fr.smartcontext.yatte.context.cli.properties.PropertiesContextInitializer.java Source code

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Here is the source code for fr.smartcontext.yatte.context.cli.properties.PropertiesContextInitializer.java

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/*******************************************************************************
 * Copyright (c) 2015 Goulwen Le Fur.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *******************************************************************************/
package fr.smartcontext.yatte.context.cli.properties;

import java.io.InputStream;
import java.lang.reflect.Field;
import java.net.URL;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Properties;
import java.util.Set;

import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.Options;

import fr.smartcontext.yatte.context.cli.ApplicationParametersConstants;
import fr.smartcontext.yatte.context.cli.CLIBasedContextInitializer;
import fr.smartcontext.yatte.engine.context.ProcessingContext;

/**
 * @author <a href="goulwen.lefur@gmail.com">Goulwen Le Fur</a>
 *
 */
public class PropertiesContextInitializer extends CLIBasedContextInitializer {

    /** 
     * {@inheritDoc}
     * @see fr.smartcontext.yatte.context.cli.CLIBasedContextInitializer#initContext(org.osgi.framework.BundleContext, java.util.List)
     */
    @Override
    public ProcessingContext initContext(List<String> parameters) throws Exception {
        ProcessingContext processingContext = super.initContext(parameters);
        Options options = getOptions();
        CommandLine cmdLine = getCmdLine(parameters, options);
        String propertiesPath = cmdLine.getOptionValue(ApplicationParametersConstants.PROPERTIES_PATH_OPTION_NAME);
        if (propertiesPath != null) {
            URL entry = new URL("file:" + propertiesPath);
            Properties prop = new Properties();
            InputStream openStream = entry.openStream();
            prop.load(openStream);
            Collection<String> searchVariableNames = searchVariableNames(prop);
            for (String varName : searchVariableNames) {
                Collection<String> features = searchFeatureForVariable(prop, varName);
                String type = prop.getProperty(varName + TYPE_SUFFIX);
                Class<?> class_ = processingContext.loadClass(type);
                Object instance = class_.newInstance();
                for (String feature : features) {
                    setFeature(prop, varName, class_, instance, feature);
                }
                processingContext.setVar(varName, instance);
            }
        }
        return processingContext;
    }

    private Collection<String> searchVariableNames(Properties properties) {
        Collection<String> result = new ArrayList<>();
        Set<Object> keySet = properties.keySet();
        for (Object key : keySet) {
            if (key instanceof String) {
                String str = (String) key;
                if (str.endsWith(TYPE_SUFFIX)) {
                    result.add(str.substring(0, str.length() - TYPE_SUFFIX.length()));
                }
            }
        }
        return result;
    }

    private Collection<String> searchFeatureForVariable(Properties properties, String varName) {
        Collection<String> result = new ArrayList<>();
        Set<Object> keySet = properties.keySet();
        for (Object key : keySet) {
            if (key instanceof String) {
                String str = (String) key;
                if (str.startsWith(varName + DOT) && !str.equals(varName + TYPE_SUFFIX)) {
                    result.add(str.substring((varName + DOT).length(), str.length()));
                }
            }
        }
        return result;
    }

    private void setFeature(Properties prop, String varName, Class<?> class_, Object instance, String feature)
            throws NoSuchFieldException, IllegalAccessException {
        String value = prop.getProperty(varName + DOT + feature);
        Field field = class_.getDeclaredField(feature);
        field.setAccessible(true);
        field.set(instance, value);
    }

}