Java Code Examples for org.bitcoinj.core.Block#getHash()

/**
 * Get a BlockInfo for the specified hash
 *
 * @param blockChain The blockchain object to pull the data from
 * @param blockHash The hash of the desired block
 * @param includeTx whether to include transactions (currently must be false)
 * @return block information (currently incomplete and untested)
 * @throws BlockStoreException Something went wrong
 */
private static BlockInfo getBlockInfoByHash(AbstractBlockChain blockChain, Sha256Hash blockHash, BlockInfo.IncludeTxFlag includeTx) throws BlockStoreException {
    if (includeTx == BlockInfo.IncludeTxFlag.YES) {
        throw new IllegalArgumentException("Including transactions not supported yet");
    }
    StoredBlock block = getStoredBlockByHash(blockChain, blockHash);
    Block header = block.getHeader();
    int blockHeight = block.getHeight();
    int confirmations = blockChain.getBestChainHeight() - blockHeight;
    log.trace("building BlockInfo for hash: {} height: {}", blockHash, blockHeight);
    return new BlockInfo(header.getHash(),
            confirmations,
            header.getMessageSize(),
            blockHeight,
            (int) header.getVersion(),
            header.getMerkleRoot(),
            -1,     // Unknown number of Transactions
            (includeTx == BlockInfo.IncludeTxFlag.IDONLY) ? hashListFromTxList(header.getTransactions()) : null,
            (int) header.getTimeSeconds(),
            header.getNonce(),
            null, // TODO: Return "bits" here
            new BigDecimal(header.getDifficultyTargetAsInteger()),  // TODO: Verify this is correct
            block.getChainWork().toString(),
            block.getPrev(blockChain.getBlockStore()).getHeader().getHash(),
            null);  // TODO: Extend BlockStore to make this information retrievable
}
 

public BlockSummary(int height, Block blk, TXUtil tx_util, Map<Sha256Hash, TransactionSummary> tx_cache)
{
  this.height = height;
  this.block_hash = blk.getHash();

  tx_map = new HashMap<>();

  for(Transaction tx : blk.getTransactions())
  {
    TransactionSummary tx_sum = new TransactionSummary(tx, tx_util, tx_cache);

    tx_map.put(tx.getHash(), tx_sum);
    synchronized(tx_cache)
    {
      tx_cache.put(tx.getHash(), tx_sum);
    }
  }
}
 

public void saveBlock(Block b)
{
    try
    {
      Sha256Hash hash = b.getHash();
      needed_prev_blocks.offer(b.getPrevBlockHash());
      int h = block_store.getHeight(hash);

      synchronized(in_progress)
      {
        if (!in_progress.containsKey(hash))
        {
          in_progress.put(hash, new Semaphore(0));
        }
      }

      jelly.getEventLog().log("Enqueing block: " + hash + " - " + h); 
      block_queue.put(b);
    }
    catch(java.lang.InterruptedException e)
    {
        throw new RuntimeException(e);
    }

}
 

@Test
public void testLastBlockSeenHash() throws Exception {
    // Test the lastBlockSeenHash field works.

    // LastBlockSeenHash should be empty if never set.
    Wallet wallet = new Wallet(UNITTEST);
    Protos.Wallet walletProto = new WalletProtobufSerializer().walletToProto(wallet);
    ByteString lastSeenBlockHash = walletProto.getLastSeenBlockHash();
    assertTrue(lastSeenBlockHash.isEmpty());

    // Create a block.
    Block block = UNITTEST.getDefaultSerializer()
            .makeBlock(ByteStreams.toByteArray(BlockTest.class.getResourceAsStream("block_testnet700000.dat")));
    Sha256Hash blockHash = block.getHash();
    wallet.setLastBlockSeenHash(blockHash);
    wallet.setLastBlockSeenHeight(1);

    // Roundtrip the wallet and check it has stored the blockHash.
    Wallet wallet1 = roundTrip(wallet);
    assertEquals(blockHash, wallet1.getLastBlockSeenHash());
    assertEquals(1, wallet1.getLastBlockSeenHeight());

