MvcConverterModule.java

/*****************************************************************************
 * Copyright 2012 Zdenko Vrabel
 *
 * 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 org.zdevra.guice.mvc;

import org.zdevra.guice.mvc.ConversionService.ConverterFactory;

import com.google.inject.AbstractModule;

/**
 * It's regular Guice's abstract module but it's enriched 
 * by methods which provides converter registration.
 */
public abstract class MvcConverterModule extends AbstractModule {

    /** all binders for service {@link ConverterFactory services} */
    private MultibinderBuilder<ConverterFactory> conversionServiceBuilder;

    /**
     * In this method you will setup your converters
     */
    protected abstract void configureConverters();


    /**
     * {@inheritDoc}
     */
    @Override
    protected final void configure() {
        try {
            conversionServiceBuilder = new MultibinderBuilder<ConverterFactory>(binder(), ConverterFactory.class);
            configureConverters();
        } finally {
            conversionServiceBuilder = null;
        }
    }

    /**
     * The method registers a custom converter which converts strings to the
     * concrete types. These converters are used for conversions from a HTTP request 
     * to the method's parameters.
     * 
     * The all predefined default converters are placed in the 'converters' sub-package.  
     */
    protected final void registerConverter(ConverterFactory converterFactory) {
        this.conversionServiceBuilder.registerInstance(converterFactory);
    }

    /**
     * The method registers a custom converter which converts strings to the
     * concrete types. These converters are used for conversions from a HTTP request 
     * to the method's parameters.
     * 
     * The all predefined default convertors are placed in the 'converters' sub-package.  
     */
    protected final void registerConverter(Class<? extends ConverterFactory> convertorFactoryClazz) {
        this.conversionServiceBuilder.registerClass(convertorFactoryClazz);
    }
}