields must have concrete generic type. " +
+                throw new IllegalStateException("Factory fields must have concrete generic type. "
-                    "Cannot get generic type for field in '" + context.getMappedClass() + "'");
+                    + "Cannot get generic type for field in '" + context.getMappedClass() + "'");
             }
 
             return new FactoryImpl<>(genericType, context.getInjector());

src/main/java/fr/xephi/authme/initialization/factory/SingletonStore.java

@@ -0,0 +1,37 @@
+package fr.xephi.authme.initialization.factory;
+
+import java.util.Collection;
+
+/**
+ * Injectable object to retrieve and create singletons of a common parent.
+ *
+ * @param <P> the parent class to which this store is limited to
+ */
+public interface SingletonStore<P> {
+
+    /**
+     * Returns the singleton of the given type, creating it if it hasn't been yet created.
+     *
+     * @param clazz the class to get the singleton for
+     * @param <C> type of the singleton
+     * @return the singleton of type {@code C}
+     */
+    <C extends P> C getSingleton(Class<C> clazz);
+
+    /**
+     * Returns all existing singletons of this store's type.
+     *
+     * @return all registered singletons of type {@code P}
+     */
+    Collection<P> retrieveAllOfType();
+
+    /**
+     * Returns all existing singletons of the given type.
+     *
+     * @param clazz the type to get singletons for
+     * @param <C> class type
+     * @return all registered singletons of type {@code C}
+     */
+    <C extends P> Collection<C> retrieveAllOfType(Class<C> clazz);
+
+}

src/main/java/fr/xephi/authme/initialization/factory/SingletonStoreDependencyHandler.java

@@ -0,0 +1,61 @@
+package fr.xephi.authme.initialization.factory;
+
+import ch.jalu.injector.Injector;
+import ch.jalu.injector.context.ResolvedInstantiationContext;
+import ch.jalu.injector.handlers.dependency.DependencyHandler;
+import ch.jalu.injector.handlers.instantiation.DependencyDescription;
+import ch.jalu.injector.utils.ReflectionUtils;
+
+import java.util.Collection;
+
+/**
+ * Dependency handler that builds {@link SingletonStore} objects.
+ */
+public class SingletonStoreDependencyHandler implements DependencyHandler {
+
+    @Override
+    public Object resolveValue(ResolvedInstantiationContext<?> context, DependencyDescription dependencyDescription) {
+        if (dependencyDescription.getType() == SingletonStore.class) {
+            Class<?> genericType = ReflectionUtils.getGenericType(dependencyDescription.getGenericType());
+            if (genericType == null) {
+                throw new IllegalStateException("Singleton store fields must have concrete generic type. "
+                    + "Cannot get generic type for field in '" + context.getMappedClass() + "'");
+            }
+
+            return new SingletonStoreImpl<>(genericType, context.getInjector());
+        }
+        return null;
+    }
+
+    private static final class SingletonStoreImpl<P> implements SingletonStore<P> {
+
+        private final Injector injector;
+        private final Class<P> parentClass;
+
+        SingletonStoreImpl(Class<P> parentClass, Injector injector) {
+            this.parentClass = parentClass;
+            this.injector = injector;
+        }
+
+        @Override
+        public <C extends P> C getSingleton(Class<C> clazz) {
+            if (parentClass.isAssignableFrom(clazz)) {
+                return injector.getSingleton(clazz);
+            }
+            throw new IllegalArgumentException(clazz + " not child of " + parentClass);
+        }
+
+        @Override
+        public Collection<P> retrieveAllOfType() {
+            return retrieveAllOfType(parentClass);
+        }
+
+        @Override
+        public <C extends P> Collection<C> retrieveAllOfType(Class<C> clazz) {
+            if (parentClass.isAssignableFrom(clazz)) {
+                return injector.retrieveAllOfType(clazz);
+            }
+            throw new IllegalArgumentException(clazz + " not child of " + parentClass);
+        }
+    }
+}

src/main/java/fr/xephi/authme/process/Management.java

@@ -8,7 +8,8 @@ import fr.xephi.authme.process.login.AsynchronousLogin;
 import fr.xephi.authme.process.logout.AsynchronousLogout;
 import fr.xephi.authme.process.quit.AsynchronousQuit;
 import fr.xephi.authme.process.register.AsyncRegister;
-import fr.xephi.authme.process.register.executors.RegistrationExecutor;
+import fr.xephi.authme.process.register.executors.RegistrationMethod;
+import fr.xephi.authme.process.register.executors.RegistrationParameters;
 import fr.xephi.authme.process.unregister.AsynchronousUnregister;
 import fr.xephi.authme.service.BukkitService;
 import org.bukkit.command.CommandSender;
@@ -60,8 +61,8 @@ public class Management {
         runTask(() -> asynchronousLogout.logout(player));
     }
 
-    public void performRegister(Player player, RegistrationExecutor registrationExecutor) {
+    public <P extends RegistrationParameters> void performRegister(RegistrationMethod<P> variant, P parameters) {
-        runTask(() -> asyncRegister.register(player, registrationExecutor));
+        runTask(() -> asyncRegister.register(variant, parameters));
     }
 
     public void performUnregister(Player player, String password) {

src/main/java/fr/xephi/authme/process/register/AsyncRegister.java

@@ -3,10 +3,13 @@ package fr.xephi.authme.process.register;
 import fr.xephi.authme.data.auth.PlayerAuth;
 import fr.xephi.authme.data.auth.PlayerCache;
 import fr.xephi.authme.datasource.DataSource;
+import fr.xephi.authme.initialization.factory.SingletonStore;
 import fr.xephi.authme.message.MessageKey;
 import fr.xephi.authme.permission.PermissionsManager;
 import fr.xephi.authme.process.AsynchronousProcess;
 import fr.xephi.authme.process.register.executors.RegistrationExecutor;
+import fr.xephi.authme.process.register.executors.RegistrationParameters;
+import fr.xephi.authme.process.register.executors.RegistrationMethod;
 import fr.xephi.authme.service.CommonService;
 import fr.xephi.authme.settings.properties.RegistrationSettings;
 import fr.xephi.authme.settings.properties.RestrictionSettings;
@@ -31,6 +34,8 @@ public class AsyncRegister implements AsynchronousProcess {
     private CommonService service;
     @Inject
     private PermissionsManager permissionsManager;
+    @Inject
+    private SingletonStore<RegistrationExecutor> registrationExecutorFactory;
 
     AsyncRegister() {
     }
@@ -38,12 +43,16 @@ public class AsyncRegister implements AsynchronousProcess {
     /**
      * Performs the registration process for the given player.
      *
-     * @param player the player to register
+     * @param variant the registration method
-     * @param executor the registration executor to perform the registration with
+     * @param parameters the parameters
+     * @param <P> parameters type
      */
-    public void register(Player player, RegistrationExecutor executor) {
+    public <P extends RegistrationParameters> void register(RegistrationMethod<P> variant, P parameters) {
-        if (preRegisterCheck(player) && executor.isRegistrationAdmitted()) {
+        if (preRegisterCheck(parameters.getPlayer())) {
-            executeRegistration(player, executor);
+            RegistrationExecutor<P> executor = registrationExecutorFactory.getSingleton(variant.getExecutorClass());
+            if (executor.isRegistrationAdmitted(parameters)) {
+                executeRegistration(parameters, executor);
+            }
         }
     }
 
@@ -66,15 +75,17 @@ public class AsyncRegister implements AsynchronousProcess {
     /**
      * Executes the registration.
      *
-     * @param player the player to register
+     * @param parameters the registration parameters
      * @param executor the executor to perform the registration process with
+     * @param <P> registration params type
      */
-    private void executeRegistration(Player player, RegistrationExecutor executor) {
+    private <P extends RegistrationParameters>
-        PlayerAuth auth = executor.buildPlayerAuth();
+            void executeRegistration(P parameters, RegistrationExecutor<P> executor) {
+        PlayerAuth auth = executor.buildPlayerAuth(parameters);
         if (database.saveAuth(auth)) {
-            executor.executePostPersistAction();
+            executor.executePostPersistAction(parameters);
         } else {
-            service.send(player, MessageKey.ERROR);
+            service.send(parameters.getPlayer(), MessageKey.ERROR);
         }
     }
 

src/main/java/fr/xephi/authme/process/register/executors/AbstractPasswordRegisterExecutor.java