    // Test the Satoshi genesis block (hash of all zeroes) is roundtripped ok.
    Block genesisBlock = MAINNET.getGenesisBlock();
    wallet.setLastBlockSeenHash(genesisBlock.getHash());
    Wallet wallet2 = roundTrip(wallet);
    assertEquals(genesisBlock.getHash(), wallet2.getLastBlockSeenHash());
}
 

public void put(Block b)
    throws org.bitcoinj.store.BlockStoreException
{
  Sha256Hash hash = b.getHash();
  Block header = b.cloneAsHeader();

  Sha256Hash prev = b.getPrevBlockHash();
  StoredBlock prev_sb = file_db.getBlockStoreMap().get(prev);

  StoredBlock sb = prev_sb.build(header);

  file_db.getBlockStoreMap().put(hash, sb);

  setChainHead(sb);
}
 

public void putAll(List<Block> blks)
    throws org.bitcoinj.store.BlockStoreException
{
  HashMap<Sha256Hash, StoredBlock> insert_map = new HashMap<>();

  StoredBlock last = null;

  for(Block b : blks)
  {
    Sha256Hash hash = b.getHash();
    Sha256Hash prev = b.getPrevBlockHash();

    if (!hash.equals(jelly.getNetworkParameters().getGenesisBlock().getHash()))
    {
      StoredBlock prev_sb = insert_map.get(prev);
      if (prev_sb == null)
      {
        prev_sb = file_db.getBlockStoreMap().get(prev);
      }
      Assert.assertNotNull(prev_sb);

      Block header = b.cloneAsHeader();
      StoredBlock sb = prev_sb.build(header);

      last = sb;

      insert_map.put(hash, sb);
    }
  }


  file_db.getBlockStoreMap().putAll(insert_map);

  if (last != null) setChainHead(last);

}
 

@Override
public void checkDifficultyTransitions(final StoredBlock storedPrev, final Block nextBlock,
                                       final BlockStore blockStore) throws VerificationException, BlockStoreException {
    final Block prev = storedPrev.getHeader();

    // Is this supposed to be a difficulty transition point?
    if (!isDifficultyTransitionPoint(storedPrev.getHeight())) {

        // No ... so check the difficulty didn't actually change.
        if (nextBlock.getDifficultyTarget() != prev.getDifficultyTarget())
            throw new VerificationException("Unexpected change in difficulty at height " + storedPrev.getHeight() +
                    ": " + Long.toHexString(nextBlock.getDifficultyTarget()) + " vs " +
                    Long.toHexString(prev.getDifficultyTarget()));
        return;
    }

    // We need to find a block far back in the chain. It's OK that this is expensive because it only occurs every
    // two weeks after the initial block chain download.
    final Stopwatch watch = Stopwatch.createStarted();
    Sha256Hash hash = prev.getHash();
    StoredBlock cursor = null;
    final int interval = this.getInterval();
    for (int i = 0; i < interval; i++) {
        cursor = blockStore.get(hash);
        if (cursor == null) {
            // This should never happen. If it does, it means we are following an incorrect or busted chain.
            throw new VerificationException(
                    "Difficulty transition point but we did not find a way back to the last transition point. Not found: " + hash);
        }
        hash = cursor.getHeader().getPrevBlockHash();
    }
    checkState(cursor != null && isDifficultyTransitionPoint(cursor.getHeight() - 1),
            "Didn't arrive at a transition point.");
    watch.stop();
    if (watch.elapsed(TimeUnit.MILLISECONDS) > 50)
        log.info("Difficulty transition traversal took {}", watch);

    Block blockIntervalAgo = cursor.getHeader();
    int timespan = (int) (prev.getTimeSeconds() - blockIntervalAgo.getTimeSeconds());
    // Limit the adjustment step.
    final int targetTimespan = this.getTargetTimespan();
    if (timespan < targetTimespan / 4)
        timespan = targetTimespan / 4;
    if (timespan > targetTimespan * 4)
        timespan = targetTimespan * 4;

