SystemProperties.java

/*
 * JABM - Java Agent-Based Modeling Toolkit
 * Copyright (C) 2013 Steve Phelps
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 3 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 */
package net.sourceforge.jabm.util;

import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Properties;
import java.util.Set;

/**
 * <p>
 * A set of property bindings that are initialised from system properties passed
 * on the command line (typically using the "-D" option). All property names are
 * assumed to be in the form <code>basename.suffix</code> where
 * <code>basename</code> is common to all properties. The <code>basename</code>
 * will typically correspond to the name of a class or application. When
 * constructing the class a set of legal suffixes is specified. If a system
 * property is found with the specified <code><basename></code> but an illegal
 * suffix then an <code>IllegalArgumentExpcetion</code> will be thrown.
 * 
 * @see <code>System.getProperty()</code>
 *      </p>
 * 
 * @author sphelps
 */
public class SystemProperties extends Properties {

	protected String baseName;

	protected Set<String> propertyNames;
	
	protected static SystemProperties jabsConfiguration = null;

	public static final String PROPERTY_BASE = "jabm";

	public static final String PROPERTY_BASE_DIR_NAME = "basedirname";
	public static final String PROPERTY_PROPFILE = "propertyfile";
	public static final String PROPERTY_CONFIG_ONLY = "configonly";
	public static final String PROPERTY_VARFILE = "varfile";
	public static final String PROPERTY_CONFIG = "config";
	public static final String PROPERTY_SEEDS = "genseeds";
	public static final String PROPERTY_SEED_MASK = "seedmask";

	public static final String[] jabmProperties = new String[] {
			PROPERTY_SEEDS, PROPERTY_SEED_MASK, PROPERTY_BASE_DIR_NAME, 
			PROPERTY_PROPFILE, PROPERTY_CONFIG_ONLY, PROPERTY_VARFILE, 
			PROPERTY_CONFIG };

	public SystemProperties(String baseName, Set<String> propertyNames,
			HashMap<String, String> defaultBindings)
			throws IllegalArgumentException {
		super();
		this.baseName = baseName;
		this.propertyNames = propertyNames;
		readSystemProperties();
	}
	
	public SystemProperties(String baseName, Collection<String> propertyNames) {
		this(baseName, new HashSet<String>(propertyNames),
				new HashMap<String, String>());
	}
	
	public SystemProperties(String baseName, String[] propertyNames) {
		this(baseName, Arrays.asList(propertyNames));
	}

	public void readSystemProperties() throws IllegalArgumentException {
		Properties systemProperties = System.getProperties();
		for (Object property : systemProperties.keySet()) {
			String propertyName = property.toString();
			if (propertyName.startsWith(baseName + ".")) {
				propertyName = propertyName.substring(baseName.length() + 1);
				if (propertyNames.contains(propertyName)) {
					String value = null;
					String fullPropertyName = baseName + "." + propertyName;
					value = System.getProperty(fullPropertyName);
					if (value != null) {
						super.setProperty(propertyName, value);
					}
				} else {
					throw new IllegalArgumentException("Invalid property: "
							+ propertyName);
				}
			}
		}
	}
	
	public static SystemProperties jabsConfiguration() {
		if (jabsConfiguration == null) {
			jabsConfiguration = 
				new SystemProperties(PROPERTY_BASE, jabmProperties);
		}
		return jabsConfiguration;
	}
}