nl.tudelft.graphalytics.configuration.ConfigurationUtil.java Source code

Introduction

Here is the source code for nl.tudelft.graphalytics.configuration.ConfigurationUtil.java

Source

/*
 * Copyright 2015 Delft University of Technology
 *
 * 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 nl.tudelft.graphalytics.configuration;

import org.apache.commons.configuration.Configuration;
import org.apache.commons.configuration.ConversionException;
import org.apache.commons.configuration.SubsetConfiguration;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

/**
 * Utility class for parsing the benchmark configuration. The get-functions throw a descriptive exception if the
 * requested property does not exist or contains a value incompatible with the requested type.
 *
 * @author Tim Hegeman
 */
public final class ConfigurationUtil {

    private static final Logger LOG = LogManager.getLogger();

    /**
     * Prevent instantiation of utility class.
     */
    private ConfigurationUtil() {
    }

    public static void ensureConfigurationKeyExists(Configuration config, String property)
            throws InvalidConfigurationException {
        if (!config.containsKey(property)) {
            throw new InvalidConfigurationException("Missing property: \"" + resolve(config, property) + "\".");
        }
    }

    public static String getString(Configuration config, String property) throws InvalidConfigurationException {
        ensureConfigurationKeyExists(config, property);
        return config.getString(property);
    }

    public static String[] getStringArray(Configuration config, String property)
            throws InvalidConfigurationException {
        ensureConfigurationKeyExists(config, property);
        return config.getStringArray(property);
    }

    public static boolean getBoolean(Configuration config, String property) throws InvalidConfigurationException {
        ensureConfigurationKeyExists(config, property);
        try {
            return config.getBoolean(property);
        } catch (ConversionException ignore) {
            throw new InvalidConfigurationException("Invalid value for property \"" + resolve(config, property)
                    + "\": \"" + config.getString(property) + "\", expected a boolean value.");
        }
    }

    public static int getInteger(Configuration config, String property) throws InvalidConfigurationException {
        ensureConfigurationKeyExists(config, property);
        try {
            return config.getInt(property);
        } catch (ConversionException ignore) {
            throw new InvalidConfigurationException("Invalid value for property \"" + resolve(config, property)
                    + "\": \"" + config.getString(property) + "\", expected an integer value.");
        }
    }

    public static long getLong(Configuration config, String property) throws InvalidConfigurationException {
        ensureConfigurationKeyExists(config, property);
        try {
            return config.getLong(property);
        } catch (ConversionException ignore) {
            throw new InvalidConfigurationException("Invalid value for property \"" + resolve(config, property)
                    + "\": \"" + config.getString(property) + "\", expected a long value.");
        }
    }

    public static long getLongOrWarn(Configuration config, String property, long defaultValue) {
        try {
            return getLong(config, property);
        } catch (InvalidConfigurationException ex) {
            LOG.warn("Failed to read property \"" + resolve(config, property) + "\", defaulting to " + defaultValue
                    + ".", ex);
            return defaultValue;
        }
    }

    public static float getFloat(Configuration config, String property) throws InvalidConfigurationException {
        ensureConfigurationKeyExists(config, property);
        try {
            return config.getFloat(property);
        } catch (ConversionException ignore) {
            throw new InvalidConfigurationException("Invalid value for property \"" + resolve(config, property)
                    + "\": \"" + config.getString(property) + "\", expected a floating point value.");
        }
    }

    public static double getDouble(Configuration config, String property) throws InvalidConfigurationException {
        ensureConfigurationKeyExists(config, property);
        try {
            return config.getDouble(property);
        } catch (ConversionException ignore) {
            throw new InvalidConfigurationException("Invalid value for property \"" + resolve(config, property)
                    + "\": \"" + config.getString(property) + "\", expected a double value.");
        }
    }

    public static char getChar(Configuration config, String property) throws InvalidConfigurationException {
        String stringValue = getString(config, property);
        if (stringValue.length() == 1) {
            return stringValue.charAt(0);
        } else if (stringValue.length() == 3 && stringValue.charAt(0) == stringValue.charAt(2)
                && (stringValue.charAt(0) == '\"' || stringValue.charAt(0) == '\'')) {
            // Extract char when surrounded by quotes
            return stringValue.charAt(1);
        } else {
            throw new InvalidConfigurationException("Invalid value for property \"" + resolve(config, property)
                    + "\": \"" + config.getString(property) + "\", expected a single character.");
        }
    }

    public static String resolve(Configuration config, String property) {
        String fullProperty = property;
        while (config instanceof SubsetConfiguration) {
            fullProperty = ((SubsetConfiguration) config).getPrefix() + "." + fullProperty;
            config = ((SubsetConfiguration) config).getParent();
        }
        return fullProperty;
    }

}