@@ -0,0 +1,97 @@
+package fr.xephi.authme.process.register.executors;
+
+import fr.xephi.authme.data.auth.PlayerAuth;
+import fr.xephi.authme.process.SyncProcessManager;
+import fr.xephi.authme.process.login.AsynchronousLogin;
+import fr.xephi.authme.security.PasswordSecurity;
+import fr.xephi.authme.security.crypts.HashedPassword;
+import fr.xephi.authme.service.BukkitService;
+import fr.xephi.authme.service.CommonService;
+import fr.xephi.authme.service.ValidationService;
+import fr.xephi.authme.settings.properties.PluginSettings;
+import fr.xephi.authme.settings.properties.RegistrationSettings;
+import org.bukkit.entity.Player;
+
+import javax.inject.Inject;
+
+/**
+ * Registration executor for registration methods where the password
+ * is supplied by the user.
+ */
+abstract class AbstractPasswordRegisterExecutor<P extends AbstractPasswordRegisterParams>
+    implements RegistrationExecutor<P> {
+
+    /**
+     * Number of ticks to wait before running the login action when it is run synchronously.
+     * A small delay is necessary or the database won't return the newly saved PlayerAuth object
+     * and the login process thinks the user is not registered.
+     */
+    private static final int SYNC_LOGIN_DELAY = 5;
+
+    @Inject
+    private ValidationService validationService;
+
+    @Inject
+    private CommonService commonService;
+
+    @Inject
+    private PasswordSecurity passwordSecurity;
+
+    @Inject
+    private BukkitService bukkitService;
+
+    @Inject
+    private SyncProcessManager syncProcessManager;
+
+    @Inject
+    private AsynchronousLogin asynchronousLogin;
+
+    @Override
+    public boolean isRegistrationAdmitted(P params) {
+        ValidationService.ValidationResult passwordValidation = validationService.validatePassword(
+            params.getPassword(), params.getPlayer().getName());
+        if (passwordValidation.hasError()) {
+            commonService.send(params.getPlayer(), passwordValidation.getMessageKey(), passwordValidation.getArgs());
+            return false;
+        }
+        return true;
+    }
+
+    @Override
+    public PlayerAuth buildPlayerAuth(P params) {
+        HashedPassword hashedPassword = passwordSecurity.computeHash(params.getPassword(), params.getPlayerName());
+        params.setHashedPassword(hashedPassword);
+        return createPlayerAuthObject(params);
+    }
+
+    /**
+     * Creates the PlayerAuth object to store into the database, based on the registration parameters.
+     *
+     * @param params the parameters
+     * @return the PlayerAuth representing the new account to register
+     */
+    protected abstract PlayerAuth createPlayerAuthObject(P params);
+
+    /**
+     * Returns whether the player should be automatically logged in after registration.
+     *
+     * @param params the registration parameters
+     * @return true if the player should be logged in, false otherwise
+     */
+    protected boolean performLoginAfterRegister(P params) {
+        return !commonService.getProperty(RegistrationSettings.FORCE_LOGIN_AFTER_REGISTER);
+    }
+
+    @Override
+    public void executePostPersistAction(P params) {
+        final Player player = params.getPlayer();
+        if (performLoginAfterRegister(params)) {
+            if (commonService.getProperty(PluginSettings.USE_ASYNC_TASKS)) {
+                bukkitService.runTaskAsynchronously(() -> asynchronousLogin.forceLogin(player));
+            } else {
+                bukkitService.scheduleSyncDelayedTask(() -> asynchronousLogin.forceLogin(player), SYNC_LOGIN_DELAY);
+            }
+        }
+        syncProcessManager.processSyncPasswordRegister(player);
+    }
+}

src/main/java/fr/xephi/authme/process/register/executors/AbstractPasswordRegisterParams.java

@@ -0,0 +1,48 @@
+package fr.xephi.authme.process.register.executors;
+
+import fr.xephi.authme.security.crypts.HashedPassword;
+import org.bukkit.entity.Player;
+
+/**
+ * Common params type for implementors of {@link AbstractPasswordRegisterExecutor}.
+ * Password must be supplied on creation and cannot be changed later on. The {@link HashedPassword}
+ * is stored on the params object for later use.
+ */
+public abstract class AbstractPasswordRegisterParams extends RegistrationParameters {
+
+    private final String password;
+    private HashedPassword hashedPassword;
+
+    /**
+     * Constructor.
+     *
+     * @param player the player to register
+     * @param password the password to use
+     */
+    public AbstractPasswordRegisterParams(Player player, String password) {
+        super(player);
+        this.password = password;
+    }
+
+    /**
+     * Constructor with no defined password. Use for registration methods which
+     * have no implicit password (like two factor authentication).
+     *
+     * @param player the player to register
+     */
+    public AbstractPasswordRegisterParams(Player player) {
+        this(player, null);
+    }
+
+    public String getPassword() {
+        return password;
+    }
+
+    void setHashedPassword(HashedPassword hashedPassword) {
+        this.hashedPassword = hashedPassword;
+    }
+
+    HashedPassword getHashedPassword() {
+        return hashedPassword;
+    }
+}

src/main/java/fr/xephi/authme/process/register/executors/ApiPasswordRegisterExecutor.java

@@ -0,0 +1,20 @@
+package fr.xephi.authme.process.register.executors;
+
+import fr.xephi.authme.data.auth.PlayerAuth;
+
+/**
+ * Executor for password registration via API call.
+ */
+class ApiPasswordRegisterExecutor extends AbstractPasswordRegisterExecutor<ApiPasswordRegisterParams> {
+
+    @Override
+    protected PlayerAuth createPlayerAuthObject(ApiPasswordRegisterParams params) {
+        return PlayerAuthBuilderHelper
+            .createPlayerAuth(params.getPlayer(), params.getHashedPassword(), null);
+    }
+
+    @Override
+    protected boolean performLoginAfterRegister(ApiPasswordRegisterParams params) {
+        return params.getLoginAfterRegister();
+    }
+}

src/main/java/fr/xephi/authme/process/register/executors/ApiPasswordRegisterParams.java

@@ -0,0 +1,35 @@
+package fr.xephi.authme.process.register.executors;
+
+import org.bukkit.entity.Player;
+
+/**
+ * Parameters for {@link ApiPasswordRegisterExecutor}.
+ */
+public class ApiPasswordRegisterParams extends PasswordRegisterParams {
+
+    private final boolean loginAfterRegister;
+
+    protected ApiPasswordRegisterParams(Player player, String password, boolean loginAfterRegister) {
+        super(player, password, null);
+        this.loginAfterRegister = loginAfterRegister;
+    }
+
+    /**
+     * Creates a parameters object.
+     *
+     * @param player the player to register
+     * @param password the password to register with
+     * @param loginAfterRegister whether the player should be logged in after registration
+     * @return params object with the given data
+     */
+    public static ApiPasswordRegisterParams of(Player player, String password, boolean loginAfterRegister) {
+        return new ApiPasswordRegisterParams(player, password, loginAfterRegister);
+    }
+
+    /**
+     * @return true if the player should be logged in after being registered, false otherwise
+     */
+    public boolean getLoginAfterRegister() {
+        return loginAfterRegister;
+    }
+}

src/main/java/fr/xephi/authme/process/register/executors/EmailRegisterExecutor.java

