code: public synchronized boolean getAttribute(String key, boolean defaultValue)
  	{
  		if(attributes.containsKey(key))
  		{
  			Object obj = attributes.get(key);
  			if(obj instanceof Boolean)
  			{
  				return (Boolean) obj;
  			}
  		}
  		return defaultValue;
  	}
docs: /* (non-Javadoc)
  @see org.overture.ide.internal.core.resources.IOptionGroup#getAttribute(java.lang.String, boolean)