    BigInteger newTarget = Utils.decodeCompactBits(prev.getDifficultyTarget());
    newTarget = newTarget.multiply(BigInteger.valueOf(timespan));
    newTarget = newTarget.divide(BigInteger.valueOf(targetTimespan));

    if (newTarget.compareTo(this.getMaxTarget()) > 0) {
        log.info("Difficulty hit proof of work limit: {}", newTarget.toString(16));
        newTarget = this.getMaxTarget();
    }

    int accuracyBytes = (int) (nextBlock.getDifficultyTarget() >>> 24) - 3;
    long receivedTargetCompact = nextBlock.getDifficultyTarget();

    // The calculated difficulty is to a higher precision than received, so reduce here.
    BigInteger mask = BigInteger.valueOf(0xFFFFFFL).shiftLeft(accuracyBytes * 8);
    newTarget = newTarget.and(mask);
    long newTargetCompact = Utils.encodeCompactBits(newTarget);

    if (newTargetCompact != receivedTargetCompact)
        throw new VerificationException("Network provided difficulty bits do not match what was calculated: " +
                Long.toHexString(newTargetCompact) + " vs " + Long.toHexString(receivedTargetCompact));
}
 

@Override
public void checkDifficultyTransitions(final StoredBlock storedPrev, final Block nextBlock,
	final BlockStore blockStore) throws VerificationException, BlockStoreException {
    final Block prev = storedPrev.getHeader();

    // Is this supposed to be a difficulty transition point?
    if (!isDifficultyTransitionPoint(storedPrev.getHeight())) {

        // No ... so check the difficulty didn't actually change.
        if (nextBlock.getDifficultyTarget() != prev.getDifficultyTarget())
            throw new VerificationException("Unexpected change in difficulty at height " + storedPrev.getHeight() +
                    ": " + Long.toHexString(nextBlock.getDifficultyTarget()) + " vs " +
                    Long.toHexString(prev.getDifficultyTarget()));
        return;
    }

    // We need to find a block far back in the chain. It's OK that this is expensive because it only occurs every
    // two weeks after the initial block chain download.
    final Stopwatch watch = Stopwatch.createStarted();
    Sha256Hash hash = prev.getHash();
    StoredBlock cursor = null;
    final int interval = this.getInterval();
    for (int i = 0; i < interval; i++) {
        cursor = blockStore.get(hash);
        if (cursor == null) {
            // This should never happen. If it does, it means we are following an incorrect or busted chain.
            throw new VerificationException(
                    "Difficulty transition point but we did not find a way back to the last transition point. Not found: " + hash);
        }
        hash = cursor.getHeader().getPrevBlockHash();
    }
    checkState(cursor != null && isDifficultyTransitionPoint(cursor.getHeight() - 1),
            "Didn't arrive at a transition point.");
    watch.stop();
    if (watch.elapsed(TimeUnit.MILLISECONDS) > 50)
        log.info("Difficulty transition traversal took {}", watch);

    Block blockIntervalAgo = cursor.getHeader();
    int timespan = (int) (prev.getTimeSeconds() - blockIntervalAgo.getTimeSeconds());
    // Limit the adjustment step.
    final int targetTimespan = this.getTargetTimespan();
    if (timespan < targetTimespan / 4)
        timespan = targetTimespan / 4;
    if (timespan > targetTimespan * 4)
        timespan = targetTimespan * 4;

    BigInteger newTarget = Utils.decodeCompactBits(prev.getDifficultyTarget());
    newTarget = newTarget.multiply(BigInteger.valueOf(timespan));
    newTarget = newTarget.divide(BigInteger.valueOf(targetTimespan));

    if (newTarget.compareTo(this.getMaxTarget()) > 0) {
        log.info("Difficulty hit proof of work limit: {}", newTarget.toString(16));
        newTarget = this.getMaxTarget();
    }

    int accuracyBytes = (int) (nextBlock.getDifficultyTarget() >>> 24) - 3;
    long receivedTargetCompact = nextBlock.getDifficultyTarget();

