Table of Contents
Changes and fixes in Jaybird 2.2.7
Changes and fixes in Jaybird 2.2.6
Changes and fixes in Jaybird 2.2.5
Changes and fixes in Jaybird 2.2.4
Changes and fixes in Jaybird 2.2.3
Changes and fixes in Jaybird 2.2.2
Changes and fixes in Jaybird 2.2.1
Changes and fixes since Jaybird 2.2.0 beta 1
Support for getGeneratedKeys()
Java 6 and JDBC 4.0 API support
Java 7 and JDBC 4.1 API support
Java 8 and JDBC 4.2 API support
Native and Embedded (JNI) 64-bit Windows and Linux support
Improved support for OpenOffice / LibreOffice Base
Important changes to Datasources
Where to get more information on Jaybird
Corrections/Additions To Release Notes
Using Type 2 and Embedded Server driver
Configuring Type 2 JDBC driver
Configuring Embedded Server JDBC driver
Support for multiple JNI libraries
Firebird management interfaces
JDBC deviations and unimplemented features
Using java.sql.ParameterMetaData with Callable Statements
Using ResultSet.getCharacterStream with BLOB fields
Heuristic transaction completion support
Compatibility with com.sun.rowset.*
Support for Firebird 3 BOOLEAN type
Connection pooling with Jaybird
Description of deprecated org.firebirdsql.pool classes
Connection Pool Classes (deprecated)
org.firebirdsql.pool.FBConnectionPoolDataSource (deprecated)
Jaybird is a JCA/JDBC driver suite to connect to Firebird database servers.
This driver is based on both the JCA standard for application server connections to enterprise information systems and the well-known JDBC standard.
The JCA standard specifies an architecture in
which an application server can cooperate with a driver so that the
application server manages transactions, security, and resource
pooling, and the driver supplies only the connection functionality.
While similar to the JDBC XADataSource
concept, the JCA specification is considerably clearer on the
division of responsibility between the application server and driver.
Jaybird 2.2.7 was tested against Firebird 2.1.7, Firebird 2.5.3 Update 1 and Firebird 3 beta 1, but should also support other Firebird versions from 1.0 and up. The Type 2 and embedded server JDBC drivers require the appropriate JNI library. Precompiled JNI binaries for Win32 and Linux platforms are shipped in the default installation, other platforms require porting/building the JNI library for that platform.
Connecting to Firebird 3 requires some additional configuration, see Jaybird and Firebird 3.0 Beta 1 for details.
This driver does not support InterBase servers due to Firebird-specific changes in the protocol and database attachment parameters that are sent to the server.
Jaybird 2.2.7 supports Java 5 (JDBC 3.0), Java 6 (JDBC 4.0), Java 7 (JDBC 4.1) and Java 8 (JDBC 4.2). Support for earlier Java versions has been dropped.
Driver supports the following specifications:
JDBC 4.2 |
Driver does not fully support JDBC 4.2 features, but implements large update count methods by calling the normal update count methods, and methods with SQLType by calling methods accepting the java.sql.Types integer value. Supports new java.Time classes with some caveats. |
JDBC 4.1 |
Driver implements all JDBC 4.1 methods added to existing interfaces. The driver explicitly supports closeOnCompletion, most other methods introduced with JDBC 4.1 throw SQLFeatureNotSupportedException. |
JDBC 4.0 |
Driver implements all JDBC 4.0 interfaces and supports exception chaining. |
JDBC 3.0 |
Driver implements all JDBC 3.0 interfaces (but will throw FBDriverNotCapableException for some methods) |
JCA 1.0 |
Jaybird provides implementation of
Although Jaybird depends on the JCA 1.5 classes, JCA 1.5 compatibility is currently not guaranteed. |
JTA 1.0.1 |
Driver provides an implementation of
|
JMX 1.2 |
Jaybird provides a MBean to manage Firebird servers and installed databases via JMX agent. |
Jaybird 2.2 introduces the following new features and fixes:
The following has been changed or fixed in Jaybird 2.2.7:
Fixed: blob return value of executable
procedure obtained through getters on CallableStatement
is 8 byte blob id, instead of expected blob content (JDBC-381)
This
was a regression caused by the changes of JDBC-350.
