CHANGED: added support for DB transactions (commit/rollback) to repository

src/database/DB.java

@@ -68,6 +68,10 @@ public abstract class DB {
 		return local.get();
 	}
 
+	public static Connection getPoolConnection() throws SQLException {
+		return connectionPool.getConnection();
+	}
+	
 	public static void releaseConnection() {
 		Connection connection = local.get();
 		if (connection != null)
@@ -179,7 +183,12 @@ public abstract class DB {
 	 * @throws SQLException
 	 */
 	public static ResultSet checkedExecute(String sql, Object... objects) throws SQLException {
-		PreparedStatement preparedStatement = DB.getConnection().prepareStatement(sql);
+		Connection connection = DB.getConnection();
+		return checkedExecute(connection, sql, objects);
+	}
+
+	public static ResultSet checkedExecute(Connection connection, String sql, Object... objects) throws SQLException {
+		PreparedStatement preparedStatement = connection.prepareStatement(sql);
 
 		for (int i = 0; i < objects.length; ++i)
 			// Special treatment for BigDecimals so that they retain their "scale",

src/repository/Repository.java

@@ -5,6 +5,10 @@ public abstract class Repository {
 	protected TransactionRepository transactionRepository;
 	protected BlockRepository blockRepository;
 
+	public abstract void saveChanges() throws DataException ;
+	public abstract void discardChanges() throws DataException ;
+	public abstract void close() throws DataException ;
+	
 	public TransactionRepository getTransactionRepository() {
 		return this.transactionRepository;
 	}

src/repository/hsqldb/HSQLDBBlockRepository.java

@@ -22,11 +22,17 @@ public class HSQLDBBlockRepository implements BlockRepository
 	private static final String BLOCK_DB_COLUMNS = "version, reference, transaction_count, total_fees, "
 			+ "transactions_signature, height, generation, generating_balance, generator, generator_signature, AT_data, AT_fees";
 
+	protected HSQLDBRepository repository;
+	
+	public HSQLDBBlockRepository(HSQLDBRepository repository) {
+		this.repository = repository;
+	}
+	
 	public BlockData fromSignature(byte[] signature) throws DataException
 	{		
 		ResultSet rs;
 		try {
-			rs = DB.checkedExecute("SELECT " + BLOCK_DB_COLUMNS + " FROM Blocks WHERE signature = ?", signature);
+			rs = DB.checkedExecute(repository.connection, "SELECT " + BLOCK_DB_COLUMNS + " FROM Blocks WHERE signature = ?", signature);
 		} catch (SQLException e) {
 			throw new DataException("Error loading data from DB", e);
 		}
@@ -37,7 +43,7 @@ public class HSQLDBBlockRepository implements BlockRepository
 	{		
 		ResultSet rs;
 		try {
-			rs = DB.checkedExecute("SELECT " + BLOCK_DB_COLUMNS + " FROM Blocks WHERE height = ?", height);
+			rs = DB.checkedExecute(repository.connection, "SELECT " + BLOCK_DB_COLUMNS + " FROM Blocks WHERE height = ?", height);
 		} catch (SQLException e) {
 			throw new DataException("Error loading data from DB", e);
 		}
@@ -45,20 +51,26 @@ public class HSQLDBBlockRepository implements BlockRepository
 	}
 