@@ -0,0 +1,80 @@
+package fr.xephi.authme.process.register.executors;
+
+import fr.xephi.authme.data.auth.PlayerAuth;
+import fr.xephi.authme.datasource.DataSource;
+import fr.xephi.authme.mail.EmailService;
+import fr.xephi.authme.message.MessageKey;
+import fr.xephi.authme.permission.PermissionsManager;
+import fr.xephi.authme.process.SyncProcessManager;
+import fr.xephi.authme.security.PasswordSecurity;
+import fr.xephi.authme.security.crypts.HashedPassword;
+import fr.xephi.authme.service.CommonService;
+import fr.xephi.authme.settings.properties.EmailSettings;
+import fr.xephi.authme.util.RandomStringUtils;
+import org.bukkit.entity.Player;
+
+import javax.inject.Inject;
+
+import static fr.xephi.authme.permission.PlayerStatePermission.ALLOW_MULTIPLE_ACCOUNTS;
+import static fr.xephi.authme.process.register.executors.PlayerAuthBuilderHelper.createPlayerAuth;
+import static fr.xephi.authme.settings.properties.EmailSettings.RECOVERY_PASSWORD_LENGTH;
+
+/**
+ * Executor for email registration: the player only provides his email address,
+ * to which a generated password is sent.
+ */
+class EmailRegisterExecutor implements RegistrationExecutor<EmailRegisterParams> {
+
+    @Inject
+    private PermissionsManager permissionsManager;
+
+    @Inject
+    private DataSource dataSource;
+
+    @Inject
+    private CommonService commonService;
+
+    @Inject
+    private EmailService emailService;
+
+    @Inject
+    private SyncProcessManager syncProcessManager;
+
+    @Inject
+    private PasswordSecurity passwordSecurity;
+
+    @Override
+    public boolean isRegistrationAdmitted(EmailRegisterParams params) {
+        final int maxRegPerEmail = commonService.getProperty(EmailSettings.MAX_REG_PER_EMAIL);
+        if (maxRegPerEmail > 0 && !permissionsManager.hasPermission(params.getPlayer(), ALLOW_MULTIPLE_ACCOUNTS)) {
+            int otherAccounts = dataSource.countAuthsByEmail(params.getEmail());
+            if (otherAccounts >= maxRegPerEmail) {
+                commonService.send(params.getPlayer(), MessageKey.MAX_REGISTER_EXCEEDED,
+                    Integer.toString(maxRegPerEmail), Integer.toString(otherAccounts), "@");
+                return false;
+            }
+        }
+        return true;
+    }
+
+    @Override
+    public PlayerAuth buildPlayerAuth(EmailRegisterParams params) {
+        String password = RandomStringUtils.generate(commonService.getProperty(RECOVERY_PASSWORD_LENGTH));
+        HashedPassword hashedPassword = passwordSecurity.computeHash(password, params.getPlayer().getName());
+        params.setPassword(password);
+        return createPlayerAuth(params.getPlayer(), hashedPassword, params.getEmail());
+    }
+
+    @Override
+    public void executePostPersistAction(EmailRegisterParams params) {
+        Player player = params.getPlayer();
+        boolean couldSendMail = emailService.sendPasswordMail(
+            player.getName(), params.getEmail(), params.getPassword());
+        if (couldSendMail) {
+            syncProcessManager.processSyncEmailRegister(player);
+        } else {
+            commonService.send(player, MessageKey.EMAIL_SEND_FAILURE);
+        }
+    }
+
+}

src/main/java/fr/xephi/authme/process/register/executors/EmailRegisterExecutorProvider.java

@@ -1,91 +0,0 @@
-package fr.xephi.authme.process.register.executors;
-
-import fr.xephi.authme.data.auth.PlayerAuth;
-import fr.xephi.authme.datasource.DataSource;
-import fr.xephi.authme.mail.EmailService;
-import fr.xephi.authme.message.MessageKey;
-import fr.xephi.authme.permission.PermissionsManager;
-import fr.xephi.authme.process.SyncProcessManager;
-import fr.xephi.authme.security.PasswordSecurity;
-import fr.xephi.authme.security.crypts.HashedPassword;
-import fr.xephi.authme.service.CommonService;
-import fr.xephi.authme.settings.properties.EmailSettings;
-import fr.xephi.authme.util.RandomStringUtils;
-import org.bukkit.entity.Player;
-
-import javax.inject.Inject;
-
-import static fr.xephi.authme.permission.PlayerStatePermission.ALLOW_MULTIPLE_ACCOUNTS;
-import static fr.xephi.authme.process.register.executors.PlayerAuthBuilderHelper.createPlayerAuth;
-import static fr.xephi.authme.settings.properties.EmailSettings.RECOVERY_PASSWORD_LENGTH;
-
-/**
- * Provides a registration executor for email registration.
- */
-class EmailRegisterExecutorProvider {
-
-    @Inject
-    private PermissionsManager permissionsManager;
-
-    @Inject
-    private DataSource dataSource;
-
-    @Inject
-    private CommonService commonService;
-
-    @Inject
-    private EmailService emailService;
-
-    @Inject
-    private SyncProcessManager syncProcessManager;
-
-    @Inject
-    private PasswordSecurity passwordSecurity;
-
-    EmailRegisterExecutorProvider() {
-    }
-
-    /** Registration executor implementation for email registration. */
-    class EmailRegisterExecutor implements RegistrationExecutor {
-
-        private final Player player;
-        private final String email;
-        private String password;
-
-        EmailRegisterExecutor(Player player, String email) {
-            this.player = player;
-            this.email = email;
-        }
-
-        @Override
-        public boolean isRegistrationAdmitted() {
-            final int maxRegPerEmail = commonService.getProperty(EmailSettings.MAX_REG_PER_EMAIL);
-            if (maxRegPerEmail > 0 && !permissionsManager.hasPermission(player, ALLOW_MULTIPLE_ACCOUNTS)) {
-                int otherAccounts = dataSource.countAuthsByEmail(email);
-                if (otherAccounts >= maxRegPerEmail) {
-                    commonService.send(player, MessageKey.MAX_REGISTER_EXCEEDED, Integer.toString(maxRegPerEmail),
-                        Integer.toString(otherAccounts), "@");
-                    return false;
-                }
-            }
-            return true;
-        }
-
-        @Override
-        public PlayerAuth buildPlayerAuth() {
-            password = RandomStringUtils.generate(commonService.getProperty(RECOVERY_PASSWORD_LENGTH));
-            HashedPassword hashedPassword = passwordSecurity.computeHash(password, player.getName());
-            return createPlayerAuth(player, hashedPassword, email);
-        }
-
-        @Override
-        public void executePostPersistAction() {
-            boolean couldSendMail = emailService.sendPasswordMail(player.getName(), email, password);
-            if (couldSendMail) {
-                syncProcessManager.processSyncEmailRegister(player);
-            } else {
-                commonService.send(player, MessageKey.EMAIL_SEND_FAILURE);
-            }
-        }
-    }
-}

src/main/java/fr/xephi/authme/process/register/executors/EmailRegisterParams.java

@@ -0,0 +1,43 @@
+package fr.xephi.authme.process.register.executors;
+
+import org.bukkit.entity.Player;
+
+/**
+ * Parameters for email registration.
+ */
+public class EmailRegisterParams extends RegistrationParameters {
+
+    private final String email;
+    private String password;
+
+    protected EmailRegisterParams(Player player, String email) {
+        super(player);
+        this.email = email;
+    }
+
+    /**
+     * Creates a params object for email registration.
+     *
+     * @param player the player to register
+     * @param email the player's email
+     * @return params object with the given data
+     */
+    public static EmailRegisterParams of(Player player, String email) {
+        return new EmailRegisterParams(player, email);
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    void setPassword(String password) {
+        this.password = password;
+    }
+
+    /**
+     * @return the password generated for the player
+     */
+    String getPassword() {
+        return password;
+    }
+}

src/main/java/fr/xephi/authme/process/register/executors/PasswordRegisterExecutor.java

@@ -0,0 +1,17 @@
+package fr.xephi.authme.process.register.executors;
+
+import fr.xephi.authme.data.auth.PlayerAuth;
+
+import static fr.xephi.authme.process.register.executors.PlayerAuthBuilderHelper.createPlayerAuth;
+
+/**
+ * Registration executor for password registration.
+ */
+class PasswordRegisterExecutor extends AbstractPasswordRegisterExecutor<PasswordRegisterParams> {
+
+    @Override
+    public PlayerAuth createPlayerAuthObject(PasswordRegisterParams params) {
+        return createPlayerAuth(params.getPlayer(), params.getHashedPassword(), params.getEmail());
+    }
+
+}

src/main/java/fr/xephi/authme/process/register/executors/PasswordRegisterExecutorProvider.java

