private <T> void mergeCounters(Counter<T> mine, Counter<?> theirCounter) {
checkArgument(
mine.isCompatibleWith(theirCounter),
"Can't merge CounterSets containing incompatible counters with the same name: "
+ "%s (existing) and %s (merged)",
mine,
theirCounter);
@SuppressWarnings("unchecked")
Counter<T> theirs = (Counter<T>) theirCounter;
mine.merge(theirs);
}
/**
* Adds the given Counter to this CounterSet.
*
* <p>If a counter with the same name already exists, it will be reused, as long as it is
* compatible.
*
* @return the Counter that was reused, or added
* @throws IllegalArgumentException if a counter with the same name but an incompatible kind had
* already been added
*/
public <T> Counter<T> addOrReuseCounter(Counter<T> counter) {
Counter<?> oldCounter = counters.putIfAbsent(counter.getUniqueName(), counter);
if (oldCounter != null) {
checkArgument(
counter.isCompatibleWith(oldCounter),
"Counter %s duplicates incompatible counter %s in %s",
counter,
oldCounter,
this);
// Return the counter to reuse.
@SuppressWarnings("unchecked")
Counter<T> compatibleCounter = (Counter<T>) oldCounter;
return compatibleCounter;
}
return counter;
}