public class BlockHandler {
   private BlockChain blockChain;

   // assume blockChain has the genesis block
   public BlockHandler(BlockChain bChain) {
      blockChain = bChain;
   }

   // add the block to the blockchain if it is valid and return true
   // else return false
   public boolean processBlock(Block block) {
      if (block == null)
         return false;
      return blockChain.addBlock(block);
   }

   // create a new block over the max height block
   public Block createBlock(RSAKey myAddress) {
      Block parent = blockChain.getMaxHeightBlock();
      byte[] parentHash = parent.getHash();
      Block current = new Block(parentHash, myAddress);
      UTXOPool uPool = blockChain.getMaxHeightUTXOPool();
      TransactionPool txPool = blockChain.getTransactionPool();
      TxHandler handler = new TxHandler(uPool);
      Transaction[] txs = txPool.getTransactions().toArray(new Transaction[0]);
      Transaction[] rTxs = handler.handleTxs(txs);
      for (int i = 0; i < rTxs.length; i++)
         current.addTransaction(rTxs[i]);

      current.finalize();
      if (blockChain.addBlock(current))
         return current;
      else
         return null;
   }

   // process a transaction
   public void processTx(Transaction tx) {
      blockChain.addTransaction(tx);
   }
}