--- a/src/main/java/org/monetdb/jdbc/MonetConnection.java
+++ b/src/main/java/org/monetdb/jdbc/MonetConnection.java
@@ -92,7 +92,7 @@ public class MonetConnection
 	private final BufferedMCLWriter out;
 
 	/** A StartOfHeaderParser declared for reuse. */
-	private StartOfHeaderParser sohp = new StartOfHeaderParser();
+	private final StartOfHeaderParser sohp = new StartOfHeaderParser();
 
 	/** Whether this Connection is closed (and cannot be used anymore) */
 	private boolean closed;
@@ -115,7 +115,7 @@ public class MonetConnection
 	// See javadoc for documentation about WeakHashMap if you don't know what
 	// it does !!!NOW!!! (only when you deal with it of course)
 	/** A Map containing all (active) Statements created from this Connection */
-	private WeakHashMap<Statement,?> statements = new WeakHashMap<Statement, Object>();
+	private final WeakHashMap<Statement,?> statements = new WeakHashMap<Statement, Object>();
 
 	/** The number of results we receive from the server at once */
 	private int curReplySize = -1;	// the server by default uses -1 (all)
@@ -137,9 +137,9 @@ public class MonetConnection
 	private final int lang;
 
 	/** Whether or not BLOB is mapped to Types.VARBINARY instead of Types.BLOB within this connection */
-	private boolean treatBlobAsVarBinary = true;
+	private boolean treatBlobAsVarBinary = true;	// turned on by default for optimal performance (from JDBC Driver release 2.30 onwards)
 	/** Whether or not CLOB is mapped to Types.VARCHAR instead of Types.CLOB within this connection */
-	private boolean treatClobAsVarChar = true;
+	private boolean treatClobAsVarChar = true;	// turned on by default for optimal performance (from JDBC Driver release 2.30 onwards)
 
 	/** The last set query timeout on the server as used by Statement, PreparedStatement and CallableStatement */
 	protected int lastSetQueryTimeout;	// 0 means no timeout, which is the default on the server
@@ -885,7 +885,7 @@ public class MonetConnection
 	 * @param sql - an SQL statement that may contain one or more '?' IN parameter placeholders
 	 * @param columnIndexes - an array of column indexes indicating the columns that should be returned from the inserted row or rows
 	 * @return a new PreparedStatement object, containing the pre-compiled statement, that is capable of
-	 * 	returning the auto-generated keys designated by the given array of column indexes
+	 *	returning the auto-generated keys designated by the given array of column indexes
 	 * @throws SQLException - if a database access error occurs or this method is called on a closed connection
 	 * @throws SQLFeatureNotSupportedException - if the JDBC driver does not support this method
 	 */
@@ -914,7 +914,7 @@ public class MonetConnection
 	 * @param sql - an SQL statement that may contain one or more '?' IN parameter placeholders
 	 * @param columnNames - an array of column names indicating the columns that should be returned from the inserted row or rows
 	 * @return a new PreparedStatement object, containing the pre-compiled statement, that is capable of
-	 * 	returning the auto-generated keys designated by the given array of column names
+	 *	returning the auto-generated keys designated by the given array of column names
 	 * @throws SQLException - if a database access error occurs or this method is called on a closed connection
 	 * @throws SQLFeatureNotSupportedException - if the JDBC driver does not support this method
 	 */
@@ -1326,7 +1326,7 @@ public class MonetConnection
 			if (timeout > 0 && original_timeout != this.lastSetQueryTimeout) {
 				this.lastSetQueryTimeout = original_timeout;
 				try {
-					/* we have to set in the server explicitly, because the test 'queryTimeout != connection.lastSetQueryTimeout' 
+					/* we have to set in the server explicitly, because the test 'queryTimeout != connection.lastSetQueryTimeout'
 					   on MonetStatement.internalExecute(sql) won't pass and the server won't be set back */
 					setQueryTimeout(original_timeout);
 				} catch (SQLException se) {

--- a/src/main/java/org/monetdb/jdbc/MonetDataSource.java
+++ b/src/main/java/org/monetdb/jdbc/MonetDataSource.java
@@ -34,7 +34,7 @@ public final class MonetDataSource
 	implements DataSource
 {
 	private String description;
-	private int loginTimeout = 0;
+	private int loginTimeout;
 	private String user;
 	// insecure, but how to do it better?
 	private String password;

--- a/src/main/java/org/monetdb/jdbc/MonetDriver.java.in
+++ b/src/main/java/org/monetdb/jdbc/MonetDriver.java.in
@@ -392,7 +392,7 @@ public class MonetDriver implements Driv
 	 *               in the SQL CASE statement
 	 * @return a SQL CASE statement
 	 */
-	private static String TypeMapppingSQL = null;	// cache to optimise getSQLTypeMap()
+	private static String TypeMapppingSQL;	// cache to optimise getSQLTypeMap()
 	static final String getSQLTypeMap(final String column) {
 		if (TypeMapppingSQL == null) {
 			// first time, compose TypeMappping SQL string

--- a/src/main/java/org/monetdb/jdbc/MonetResultSet.java
+++ b/src/main/java/org/monetdb/jdbc/MonetResultSet.java
@@ -90,7 +90,7 @@ public class MonetResultSet
 	/** The number of rows in this ResultSet */
 	protected final long tupleCount;
 	/** The current position of the cursor for this ResultSet object */
-	protected int curRow = 0;
+	protected int curRow;
 
 	/** The type of this ResultSet (forward or scrollable) */
 	private int type = DEF_RESULTSETTYPE;

--- a/src/main/java/org/monetdb/jdbc/MonetStatement.java
+++ b/src/main/java/org/monetdb/jdbc/MonetStatement.java
@@ -1506,7 +1506,7 @@ public class MonetStatement
  * TODO: try to eliminate the need for this class completely.
  */
 final class MonetVirtualResultSet extends MonetResultSet {
-	private String results[][];
+	private final String results[][];
 	private boolean closed;
 
 	MonetVirtualResultSet(
@@ -1570,7 +1570,6 @@ final class MonetVirtualResultSet extend
 	public void close() {
 		if (!closed) {
 			closed = true;
-			results = null;
 			// types and columns are MonetResultSets private parts
 		}
 	}