public void clearTransactions(int fromHeight){
  lock.lock();
  try {
    if (fromHeight == 0) {
      unspent.clear();
      spent.clear();
      pending.clear();
      dead.clear();
      transactions.clear();
    }
 else {
      throw new UnsupportedOperationException();
    }
  }
  finally {
    lock.unlock();
  }
}

public void clearTransactions ( int fromHeight ) { lock . lock ( ) ; try { if ( fromHeight == 0 ) { unspent . clear ( ) ; spent . clear ( ) ; pending . clear ( ) ; dead . clear ( ) ; transactions . clear ( ) ; } else { throw new UnsupportedOperationException ( ) ; } } finally { lock . unlock ( ) ; } }
deletes transactions which appeared above the given block height from the wallet , but does not touch the keys . this is useful if you have some keys and wish to replay the block chain into the wallet in order to pick them up .