 	private BlockData getBlockFromResultSet(ResultSet rs) throws DataException {
-		int version = rs.getInt(1);
+		try {
-		byte[] reference = DB.getResultSetBytes(rs.getBinaryStream(2), REFERENCE_LENGTH);
+			int version = rs.getInt(1);
-		int transactionCount = rs.getInt(3);
+			byte[] reference = DB.getResultSetBytes(rs.getBinaryStream(2));
-		BigDecimal totalFees = rs.getBigDecimal(4);
+			int transactionCount = rs.getInt(3);
-		byte[] transactionsSignature = DB.getResultSetBytes(rs.getBinaryStream(5), TRANSACTIONS_SIGNATURE_LENGTH);
+			BigDecimal totalFees = rs.getBigDecimal(4);
-		int height = rs.getInt(6);
+			byte[] transactionsSignature = DB.getResultSetBytes(rs.getBinaryStream(5));
-		long timestamp = rs.getTimestamp(7).getTime();
+			int height = rs.getInt(6);
-		BigDecimal generatingBalance = rs.getBigDecimal(8);
+			long timestamp = rs.getTimestamp(7).getTime();
-		byte[] generatorPublicKey = DB.getResultSetBytes(rs.getBinaryStream(9));
+			BigDecimal generatingBalance = rs.getBigDecimal(8);
-		byte[] generatorSignature = DB.getResultSetBytes(rs.getBinaryStream(10), GENERATOR_SIGNATURE_LENGTH);
+			byte[] generatorPublicKey = DB.getResultSetBytes(rs.getBinaryStream(9));
-		byte[] atBytes = DB.getResultSetBytes(rs.getBinaryStream(11));
+			byte[] generatorSignature = DB.getResultSetBytes(rs.getBinaryStream(10));
-		BigDecimal atFees = rs.getBigDecimal(12);
+			byte[] atBytes = DB.getResultSetBytes(rs.getBinaryStream(11));
-
+			BigDecimal atFees = rs.getBigDecimal(12);
-		return new Block(version, reference, transactionCount, totalFees, transactionsSignature, height, timestamp,
+	
-				generatingBalance,generatorPublicKey, generatorSignature, atBytes, atFees);
+			return new Block(version, reference, transactionCount, totalFees, transactionsSignature, height, timestamp,
+					generatingBalance,generatorPublicKey, generatorSignature, atBytes, atFees);
+		}
+		catch(SQLException e)
+		{
+			throw new DataException("Error extracting data from result set", e);
+		}
 	}
 }

src/repository/hsqldb/HSQLDBGenesisTransactionRepository.java

@@ -12,9 +12,13 @@ import database.DB;
 
 public class HSQLDBGenesisTransactionRepository extends HSQLDBTransactionRepository {
 
+	public HSQLDBGenesisTransactionRepository(HSQLDBRepository repository) {
+		super(repository);
+	}
+
 	Transaction fromBase(byte[] signature, byte[] reference, PublicKeyAccount creator, long timestamp, BigDecimal fee) {
 		try {
-			ResultSet rs = DB.checkedExecute("SELECT recipient, amount FROM GenesisTransactions WHERE signature = ?", signature);
+			ResultSet rs = DB.checkedExecute(repository.connection, "SELECT recipient, amount FROM GenesisTransactions WHERE signature = ?", signature);
 			if (rs == null)
 				return null;
 

src/repository/hsqldb/HSQLDBRepository.java

@@ -1,11 +1,65 @@
 package repository.hsqldb;
 
+import java.lang.ref.PhantomReference;
+import java.lang.ref.ReferenceQueue;
+import java.sql.Connection;
+import java.sql.SQLException;
+
+import database.DB;
+import repository.DataException;
 import repository.Repository;
 
 public class HSQLDBRepository extends Repository {
 
-	public HSQLDBRepository() {
+	Connection connection;
-		this.transactionRepository = new HSQLDBTransactionRepository();
+	
+	public HSQLDBRepository()  throws DataException {
+		try {
+			initialize();
+		} catch (SQLException e) {
+			throw new DataException("initialization error", e);
+		}
+		
+		this.transactionRepository = new HSQLDBTransactionRepository(this);
+	}
+
+	private void initialize() throws SQLException {
+		connection = DB.getPoolConnection();
+		
+		// start transaction
+		connection.setTransactionIsolation(Connection.TRANSACTION_SERIALIZABLE);
+		connection.setAutoCommit(false);
+	}
+
+	@Override
+	public void saveChanges() throws DataException {
+		try {
+			connection.commit();
+		} catch (SQLException e) {
+			throw new DataException("commit error", e);
+		}		
+	}
+
+	@Override
+	public void discardChanges() throws DataException {
+		try {
+			connection.rollback();
+		} catch (SQLException e) {
+			throw new DataException("rollback error", e);
+		}		
+	}
+
+	// TODO prevent leaking of connections if .close() is not called before garbage collection of the repository.
+	// Maybe use PhantomReference to call .close() on connection after repository destruction?
+	@Override
+	public void close() throws DataException {
+		try {
+			// give connection back to the pool
+			connection.close();
+			connection = null;
+		} catch (SQLException e) {
+			throw new DataException("close error", e);
+		}		
 	}
 