@@ -1,164 +0,0 @@
-package fr.xephi.authme.process.register.executors;
-
-import fr.xephi.authme.data.auth.PlayerAuth;
-import fr.xephi.authme.message.MessageKey;
-import fr.xephi.authme.process.SyncProcessManager;
-import fr.xephi.authme.process.login.AsynchronousLogin;
-import fr.xephi.authme.security.PasswordSecurity;
-import fr.xephi.authme.security.crypts.HashedPassword;
-import fr.xephi.authme.security.crypts.TwoFactor;
-import fr.xephi.authme.service.BukkitService;
-import fr.xephi.authme.service.CommonService;
-import fr.xephi.authme.service.ValidationService;
-import fr.xephi.authme.service.ValidationService.ValidationResult;
-import fr.xephi.authme.settings.properties.PluginSettings;
-import fr.xephi.authme.settings.properties.RegistrationSettings;
-import org.bukkit.Bukkit;
-import org.bukkit.entity.Player;
-
-import javax.inject.Inject;
-
-import static fr.xephi.authme.process.register.executors.PlayerAuthBuilderHelper.createPlayerAuth;
-
-/**
- * Provides registration executors for password-based registration variants.
- */
-class PasswordRegisterExecutorProvider {
-
-    /**
-     * Number of ticks to wait before running the login action when it is run synchronously.
-     * A small delay is necessary or the database won't return the newly saved PlayerAuth object
-     * and the login process thinks the user is not registered.
-     */
-    private static final int SYNC_LOGIN_DELAY = 5;
-
-    @Inject
-    private ValidationService validationService;
-
-    @Inject
-    private CommonService commonService;
-
-    @Inject
-    private PasswordSecurity passwordSecurity;
-
-    @Inject
-    private BukkitService bukkitService;
-
-    @Inject
-    private SyncProcessManager syncProcessManager;
-
-    @Inject
-    private AsynchronousLogin asynchronousLogin;
-
-    PasswordRegisterExecutorProvider() {
-    }
-
-    /** Registration executor for password registration. */
-    class PasswordRegisterExecutor implements RegistrationExecutor {
-
-        private final Player player;
-        private final String password;
-        private final String email;
-        private HashedPassword hashedPassword;
-
-        /**
-         * Constructor.
-         *
-         * @param player the player to register
-         * @param password the password to register with
-         * @param email the email of the player (may be null)
-         */
-        PasswordRegisterExecutor(Player player, String password, String email) {
-            this.player = player;
-            this.password = password;
-            this.email = email;
-        }
-
-        @Override
-        public boolean isRegistrationAdmitted() {
-            ValidationResult passwordValidation = validationService.validatePassword(password, player.getName());
-            if (passwordValidation.hasError()) {
-                commonService.send(player, passwordValidation.getMessageKey(), passwordValidation.getArgs());
-                return false;
-            }
-            return true;
-        }
-
-        @Override
-        public PlayerAuth buildPlayerAuth() {
-            hashedPassword = passwordSecurity.computeHash(password, player.getName().toLowerCase());
-            return createPlayerAuth(player, hashedPassword, email);
-        }
-
-        protected boolean performLoginAfterRegister() {
-            return !commonService.getProperty(RegistrationSettings.FORCE_LOGIN_AFTER_REGISTER);
-        }
-
-        @Override
-        public void executePostPersistAction() {
-            if (performLoginAfterRegister()) {
-                if (commonService.getProperty(PluginSettings.USE_ASYNC_TASKS)) {
-                    bukkitService.runTaskAsynchronously(() -> asynchronousLogin.forceLogin(player));
-                } else {
-                    bukkitService.scheduleSyncDelayedTask(() -> asynchronousLogin.forceLogin(player), SYNC_LOGIN_DELAY);
-                }
-            }
-            syncProcessManager.processSyncPasswordRegister(player);
-        }
-
-        protected Player getPlayer() {
-            return player;
-        }
-
-        protected HashedPassword getHashedPassword() {
-            return hashedPassword;
-        }
-    }
-
-    /** Executor for password registration via API call. */
-    class ApiPasswordRegisterExecutor extends PasswordRegisterExecutor {
-
-        private final boolean loginAfterRegister;
-
-        /**
-         * Constructor.
-         *
-         * @param player the player to register
-         * @param password the password to register with
-         * @param loginAfterRegister whether the user should be automatically logged in after registration
-         */
-        ApiPasswordRegisterExecutor(Player player, String password, boolean loginAfterRegister) {
-            super(player, password, null);
-            this.loginAfterRegister = loginAfterRegister;
-        }
-
-        @Override
-        protected boolean performLoginAfterRegister() {
-            return loginAfterRegister;
-        }
-    }
-
-    /** Executor for two factor registration. */
-    class TwoFactorRegisterExecutor extends PasswordRegisterExecutor {
-
-        TwoFactorRegisterExecutor(Player player) {
-            super(player, "", null);
-        }
-
-        @Override
-        public boolean isRegistrationAdmitted() {
-            // nothing to check
-            return true;
-        }
-
-        @Override
-        public void executePostPersistAction() {
-            super.executePostPersistAction();
-
-            String hash = getHashedPassword().getHash();
-            String qrCodeUrl = TwoFactor.getQRBarcodeURL(getPlayer().getName(), Bukkit.getIp(), hash);
-            commonService.send(getPlayer(), MessageKey.TWO_FACTOR_CREATE, hash, qrCodeUrl);
-        }
-
-    }
-}

src/main/java/fr/xephi/authme/process/register/executors/PasswordRegisterParams.java

@@ -0,0 +1,32 @@
+package fr.xephi.authme.process.register.executors;
+
+import org.bukkit.entity.Player;
+
+/**
+ * Parameters for registration with a given password, and optionally an email address.
+ */
+public class PasswordRegisterParams extends AbstractPasswordRegisterParams {
+
+    private final String email;
+
+    protected PasswordRegisterParams(Player player, String password, String email) {
+        super(player, password);
+        this.email = email;
+    }
+
+    /**
+     * Creates a params object.
+     *
+     * @param player the player to register
+     * @param password the password to register with
+     * @param email the email of the player (may be null)
+     * @return params object with the given data
+     */
+    public static PasswordRegisterParams of(Player player, String password, String email) {
+        return new PasswordRegisterParams(player, password, email);
+    }
+
+    public String getEmail() {
+        return email;
+    }
+}

src/main/java/fr/xephi/authme/process/register/executors/PlayerAuthBuilderHelper.java

@@ -13,6 +13,14 @@ final class PlayerAuthBuilderHelper {
     private PlayerAuthBuilderHelper() {
     }
 
+    /**
+     * Creates a {@link PlayerAuth} object with the given data.
+     *
+     * @param player the player to create a PlayerAuth for
+     * @param hashedPassword the hashed password
+     * @param email the email address (nullable)
+     * @return the generated PlayerAuth object
+     */
     static PlayerAuth createPlayerAuth(Player player, HashedPassword hashedPassword, String email) {
         return PlayerAuth.builder()
             .name(player.getName().toLowerCase())

src/main/java/fr/xephi/authme/process/register/executors/RegistrationExecutor.java

@@ -5,7 +5,7 @@ import fr.xephi.authme.data.auth.PlayerAuth;
 /**
  * Performs the registration action.
  */
-public interface RegistrationExecutor {
+public interface RegistrationExecutor<P extends RegistrationParameters> {
 
     /**
      * Returns whether the registration may take place. Use this method to execute
@@ -14,20 +14,24 @@ public interface RegistrationExecutor {
      * If this method returns {@code false}, it is expected that the executor inform
      * the player about the error within this method call.
      *
+     * @param params the parameters for the registration
      * @return true if registration may be performed, false otherwise
      */
-    boolean isRegistrationAdmitted();
+    boolean isRegistrationAdmitted(P params);
 
     /**
      * Constructs the PlayerAuth object to persist into the database.
      *
+     * @param params the parameters for the registration
      * @return the player auth to register in the data source
      */
-    PlayerAuth buildPlayerAuth();
+    PlayerAuth buildPlayerAuth(P params);
 
     /**
      * Follow-up method called after the player auth could be added into the database.
+     *
+     * @param params the parameters for the registration
      */
-    void executePostPersistAction();
+    void executePostPersistAction(P params);
 
 }

src/main/java/fr/xephi/authme/process/register/executors/RegistrationExecutorProvider.java

