ConfigAdminUtil.java

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 * Copyright (c) 2008, 2009 Bug Labs, Inc.
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package com.buglabs.util;

import java.io.IOException;
import java.util.Dictionary;
import java.util.Hashtable;

import org.osgi.service.cm.Configuration;
import org.osgi.service.cm.ConfigurationAdmin;

/**
 * Static helper methods to work with the ConfigurationAdmin
 * 
 * @author kgilmer
 *
 */
public class ConfigAdminUtil {

	/**
	 * Get a config dictionary safely based on a ConfigurationAdmin service and a PID.  If configuration or properties do not exist it will be created.
	 * @param ca
	 * @return A dictionary
	 * @throws IOException 
	 */
	public static Dictionary getPropertiesSafely(ConfigurationAdmin ca, String pid) throws IOException {
		if (ca == null || pid == null) {
			throw new RuntimeException("Client called getPropertiesSafely() with null parameter.");
		}
		
		return getPropertiesSafely(ca.getConfiguration(pid));		
	}
	
	/**
	 * Given a Configuration return it's dictionary.  If a dictionary does not exist it will be created.
	 * @param config
	 * @return
	 * @throws IOException
	 */
	public static Dictionary getPropertiesSafely(Configuration config) throws IOException {
		if (config == null) {
			throw new RuntimeException("Client called getPropertiesSafely() with null parameter.");
		}		
		
		Dictionary properties = config.getProperties();
		
		if (properties == null) {
			properties = new Hashtable();
			
			config.update(properties);
		}
	
		return properties;
	}
	
	/**
	 * @param dict
	 * @param key
	 * @return true if dictionary contains key, false otherwise.
	 */
	public static boolean containsKey(Dictionary dict, String key) {
		if (dict == null || key == null) {
			return false;
		}
		
		return dict.get(key) != null;
	}
}