/**
* Upgrades the priority of this object to the given priority.
*
* @param newPriority the new priority
* @throws IllegalArgumentException the given priority is less important than the current priority
*/
public void upgradePriority(Priority newPriority) throws IllegalArgumentException {
if (newPriority.numericalValue < priority.numericalValue) {
throw new IllegalArgumentException(
"Cannot upgrade to a less important priority ("
+ newPriority.toString()
+ "; current priority is: "
+ priority.toString()
+ ").");
}
priority = newPriority;
}
