/** Returns true if the given height has a recorded checkpoint. */
public boolean isCheckpoint(int height) {
Sha256Hash checkpointHash = checkpoints.get(height);
return checkpointHash != null;
}
/**
* Returns true if the block height is either not a checkpoint, or is a checkpoint and the hash
* matches.
*/
public boolean passesCheckpoint(int height, Sha256Hash hash) {
Sha256Hash checkpointHash = checkpoints.get(height);
return checkpointHash == null || checkpointHash.equals(hash);
}