subprojects/s4-example/src/main/java/org/apache/s4/example/model/Module.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.s4.example.model;


import java.io.InputStream;

import org.apache.commons.configuration.ConfigurationConverter;
import org.apache.commons.configuration.ConfigurationException;
import org.apache.commons.configuration.ConfigurationUtils;
import org.apache.commons.configuration.PropertiesConfiguration;
import org.apache.s4.model.Model;

import com.google.inject.AbstractModule;
import com.google.inject.Binder;
import com.google.inject.name.Names;

/**
 * Configures the controller.
 * 
 * Reads a properties file, provides a {@link Communicator} singleton, and
 * configures Guice bindings.
 * 
 * @author Leo Neumeyer
 */
public class Module extends AbstractModule {

    protected PropertiesConfiguration config = null;

    private void loadProperties(Binder binder) {

        try {
            InputStream is = this.getClass().getResourceAsStream(
                    "/model.properties");
            config = new PropertiesConfiguration();
            config.load(is);

            System.out.println(ConfigurationUtils.toString(config));
            // TODO - validate properties.

            /* Make all properties injectable. Do we need this? */
            Names.bindProperties(binder,
                    ConfigurationConverter.getProperties(config));
        } catch (ConfigurationException e) {
            binder.addError(e);
            e.printStackTrace();
        }
    }

    @Override
    protected void configure() {
        if (config == null)
            loadProperties(binder());

        int vectorSize = config.getInt("model.vector_size");
        int numGaussians = config.getInt("model.num_gaussians");

        /*
         * Here we bind a specific Model implementation. This one is the
         * GaussianMixtureModel
         */
        bind(Model.class).toInstance(
                new org.apache.s4.model.GaussianMixtureModel(vectorSize, numGaussians,
                        org.apache.s4.model.GaussianMixtureModel.TrainMethod.STEP));

        /* Alternatively, we could bind to the GaussianModel. */
        // bind(Model.class).toInstance(
        // new org.apache.s4.model.GaussianModel(vectorSize, true));

    }
}