 }

src/repository/hsqldb/HSQLDBSaver.java

@@ -1,6 +1,7 @@
 package repository.hsqldb;
 
 import java.math.BigDecimal;
+import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.SQLException;
 import java.util.ArrayList;
@@ -55,9 +56,13 @@ public class HSQLDBSaver {
 	 * @throws SQLException
 	 */
 	public boolean execute() throws SQLException {
-		String sql = this.formatInsertWithPlaceholders();
+		Connection connection = DB.getConnection();
+		return execute(connection);
+	}
 
-		PreparedStatement preparedStatement = DB.getConnection().prepareStatement(sql);
+	public boolean execute(Connection connection) throws SQLException {
+		String sql = this.formatInsertWithPlaceholders();
+		PreparedStatement preparedStatement = connection.prepareStatement(sql);
 
 		this.bindValues(preparedStatement);
 

src/repository/hsqldb/HSQLDBTransactionRepository.java

@@ -1,6 +1,7 @@
 package repository.hsqldb;
 
 import java.math.BigDecimal;
+import java.sql.Connection;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.sql.Timestamp;
@@ -14,15 +15,17 @@ import repository.TransactionRepository;
 
 public class HSQLDBTransactionRepository implements TransactionRepository {
 
+	protected HSQLDBRepository repository;
 	private HSQLDBGenesisTransactionRepository genesisTransactionRepository;
 
-	public HSQLDBTransactionRepository() {
+	public HSQLDBTransactionRepository(HSQLDBRepository repository) {
-		genesisTransactionRepository = new HSQLDBGenesisTransactionRepository();
+		this.repository = repository;
+		genesisTransactionRepository = new HSQLDBGenesisTransactionRepository(repository);
 	}
 
 	public Transaction fromSignature(byte[] signature) {
 		try {
-			ResultSet rs = DB.checkedExecute("SELECT type, reference, creator, creation, fee FROM Transactions WHERE signature = ?", signature);
+			ResultSet rs = DB.checkedExecute(repository.connection, "SELECT type, reference, creator, creation, fee FROM Transactions WHERE signature = ?", signature);
 			if (rs == null)
 				return null;
 
@@ -40,7 +43,7 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 
 	public Transaction fromReference(byte[] reference) {
 		try {
-			ResultSet rs = DB.checkedExecute("SELECT type, signature, creator, creation, fee FROM Transactions WHERE reference = ?", reference);
+			ResultSet rs = DB.checkedExecute(repository.connection, "SELECT type, signature, creator, creation, fee FROM Transactions WHERE reference = ?", reference);
 			if (rs == null)
 				return null;
 
@@ -74,7 +77,7 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 
 		// in one go?
 		try {
-			ResultSet rs = DB.checkedExecute("SELECT height from BlockTransactions JOIN Blocks ON Blocks.signature = BlockTransactions.block_signature WHERE transaction_signature = ? LIMIT 1", signature);
+			ResultSet rs = DB.checkedExecute(repository.connection, "SELECT height from BlockTransactions JOIN Blocks ON Blocks.signature = BlockTransactions.block_signature WHERE transaction_signature = ? LIMIT 1", signature);
 			if (rs == null)
 				return 0;
 			
@@ -92,7 +95,7 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 
 		// Fetch block signature (if any)
 		try {
-			ResultSet rs = DB.checkedExecute("SELECT block_signature from BlockTransactions WHERE transaction_signature = ? LIMIT 1", signature);
+			ResultSet rs = DB.checkedExecute(repository.connection, "SELECT block_signature from BlockTransactions WHERE transaction_signature = ? LIMIT 1", signature);
 			if (rs == null)
 				return null;
 			
@@ -114,7 +117,7 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 				.bind("creator", transaction.getCreator().getPublicKey()).bind("creation", new Timestamp(transaction.getTimestamp())).bind("fee", transaction.getFee())
 				.bind("milestone_block", null);
 		try {
-			saver.execute();
+			saver.execute(repository.connection);
 		} catch (SQLException e) {
 			// XXX do what?
 		}
@@ -125,7 +128,7 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 		// NOTE: The corresponding row in sub-table is deleted automatically by the database thanks to "ON DELETE CASCADE" in the sub-table's FOREIGN KEY
 		// definition.
 		try {
-			DB.checkedExecute("DELETE FROM Transactions WHERE signature = ?", transaction.getSignature());
+			DB.checkedExecute(repository.connection, "DELETE FROM Transactions WHERE signature = ?", transaction.getSignature());
 		} catch (SQLException e) {
 			// XXX do what?
 		}