@@ -1,36 +0,0 @@
-package fr.xephi.authme.process.register.executors;
-
-import org.bukkit.entity.Player;
-
-import javax.inject.Inject;
-
-/**
- * Provides a {@link RegistrationExecutor} for various registration methods.
- */
-public class RegistrationExecutorProvider {
-
-    @Inject
-    private PasswordRegisterExecutorProvider passwordRegisterExecutorProvider;
-
-    @Inject
-    private EmailRegisterExecutorProvider emailRegisterExecutorProvider;
-
-    RegistrationExecutorProvider() {
-    }
-
-    public RegistrationExecutor getPasswordRegisterExecutor(Player player, String password, String email) {
-        return passwordRegisterExecutorProvider.new PasswordRegisterExecutor(player, password, email);
-    }
-
-    public RegistrationExecutor getPasswordRegisterExecutor(Player player, String password, boolean loginAfterRegister) {
-        return passwordRegisterExecutorProvider.new ApiPasswordRegisterExecutor(player, password, loginAfterRegister);
-    }
-
-    public RegistrationExecutor getTwoFactorRegisterExecutor(Player player) {
-        return passwordRegisterExecutorProvider.new TwoFactorRegisterExecutor(player);
-    }
-
-    public RegistrationExecutor getEmailRegisterExecutor(Player player, String email) {
-        return emailRegisterExecutorProvider.new EmailRegisterExecutor(player, email);
-    }
-}

src/main/java/fr/xephi/authme/process/register/executors/RegistrationMethod.java

@@ -0,0 +1,51 @@
+package fr.xephi.authme.process.register.executors;
+
+/**
+ * Methods with which a player can be registered.
+ * <p>
+ * These constants each define a different way of registering a player and define the
+ * {@link RegistrationParameters parameters} and {@link RegistrationExecutor executor}
+ * classes which perform this registration method. This is essentially a <i>typed enum</i>
+ * as passing a constant of this class along with a parameters object to a method can
+ * be restricted to the correct parameters type.
+ */
+public final class RegistrationMethod<P extends RegistrationParameters> {
+
+    /**
+     * Password registration.
+     */
+    public static final RegistrationMethod<PasswordRegisterParams> PASSWORD_REGISTRATION =
+        new RegistrationMethod<>(PasswordRegisterExecutor.class);
+
+    /**
+     * Registration with two-factor authentication as login means.
+     */
+    public static final RegistrationMethod<TwoFactorRegisterParams> TWO_FACTOR_REGISTRATION =
+        new RegistrationMethod<>(TwoFactorRegisterExecutor.class);
+
+    /**
+     * Email registration: an email address is provided, to which a generated password is sent.
+     */
+    public static final RegistrationMethod<EmailRegisterParams> EMAIL_REGISTRATION =
+        new RegistrationMethod<>(EmailRegisterExecutor.class);
+
+    /**
+     * API registration: player and password are provided via an API method.
+     */
+    public static final RegistrationMethod<ApiPasswordRegisterParams> API_REGISTRATION =
+        new RegistrationMethod<>(ApiPasswordRegisterExecutor.class);
+
+
+    private final Class<? extends RegistrationExecutor<P>> executorClass;
+
+    private RegistrationMethod(Class<? extends RegistrationExecutor<P>> executorClass) {
+        this.executorClass = executorClass;
+    }
+
+    /**
+     * @return the executor class to perform the registration method
+     */
+    public Class<? extends RegistrationExecutor<P>> getExecutorClass() {
+        return executorClass;
+    }
+}

src/main/java/fr/xephi/authme/process/register/executors/RegistrationParameters.java

@@ -0,0 +1,28 @@
+package fr.xephi.authme.process.register.executors;
+
+import org.bukkit.entity.Player;
+
+/**
+ * Parent of all registration parameters.
+ */
+public abstract class RegistrationParameters {
+
+    private final Player player;
+
+    /**
+     * Constructor.
+     *
+     * @param player the player to perform the registration for
+     */
+    public RegistrationParameters(Player player) {
+        this.player = player;
+    }
+
+    public Player getPlayer() {
+        return player;
+    }
+
+    public String getPlayerName() {
+        return player.getName();
+    }
+}

src/main/java/fr/xephi/authme/process/register/executors/TwoFactorRegisterExecutor.java

@@ -0,0 +1,43 @@
+package fr.xephi.authme.process.register.executors;
+
+import fr.xephi.authme.data.auth.PlayerAuth;
+import fr.xephi.authme.message.MessageKey;
+import fr.xephi.authme.security.crypts.TwoFactor;
+import fr.xephi.authme.service.CommonService;
+import org.bukkit.Bukkit;
+
+import javax.inject.Inject;
+
+import static fr.xephi.authme.process.register.executors.PlayerAuthBuilderHelper.createPlayerAuth;
+
+/**
+ * Executor for two-factor registration.
+ */
+class TwoFactorRegisterExecutor extends AbstractPasswordRegisterExecutor<TwoFactorRegisterParams> {
+
+    @Inject
+    private CommonService commonService;
+
+    @Override
+    public boolean isRegistrationAdmitted(TwoFactorRegisterParams params) {
+        // nothing to check
+        return true;
+    }
+
+    @Override
+    protected PlayerAuth createPlayerAuthObject(TwoFactorRegisterParams params) {
+        return createPlayerAuth(params.getPlayer(), params.getHashedPassword(), null);
+    }
+
+    @Override
+    public void executePostPersistAction(TwoFactorRegisterParams params) {
+        super.executePostPersistAction(params);
+
+        // Note ljacqu 20170317: This two-factor registration type is only invoked when the password hash is configured
+        // to two-factor authentication. Therefore, the hashed password is the result of the TwoFactor EncryptionMethod
+        // implementation (contains the TOTP secret).
+        String hash = params.getHashedPassword().getHash();
+        String qrCodeUrl = TwoFactor.getQRBarcodeURL(params.getPlayerName(), Bukkit.getIp(), hash);
+        commonService.send(params.getPlayer(), MessageKey.TWO_FACTOR_CREATE, hash, qrCodeUrl);
+    }
+}

src/main/java/fr/xephi/authme/process/register/executors/TwoFactorRegisterParams.java

@@ -0,0 +1,23 @@
+package fr.xephi.authme.process.register.executors;
+
+import org.bukkit.entity.Player;
+
+/**
+ * Parameters for registration with two-factor authentication.
+ */
+public class TwoFactorRegisterParams extends AbstractPasswordRegisterParams {
+
+    protected TwoFactorRegisterParams(Player player) {
+        super(player);
+    }
+
+    /**
+     * Creates a parameters object.
+     *
+     * @param player the player to register
+     * @return params object with the given player
+     */
+    public static TwoFactorRegisterParams of(Player player) {
+        return new TwoFactorRegisterParams(player);
+    }
+}

src/test/java/fr/xephi/authme/AuthMeInitializationTest.java

@@ -9,6 +9,7 @@ import fr.xephi.authme.command.CommandHandler;
 import fr.xephi.authme.datasource.DataSource;
 import fr.xephi.authme.initialization.DataFolder;
 import fr.xephi.authme.initialization.factory.FactoryDependencyHandler;
+import fr.xephi.authme.initialization.factory.SingletonStoreDependencyHandler;
 import fr.xephi.authme.listener.BlockListener;
 import fr.xephi.authme.permission.PermissionsManager;
 import fr.xephi.authme.process.Management;
@@ -93,7 +94,7 @@ public class AuthMeInitializationTest {
             new Settings(dataFolder, mock(PropertyResource.class), null, buildConfigurationData());
 
         Injector injector = new InjectorBuilder()
-            .addHandlers(new FactoryDependencyHandler())
+            .addHandlers(new FactoryDependencyHandler(), new SingletonStoreDependencyHandler())
             .addDefaultHandlers("fr.xephi.authme")
             .create();
         injector.provide(DataFolder.class, dataFolder);

src/test/java/fr/xephi/authme/ReflectionTestUtils.java

@@ -25,7 +25,7 @@ public final class ReflectionTestUtils {
      */
     public static <T> void setField(Class<T> clazz, T instance, String fieldName, Object value) {
         try {
-            Field field = getField(clazz, instance, fieldName);
+            Field field = getField(clazz, fieldName);
             field.set(instance, value);
         } catch (IllegalAccessException e) {
             throw new UnsupportedOperationException(
@@ -34,24 +34,30 @@ public final class ReflectionTestUtils {
         }
     }
 
