code: public String getParameter(String name, String defaultValue) {
  		String value = parameters.get(name);
  		if (value == null){
  			value = defaultValue;
  		}
  		return value;
  	}
docs: Gets a parameter extracted from the History token.
  For example, if the token is: <pre>{@code tokenId&param1=value1 }</pre>the call to <code>getParameter("param1", "def")</code> will return <code>value1</code>.
  
  @param name The name of the parameter
  @param defaultValue The value to be returned when the parameter value is <code>null</code>
  @return The value of the parameter, or <code>defaultValue</code> if not found.
  When the token is something like <pre>{@code tokenId&param1&param2 }</pre> with a name without a explicit value, an empty String is returned.