    // The calculated difficulty is to a higher precision than received, so reduce here.
    BigInteger mask = BigInteger.valueOf(0xFFFFFFL).shiftLeft(accuracyBytes * 8);
    newTarget = newTarget.and(mask);
    long newTargetCompact = Utils.encodeCompactBits(newTarget);

    if (newTargetCompact != receivedTargetCompact)
        throw new VerificationException("Network provided difficulty bits do not match what was calculated: " +
                Long.toHexString(newTargetCompact) + " vs " + Long.toHexString(receivedTargetCompact));
}
 

@Override
public void checkDifficultyTransitions(final StoredBlock storedPrev, final Block nextBlock,
	final BlockStore blockStore) throws VerificationException, BlockStoreException {
    final Block prev = storedPrev.getHeader();

    // Is this supposed to be a difficulty transition point?
    if (!isDifficultyTransitionPoint(storedPrev.getHeight())) {

        // No ... so check the difficulty didn't actually change.
        if (nextBlock.getDifficultyTarget() != prev.getDifficultyTarget())
            throw new VerificationException("Unexpected change in difficulty at height " + storedPrev.getHeight() +
                    ": " + Long.toHexString(nextBlock.getDifficultyTarget()) + " vs " +
                    Long.toHexString(prev.getDifficultyTarget()));
        return;
    }

    // We need to find a block far back in the chain. It's OK that this is expensive because it only occurs every
    // two weeks after the initial block chain download.
    final Stopwatch watch = Stopwatch.createStarted();
    Sha256Hash hash = prev.getHash();
    StoredBlock cursor = null;
    final int interval = this.getInterval();
    for (int i = 0; i < interval; i++) {
        cursor = blockStore.get(hash);
        if (cursor == null) {
            // This should never happen. If it does, it means we are following an incorrect or busted chain.
            throw new VerificationException(
                    "Difficulty transition point but we did not find a way back to the last transition point. Not found: " + hash);
        }
        hash = cursor.getHeader().getPrevBlockHash();
    }
    checkState(cursor != null && isDifficultyTransitionPoint(cursor.getHeight() - 1),
            "Didn't arrive at a transition point.");
    watch.stop();
    if (watch.elapsed(TimeUnit.MILLISECONDS) > 50)
        log.info("Difficulty transition traversal took {}", watch);

    Block blockIntervalAgo = cursor.getHeader();
    int timespan = (int) (prev.getTimeSeconds() - blockIntervalAgo.getTimeSeconds());
    // Limit the adjustment step.
    final int targetTimespan = this.getTargetTimespan();
    if (timespan < targetTimespan / 4)
        timespan = targetTimespan / 4;
    if (timespan > targetTimespan * 4)
        timespan = targetTimespan * 4;

    BigInteger newTarget = Utils.decodeCompactBits(prev.getDifficultyTarget());
    newTarget = newTarget.multiply(BigInteger.valueOf(timespan));
    newTarget = newTarget.divide(BigInteger.valueOf(targetTimespan));

    if (newTarget.compareTo(this.getMaxTarget()) > 0) {
        log.info("Difficulty hit proof of work limit: {}", newTarget.toString(16));
        newTarget = this.getMaxTarget();
    }

    int accuracyBytes = (int) (nextBlock.getDifficultyTarget() >>> 24) - 3;
    long receivedTargetCompact = nextBlock.getDifficultyTarget();

    // The calculated difficulty is to a higher precision than received, so reduce here.
    BigInteger mask = BigInteger.valueOf(0xFFFFFFL).shiftLeft(accuracyBytes * 8);
    newTarget = newTarget.and(mask);
    long newTargetCompact = Utils.encodeCompactBits(newTarget);

    if (newTargetCompact != receivedTargetCompact)
        throw new VerificationException("Network provided difficulty bits do not match what was calculated: " +
                Long.toHexString(newTargetCompact) + " vs " + Long.toHexString(receivedTargetCompact));
}