-    private static <T> Field getField(Class<T> clazz, T instance, String fieldName) {
+    private static <T> Field getField(Class<T> clazz, String fieldName) {
         try {
             Field field = clazz.getDeclaredField(fieldName);
             field.setAccessible(true);
             return field;
         } catch (NoSuchFieldException e) {
-            throw new UnsupportedOperationException(format("Could not get field '%s' for instance '%s' of class '%s'",
+            throw new UnsupportedOperationException(format("Could not get field '%s' from class '%s'",
-                fieldName, instance, clazz.getName()), e);
+                fieldName, clazz.getName()), e);
         }
     }
 
     @SuppressWarnings("unchecked")
     public static <T, V> V getFieldValue(Class<T> clazz, T instance, String fieldName) {
-        Field field = getField(clazz, instance, fieldName);
+        Field field = getField(clazz, fieldName);
+        return getFieldValue(field, instance);
+    }
+
+    @SuppressWarnings("unchecked")
+    public static <V> V getFieldValue(Field field, Object instance) {
+        field.setAccessible(true);
         try {
             return (V) field.get(instance);
         } catch (IllegalAccessException e) {
-            throw new UnsupportedOperationException("Could not get value of field '" + fieldName + "'", e);
+            throw new UnsupportedOperationException("Could not get value of field '" + field.getName() + "'", e);
         }
     }
 

src/test/java/fr/xephi/authme/command/executable/register/RegisterCommandTest.java

@@ -1,13 +1,17 @@
 package fr.xephi.authme.command.executable.register;
 
+import fr.xephi.authme.ReflectionTestUtils;
 import fr.xephi.authme.TestHelper;
 import fr.xephi.authme.mail.EmailService;
 import fr.xephi.authme.message.MessageKey;
 import fr.xephi.authme.process.Management;
 import fr.xephi.authme.process.register.RegisterSecondaryArgument;
 import fr.xephi.authme.process.register.RegistrationType;
-import fr.xephi.authme.process.register.executors.RegistrationExecutor;
+import fr.xephi.authme.process.register.executors.EmailRegisterParams;
-import fr.xephi.authme.process.register.executors.RegistrationExecutorProvider;
+import fr.xephi.authme.process.register.executors.PasswordRegisterParams;
+import fr.xephi.authme.process.register.executors.RegistrationMethod;
+import fr.xephi.authme.process.register.executors.RegistrationParameters;
+import fr.xephi.authme.process.register.executors.TwoFactorRegisterParams;
 import fr.xephi.authme.security.HashAlgorithm;
 import fr.xephi.authme.service.CommonService;
 import fr.xephi.authme.service.ValidationService;
@@ -16,6 +20,9 @@ import fr.xephi.authme.settings.properties.SecuritySettings;
 import org.bukkit.command.BlockCommandSender;
 import org.bukkit.command.CommandSender;
 import org.bukkit.entity.Player;
+import org.hamcrest.Description;
+import org.hamcrest.Matcher;
+import org.hamcrest.TypeSafeMatcher;
 import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -24,10 +31,16 @@ import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.junit.MockitoJUnitRunner;
 
+import java.lang.reflect.Field;
+import java.lang.reflect.Modifier;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.List;
+import java.util.Objects;
 
 import static org.hamcrest.Matchers.containsString;
+import static org.junit.Assert.fail;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.BDDMockito.given;
@@ -57,9 +70,6 @@ public class RegisterCommandTest {
     @Mock
     private ValidationService validationService;
 
-    @Mock
-    private RegistrationExecutorProvider registrationExecutorProvider;
-
     @BeforeClass
     public static void setup() {
         TestHelper.setupLogger();
@@ -90,14 +100,13 @@ public class RegisterCommandTest {
         // given
         given(commonService.getProperty(SecuritySettings.PASSWORD_HASH)).willReturn(HashAlgorithm.TWO_FACTOR);
         Player player = mock(Player.class);
-        RegistrationExecutor executor = mock(RegistrationExecutor.class);
-        given(registrationExecutorProvider.getTwoFactorRegisterExecutor(player)).willReturn(executor);
 
         // when
         command.executeCommand(player, Collections.emptyList());
 
         // then
-        verify(management).performRegister(player, executor);
+        verify(management).performRegister(eq(RegistrationMethod.TWO_FACTOR_REGISTRATION),
+            argThat(isEqualTo(TwoFactorRegisterParams.of(player))));
         verifyZeroInteractions(emailService);
     }
 
@@ -208,8 +217,6 @@ public class RegisterCommandTest {
         given(commonService.getProperty(RegistrationSettings.REGISTER_SECOND_ARGUMENT)).willReturn(RegisterSecondaryArgument.CONFIRMATION);
         given(emailService.hasAllInformation()).willReturn(true);
         Player player = mock(Player.class);
-        RegistrationExecutor executor = mock(RegistrationExecutor.class);
-        given(registrationExecutorProvider.getEmailRegisterExecutor(player, playerMail)).willReturn(executor);
 
         // when
         command.executeCommand(player, Arrays.asList(playerMail, playerMail));
@@ -217,7 +224,8 @@ public class RegisterCommandTest {
         // then
         verify(validationService).validateEmail(playerMail);
         verify(emailService).hasAllInformation();
-        verify(management).performRegister(player, executor);
+        verify(management).performRegister(eq(RegistrationMethod.EMAIL_REGISTRATION),
+            argThat(isEqualTo(EmailRegisterParams.of(player, playerMail))));
     }
 
     @Test
@@ -239,14 +247,13 @@ public class RegisterCommandTest {
     public void shouldPerformPasswordRegistration() {
         // given
         Player player = mock(Player.class);
-        RegistrationExecutor executor = mock(RegistrationExecutor.class);
-        given(registrationExecutorProvider.getPasswordRegisterExecutor(player, "myPass", null)).willReturn(executor);
 
         // when
         command.executeCommand(player, Collections.singletonList("myPass"));
 
         // then
-        verify(management).performRegister(player, executor);
+        verify(management).performRegister(eq(RegistrationMethod.PASSWORD_REGISTRATION),
+            argThat(isEqualTo(PasswordRegisterParams.of(player, "myPass", null))));
     }
 
     @Test
@@ -257,15 +264,14 @@ public class RegisterCommandTest {
         String email = "email@example.org";
         given(validationService.validateEmail(email)).willReturn(true);
         Player player = mock(Player.class);
-        RegistrationExecutor executor = mock(RegistrationExecutor.class);
-        given(registrationExecutorProvider.getPasswordRegisterExecutor(player, "myPass", email)).willReturn(executor);
 
         // when
         command.executeCommand(player, Arrays.asList("myPass", email));
 
         // then
         verify(validationService).validateEmail(email);
-        verify(management).performRegister(player, executor);
+        verify(management).performRegister(eq(RegistrationMethod.PASSWORD_REGISTRATION),
+            argThat(isEqualTo(PasswordRegisterParams.of(player, "myPass", email))));
     }
 
     @Test
@@ -292,14 +298,64 @@ public class RegisterCommandTest {
         given(commonService.getProperty(RegistrationSettings.REGISTRATION_TYPE)).willReturn(RegistrationType.PASSWORD);
         given(commonService.getProperty(RegistrationSettings.REGISTER_SECOND_ARGUMENT)).willReturn(RegisterSecondaryArgument.EMAIL_OPTIONAL);
         Player player = mock(Player.class);
-        RegistrationExecutor executor = mock(RegistrationExecutor.class);
-        given(registrationExecutorProvider.getPasswordRegisterExecutor(eq(player), anyString(), eq(null))).willReturn(executor);
 
         // when
         command.executeCommand(player, Collections.singletonList("myPass"));
 
