AbstractEagerActionHandlerValidatorRegistryImpl.java

/*
 * Copyright 2011 ArcBees Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.gwtplatform.dispatch.rpc.server.actionhandlervalidator;

import java.util.HashMap;
import java.util.Map;

import com.gwtplatform.dispatch.rpc.server.actionvalidator.ActionValidator;
import com.gwtplatform.dispatch.rpc.shared.Action;
import com.gwtplatform.dispatch.rpc.shared.Result;

/**
 * This is a eager-loading implementation of the registry. It will create action handlers and validators at startup. All
 * {@link com.gwtplatform.dispatch.rpc.server.actionhandler.ActionHandler ActionHandler} and {@link ActionValidator}
 * implementations <b>must</b> have a public, default constructor.
 */
public abstract class AbstractEagerActionHandlerValidatorRegistryImpl implements EagerActionHandlerValidatorRegistry {

    private final Map<Class<? extends Action<? extends Result>>, ActionHandlerValidatorInstance>
            actionHandlerValidatorInstances;
    private final Map<Class<? extends ActionValidator>, ActionValidator> validators;

    protected AbstractEagerActionHandlerValidatorRegistryImpl() {
        actionHandlerValidatorInstances = new HashMap<>();
        validators = new HashMap<>();
    }

    @Override
    public <A extends Action<R>, R extends Result> void addActionHandlerValidator(Class<A> actionClass,
            ActionHandlerValidatorInstance actionHandlerValidatorInstance) {
        actionHandlerValidatorInstances.put(actionClass, actionHandlerValidatorInstance);
        validators.put(actionHandlerValidatorInstance.getActionValidator().getClass(),
                actionHandlerValidatorInstance.getActionValidator());
    }

    @Override
    public void clearActionHandlerValidators() {
        actionHandlerValidatorInstances.clear();
        validators.clear();
    }

    @Override
    public <A extends Action<R>, R extends Result> ActionHandlerValidatorInstance findActionHandlerValidator(A action) {
        return actionHandlerValidatorInstances.get(action.getClass());
    }

    @Override
    public ActionValidator findActionValidator(Class<? extends ActionValidator> actionValidatorClass) {
        return validators.get(actionValidatorClass);
    }

    @Override
    public <A extends Action<R>, R extends Result> boolean removeActionHandlerValidator(Class<A> actionClass) {
        ActionHandlerValidatorInstance instance = actionHandlerValidatorInstances.remove(actionClass);

        if (instance != null) {
            if (!containValidator(instance.getActionValidator())) {
                return validators.remove(instance.getActionValidator().getClass()) != null;
            }
        } else {
            return false;
        }

        return actionHandlerValidatorInstances.remove(actionClass) != null;
    }

    private boolean containValidator(ActionValidator actionValidator) {
        for (ActionHandlerValidatorInstance validator : actionHandlerValidatorInstances.values()) {
            if (validator.getActionValidator().getClass().equals(actionValidator.getClass())) {
                return true;
            }
        }

        return false;
    }
}