HandlerModule.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.guice;

import com.google.inject.AbstractModule;
import com.google.inject.internal.UniqueAnnotations;
import com.gwtplatform.dispatch.rpc.server.actionhandler.ActionHandler;
import com.gwtplatform.dispatch.rpc.server.actionhandlervalidator.ActionHandlerValidatorClass;
import com.gwtplatform.dispatch.rpc.server.actionhandlervalidator.ActionHandlerValidatorMap;
import com.gwtplatform.dispatch.rpc.server.actionhandlervalidator.ActionHandlerValidatorMapImpl;
import com.gwtplatform.dispatch.rpc.server.actionvalidator.ActionValidator;
import com.gwtplatform.dispatch.rpc.server.guice.actionvalidator.DefaultActionValidator;
import com.gwtplatform.dispatch.rpc.shared.Action;
import com.gwtplatform.dispatch.rpc.shared.Result;

/**
 * Base module that will bind {@link Action}s to {@link ActionHandler}s and {@link ActionValidator}s.
 * Your own Guice modules should extend this class.
 */
public abstract class HandlerModule extends AbstractModule {

    private final DispatchModule dispatchModule;

    /**
     * Constructs a HandlerModule that uses the {@link DispatchModule} with
     * default configuration.
     */
    public HandlerModule() {
        this.dispatchModule = new DispatchModule();
    }

    /**
     * Constructs a {@link HandlerModule} that uses the {@link DispatchModule} with a custom configuration.
     *
     * @param dispatchModule The custom configured {@link DispatchModule}
     */
    public HandlerModule(DispatchModule dispatchModule) {
        this.dispatchModule = dispatchModule;
    }

    /**
     * @param <A>          Type of {@link Action}
     * @param <R>          Type of {@link Result}
     * @param actionClass  Implementation of {@link Action} to link and bind
     * @param handlerClass Implementation of {@link ActionHandler} to link and bind
     */
    protected <A extends Action<R>, R extends Result> void bindHandler(
            Class<A> actionClass, Class<? extends ActionHandler<A, R>> handlerClass) {
        bind(ActionHandlerValidatorMap.class).annotatedWith(
                UniqueAnnotations.create()).toInstance(
                new ActionHandlerValidatorMapImpl<>(actionClass,
                        new ActionHandlerValidatorClass<>(handlerClass,
                                DefaultActionValidator.class)));
    }

    /**
     * @param <A>             Type of {@link Action}
     * @param <R>             Type of {@link Result}
     * @param actionClass     Implementation of {@link Action} to link and bind
     * @param handlerClass    Implementation of {@link ActionHandler} to link and bind
     * @param actionValidator Implementation of {@link ActionValidator} to link and bind
     */
    protected <A extends Action<R>, R extends Result> void bindHandler(
            Class<A> actionClass, Class<? extends ActionHandler<A, R>> handlerClass,
            Class<? extends ActionValidator> actionValidator) {
        bind(ActionHandlerValidatorMap.class).annotatedWith(
                UniqueAnnotations.create()).toInstance(
                new ActionHandlerValidatorMapImpl<>(
                        actionClass,
                        new ActionHandlerValidatorClass<>(handlerClass, actionValidator)));
    }

    @Override
    protected final void configure() {
        install(dispatchModule);
        configureHandlers();
    }

    /**
     * Override this method to configure your handlers. Use calls to {@link #bindHandler} to register actions that do
     * not need any specific security validation.
     */
    protected abstract void configureHandlers();
}