         // then
-        verify(registrationExecutorProvider).getPasswordRegisterExecutor(player, "myPass", null);
+        verify(management).performRegister(eq(RegistrationMethod.PASSWORD_REGISTRATION),
-        verify(management).performRegister(player, executor);
+            argThat(isEqualTo(PasswordRegisterParams.of(player, "myPass", null))));
+    }
+
+
+    // TODO ljacqu 20170317: Document and extract as util
+
+    private static <P extends RegistrationParameters> Matcher<P> isEqualTo(P expected) {
+        return new TypeSafeMatcher<P>() {
+            @Override
+            protected boolean matchesSafely(RegistrationParameters item) {
+                assertAreParamsEqual(expected, item);
+                return true;
+            }
+
+            @Override
+            public void describeTo(Description description) {
+                description.appendText("parameters " + expected);
+            }
+        };
+    }
+
+    private static void assertAreParamsEqual(RegistrationParameters lhs, RegistrationParameters rhs) {
+        if (lhs.getClass() != rhs.getClass()) {
+            fail("Params classes don't match, got " + lhs.getClass().getSimpleName()
+                + " and " + rhs.getClass().getSimpleName());
+        }
+
+        List<Field> fieldsToCheck = getFields(lhs);
+        for (Field field : fieldsToCheck) {
+            Object lhsValue = ReflectionTestUtils.getFieldValue(field, lhs);
+            Object rhsValue = ReflectionTestUtils.getFieldValue(field, rhs);
+            if (!Objects.equals(lhsValue, rhsValue)) {
+                fail("Field '" + field.getName() + "' does not have same value: '"
+                    + lhsValue + "' vs. '" + rhsValue + "'");
+            }
+        }
+    }
+
+    private static List<Field> getFields(RegistrationParameters params) {
+        List<Field> fields = new ArrayList<>();
+        Class<?> currentClass = params.getClass();
+        while (currentClass != null) {
+            for (Field f : currentClass.getDeclaredFields()) {
+                if (!Modifier.isStatic(f.getModifiers())) {
+                    fields.add(f);
+                }
+            }
+            if (currentClass == RegistrationParameters.class) {
+                break;
+            }
+            currentClass = currentClass.getSuperclass();
+        }
+        return fields;
     }
 }

src/test/java/fr/xephi/authme/process/register/AsyncRegisterTest.java

@@ -3,9 +3,13 @@ package fr.xephi.authme.process.register;
 import fr.xephi.authme.TestHelper;
 import fr.xephi.authme.data.auth.PlayerCache;
 import fr.xephi.authme.datasource.DataSource;
+import fr.xephi.authme.initialization.factory.SingletonStore;
 import fr.xephi.authme.message.MessageKey;
 import fr.xephi.authme.permission.PermissionsManager;
+import fr.xephi.authme.process.register.executors.PasswordRegisterParams;
 import fr.xephi.authme.process.register.executors.RegistrationExecutor;
+import fr.xephi.authme.process.register.executors.RegistrationMethod;
+import fr.xephi.authme.process.register.executors.TwoFactorRegisterParams;
 import fr.xephi.authme.service.CommonService;
 import fr.xephi.authme.settings.properties.RegistrationSettings;
 import fr.xephi.authme.settings.properties.RestrictionSettings;
@@ -16,6 +20,7 @@ import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.junit.MockitoJUnitRunner;
 
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.only;
@@ -39,6 +44,8 @@ public class AsyncRegisterTest {
     private CommonService commonService;
     @Mock
     private DataSource dataSource;
+    @Mock
+    private SingletonStore<RegistrationExecutor> registrationExecutorStore;
 
     @Test
     public void shouldDetectAlreadyLoggedInPlayer() {
@@ -47,9 +54,10 @@ public class AsyncRegisterTest {
         Player player = mockPlayerWithName(name);
         given(playerCache.isAuthenticated(name)).willReturn(true);
         RegistrationExecutor executor = mock(RegistrationExecutor.class);
+        singletonStoreWillReturn(registrationExecutorStore, executor);
 
         // when
-        asyncRegister.register(player, executor);
+        asyncRegister.register(RegistrationMethod.PASSWORD_REGISTRATION, PasswordRegisterParams.of(player, "abc", null));
 
         // then
         verify(commonService).send(player, MessageKey.ALREADY_LOGGED_IN_ERROR);
@@ -64,9 +72,10 @@ public class AsyncRegisterTest {
         given(playerCache.isAuthenticated(name)).willReturn(false);
         given(commonService.getProperty(RegistrationSettings.IS_ENABLED)).willReturn(false);
         RegistrationExecutor executor = mock(RegistrationExecutor.class);
+        singletonStoreWillReturn(registrationExecutorStore, executor);
 
         // when
-        asyncRegister.register(player, executor);
+        asyncRegister.register(RegistrationMethod.TWO_FACTOR_REGISTRATION, TwoFactorRegisterParams.of(player));
 
         // then
         verify(commonService).send(player, MessageKey.REGISTRATION_DISABLED);
@@ -82,9 +91,10 @@ public class AsyncRegisterTest {
         given(commonService.getProperty(RegistrationSettings.IS_ENABLED)).willReturn(true);
         given(dataSource.isAuthAvailable(name)).willReturn(true);
         RegistrationExecutor executor = mock(RegistrationExecutor.class);
+        singletonStoreWillReturn(registrationExecutorStore, executor);
 
         // when
-        asyncRegister.register(player, executor);
+        asyncRegister.register(RegistrationMethod.TWO_FACTOR_REGISTRATION, TwoFactorRegisterParams.of(player));
 
         // then
         verify(commonService).send(player, MessageKey.NAME_ALREADY_REGISTERED);
@@ -93,6 +103,7 @@ public class AsyncRegisterTest {
     }
 
     @Test
+    @SuppressWarnings("unchecked")
     public void shouldStopForFailedExecutorCheck() {
         // given
         String name = "edbert";
@@ -103,14 +114,16 @@ public class AsyncRegisterTest {
         given(commonService.getProperty(RestrictionSettings.MAX_REGISTRATION_PER_IP)).willReturn(0);
         given(dataSource.isAuthAvailable(name)).willReturn(false);
         RegistrationExecutor executor = mock(RegistrationExecutor.class);
-        given(executor.isRegistrationAdmitted()).willReturn(false);
+        TwoFactorRegisterParams params = TwoFactorRegisterParams.of(player);
+        given(executor.isRegistrationAdmitted(params)).willReturn(false);
+        singletonStoreWillReturn(registrationExecutorStore, executor);
 
         // when
-        asyncRegister.register(player, executor);
+        asyncRegister.register(RegistrationMethod.TWO_FACTOR_REGISTRATION, params);
 
         // then
         verify(dataSource, only()).isAuthAvailable(name);
-        verify(executor, only()).isRegistrationAdmitted();
+        verify(executor, only()).isRegistrationAdmitted(params);
     }
 
     private static Player mockPlayerWithName(String name) {
@@ -118,4 +131,10 @@ public class AsyncRegisterTest {
         given(player.getName()).willReturn(name);
         return player;
     }
+
+    @SuppressWarnings("unchecked")
+    private static void singletonStoreWillReturn(SingletonStore<RegistrationExecutor> store,
+                                                 RegistrationExecutor mock) {
+        given(store.getSingleton(any(Class.class))).willReturn(mock);
+    }
 }

src/test/java/fr/xephi/authme/process/register/executors/EmailRegisterExecutorProviderTest.java

@@ -1,6 +1,5 @@
 package fr.xephi.authme.process.register.executors;
 
-import fr.xephi.authme.ReflectionTestUtils;
 import fr.xephi.authme.TestHelper;
 import fr.xephi.authme.data.auth.PlayerAuth;
 import fr.xephi.authme.datasource.DataSource;
@@ -34,13 +33,13 @@ import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyZeroInteractions;
 
 /**
- * Test for {@link EmailRegisterExecutorProvider}.
+ * Test for {@link EmailRegisterExecutor}.
  */
 @RunWith(MockitoJUnitRunner.class)
 public class EmailRegisterExecutorProviderTest {
 
     @InjectMocks
-    private EmailRegisterExecutorProvider emailRegisterExecutorProvider;
+    private EmailRegisterExecutor executor;
 
     @Mock
     private PermissionsManager permissionsManager;
@@ -62,10 +61,10 @@ public class EmailRegisterExecutorProviderTest {
         String email = "test@example.com";
         given(dataSource.countAuthsByEmail(email)).willReturn(4);
         Player player = mock(Player.class);
-        RegistrationExecutor executor = emailRegisterExecutorProvider.new EmailRegisterExecutor(player, email);
+        EmailRegisterParams params = EmailRegisterParams.of(player, email);
 
         // when
-        boolean result = executor.isRegistrationAdmitted();
+        boolean result = executor.isRegistrationAdmitted(params);
 
