public Long getMaxKey() {
		try (LockHold hold = LockHold.lock(lock.readLock())) {
			long max = table.getMaxKey();
			if (max == Long.MIN_VALUE) {
				return null;
			}
			return max;
		}
	}
Get the maximum key which has ever existed in this store

<p>
Note, the returned key may not actually be present

@return the maximum, or null if the store is unused
Ghidra/Debug/ProposedUtils/src/main/java/ghidra/util/database/DBCachedObjectStore.java