         // then
         assertThat(result, equalTo(false));
@@ -80,10 +79,10 @@ public class EmailRegisterExecutorProviderTest {
         given(commonService.getProperty(EmailSettings.MAX_REG_PER_EMAIL)).willReturn(3);
         Player player = mock(Player.class);
         given(permissionsManager.hasPermission(player, PlayerStatePermission.ALLOW_MULTIPLE_ACCOUNTS)).willReturn(true);
-        RegistrationExecutor executor = emailRegisterExecutorProvider.new EmailRegisterExecutor(player, "test@example.com");
+        EmailRegisterParams params = EmailRegisterParams.of(player, "test@example.com");
 
         // when
-        boolean result = executor.isRegistrationAdmitted();
+        boolean result = executor.isRegistrationAdmitted(params);
 
         // then
         assertThat(result, equalTo(true));
@@ -97,10 +96,10 @@ public class EmailRegisterExecutorProviderTest {
         String email = "test@example.com";
         given(dataSource.countAuthsByEmail(email)).willReturn(0);
         Player player = mock(Player.class);
-        RegistrationExecutor executor = emailRegisterExecutorProvider.new EmailRegisterExecutor(player, "test@example.com");
+        EmailRegisterParams params = EmailRegisterParams.of(player, "test@example.com");
 
         // when
-        boolean result = executor.isRegistrationAdmitted();
+        boolean result = executor.isRegistrationAdmitted(params);
 
         // then
         assertThat(result, equalTo(true));
@@ -120,10 +119,10 @@ public class EmailRegisterExecutorProviderTest {
         World world = mock(World.class);
         given(world.getName()).willReturn("someWorld");
         given(player.getLocation()).willReturn(new Location(world, 48, 96, 144));
-        RegistrationExecutor executor = emailRegisterExecutorProvider.new EmailRegisterExecutor(player, "test@example.com");
+        EmailRegisterParams params = EmailRegisterParams.of(player, "test@example.com");
 
         // when
-        PlayerAuth auth = executor.buildPlayerAuth();
+        PlayerAuth auth = executor.buildPlayerAuth(params);
 
         // then
         assertThat(auth, hasAuthBasicData("veronica", "Veronica", "test@example.com", "123.45.67.89"));
@@ -132,18 +131,17 @@ public class EmailRegisterExecutorProviderTest {
     }
 
     @Test
-    @SuppressWarnings("unchecked")
     public void shouldPerformActionAfterDataSourceSave() {
         // given
         given(emailService.sendPasswordMail(anyString(), anyString(), anyString())).willReturn(true);
         Player player = mock(Player.class);
         given(player.getName()).willReturn("Laleh");
-        RegistrationExecutor executor = emailRegisterExecutorProvider.new EmailRegisterExecutor(player, "test@example.com");
+        EmailRegisterParams params = EmailRegisterParams.of(player, "test@example.com");
         String password = "A892C#@";
-        ReflectionTestUtils.setField((Class) executor.getClass(), executor, "password", password);
+        params.setPassword(password);
 
         // when
-        executor.executePostPersistAction();
+        executor.executePostPersistAction(params);
 
         // then
         verify(emailService).sendPasswordMail("Laleh", "test@example.com", password);
@@ -151,18 +149,17 @@ public class EmailRegisterExecutorProviderTest {
     }
 
     @Test
-    @SuppressWarnings("unchecked")
     public void shouldHandleEmailSendingFailure() {
         // given
         given(emailService.sendPasswordMail(anyString(), anyString(), anyString())).willReturn(false);
         Player player = mock(Player.class);
         given(player.getName()).willReturn("Laleh");
-        RegistrationExecutor executor = emailRegisterExecutorProvider.new EmailRegisterExecutor(player, "test@example.com");
+        EmailRegisterParams params = EmailRegisterParams.of(player, "test@example.com");
         String password = "A892C#@";
-        ReflectionTestUtils.setField((Class) executor.getClass(), executor, "password", password);
+        params.setPassword(password);
 
         // when
-        executor.executePostPersistAction();
+        executor.executePostPersistAction(params);
 
         // then
         verify(emailService).sendPasswordMail("Laleh", "test@example.com", password);

src/test/java/fr/xephi/authme/process/register/executors/PasswordRegisterExecutorTest.java

@@ -34,13 +34,13 @@ import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyZeroInteractions;
 
 /**
- * Test for {@link PasswordRegisterExecutorProvider}.
+ * Test for {@link PasswordRegisterExecutor}.
  */
 @RunWith(MockitoJUnitRunner.class)
-public class PasswordRegisterExecutorProviderTest {
+public class PasswordRegisterExecutorTest {
 
     @InjectMocks
-    private PasswordRegisterExecutorProvider passwordRegisterExecutorProvider;
+    private PasswordRegisterExecutor executor;
 
     @Mock
     private ValidationService validationService;
@@ -62,10 +62,10 @@ public class PasswordRegisterExecutorProviderTest {
         String name = "player040";
         given(validationService.validatePassword(password, name)).willReturn(new ValidationResult());
         Player player = mockPlayerWithName(name);
-        RegistrationExecutor executor = passwordRegisterExecutorProvider.new PasswordRegisterExecutor(player, password, null);
+        PasswordRegisterParams params = PasswordRegisterParams.of(player, password, null);
 
         // when
-        boolean result = executor.isRegistrationAdmitted();
+        boolean result = executor.isRegistrationAdmitted(params);
 
         // then
         assertThat(result, equalTo(true));
@@ -80,10 +80,10 @@ public class PasswordRegisterExecutorProviderTest {
         given(validationService.validatePassword(password, name)).willReturn(
             new ValidationResult(MessageKey.PASSWORD_CHARACTERS_ERROR, "[a-z]"));
         Player player = mockPlayerWithName(name);
-        RegistrationExecutor executor = passwordRegisterExecutorProvider.new PasswordRegisterExecutor(player, password, null);
+        PasswordRegisterParams params = PasswordRegisterParams.of(player, password, null);
 
         // when
-        boolean result = executor.isRegistrationAdmitted();
+        boolean result = executor.isRegistrationAdmitted(params);
 
         // then
         assertThat(result, equalTo(false));
@@ -101,10 +101,10 @@ public class PasswordRegisterExecutorProviderTest {
         World world = mock(World.class);
         given(world.getName()).willReturn("someWorld");
         given(player.getLocation()).willReturn(new Location(world, 48, 96, 144));
-        RegistrationExecutor executor = passwordRegisterExecutorProvider.new PasswordRegisterExecutor(player, "pass", "mail@example.org");
+        PasswordRegisterParams params = PasswordRegisterParams.of(player, "pass", "mail@example.org");
 
         // when
-        PlayerAuth auth = executor.buildPlayerAuth();
+        PlayerAuth auth = executor.buildPlayerAuth(params);
 
         // then
         assertThat(auth, hasAuthBasicData("s1m0n", "S1m0N", "mail@example.org", "123.45.67.89"));
@@ -118,10 +118,10 @@ public class PasswordRegisterExecutorProviderTest {
         given(commonService.getProperty(RegistrationSettings.FORCE_LOGIN_AFTER_REGISTER)).willReturn(false);
         given(commonService.getProperty(PluginSettings.USE_ASYNC_TASKS)).willReturn(false);
         Player player = mock(Player.class);
-        RegistrationExecutor executor = passwordRegisterExecutorProvider.new PasswordRegisterExecutor(player, "pass", "mail@example.org");
+        PasswordRegisterParams params = PasswordRegisterParams.of(player, "pass", "mail@example.org");
 
         // when
-        executor.executePostPersistAction();
+        executor.executePostPersistAction(params);
 
         // then
         TestHelper.runSyncDelayedTaskWithDelay(bukkitService);
@@ -134,10 +134,10 @@ public class PasswordRegisterExecutorProviderTest {
         // given
         given(commonService.getProperty(RegistrationSettings.FORCE_LOGIN_AFTER_REGISTER)).willReturn(true);
         Player player = mock(Player.class);
-        RegistrationExecutor executor = passwordRegisterExecutorProvider.new PasswordRegisterExecutor(player, "pass", "mail@example.org");
+        PasswordRegisterParams params = PasswordRegisterParams.of(player, "pass", "mail@example.org");
 
         // when
-        executor.executePostPersistAction();
+        executor.executePostPersistAction(params);
 
         // then
         verifyZeroInteractions(bukkitService, asynchronousLogin);