The following are known in issues in Jaybird 2.2.7 (and earlier):
ResultSets opened with CLOSE_CURSORS_AT_COMMIT aren't correctly closed on commit when auto-commit is off (JDBC-307)
This list is not exhaustive, see the Jaybird tracker for a full list of open bugs.
The following has been changed or fixed in Jaybird 2.2.6:
Reverted Firebird 3 workaround for updatable result sets as bug has been fixed in Firebird (JDBC-330)
Fixed: Processing and closing the ResultSet
from callable statement and then using the getters throws
NullPointerException
(JDBC-350)
Using
both the getters and the result set for the same callable statement
is incorrect; the ability to do this might be removed in a future
version of Jaybird. A ResultSet
should be used for selectable procedures, while the getters should
be used with executable procedures.
Fixed: FBManagedConnectionFactory.tryCompleteInLimboTransaction doesn't work with recent Firebird 3 builds (JDBC-353)
Fixed: Jaybird can throw a NullPointerException when a fatal connection error has occurred (JDBC-359)
Fixed: Calling close on a JCA connection triggers exception Connection enlisted in distributed transaction (JDBC-362)
Fixed: Potential memory-leak when using a lot of different connection strings and/or properties (JDBC-364)
Fixed: FBRowUpdater.buildInsertStatement doesn't quote column names (JDBC-370)
Fixed: EncodingFactory doesn't handle UnsupportedCharsetException (JDBC-371)
Fixed: Current method of quoting in FBRowUpdater incorrect for dialect 1 (JDBC-372)
The following has been changed or fixed in Jaybird 2.2.5:
Fixed: getCrossReference broken by changes of JDBC-331 (JDBC-335)
Added:
basic support for Java 8 java.time
in
PreparedStatement.setObject()
and
ResultSet.updateObject()
(JDBC-339)
As
part of this change the supported sub-second precision for
java.sql.Timestamp
has been increased from 1
millisecond to the maximum Firebird precision of 100 microseconds
(or 0.1 millisecond)1.
Fixed: Deadlocks and other thread safety issues with classes in org.firebirdsql.pool (JDBC-341)
The following has been changed or fixed in Jaybird 2.2.4:
Fixed: Exceptions during statement preparation leave connection and transaction open after explicit close (JDBC-311)
Fixed batch update (or insert) with blob set through setBinaryStream() sets empty blob for all but the first batch entry (JDBC-312)
Fixed incomplete checks of database, transaction, statement and blob handle validity before continuing with actions. These incomplete checks could lead to unexpected exceptions (for example a NullPointerException in iscDatabaseInfo) (JDBC-313)
Fixed error when setting connection charset equal to "file.encoding" java property (JDBC-314)
Fixed connection character set not correctly set when specifying the Java connection characterset (charSet or localEncoding property) (JDBC-315)
Fixed incorrect lengths and/or radix reported by getTypeInfo and getColumns metadata (JDBC-317, JDBC-318)
Initial Java 8 / JDBC 4.2 support (JDBC-319)
Firebird 3 BOOLEAN type support, see Support for Firebird 3 BOOLEAN type (JDBC-321)
Added fallback of loading GDSFactoryPlugin implementations to prevent NullPointerException in Hibernate reverse engineering wizard in NetBeans (JDBC-325)
Fixed: Jaybird should specify dialect 3 in dpb when no explicit dialect was set (JDBC-327)
Fixed:
several DatabaseMetaData
methods defined by JDBC to only accept the actual table name also
accepted a LIKE-pattern
or empty string or null.
This was changed to conform to JDBC. This change can break
applications that relied on the
incorrect behavior (JDBC-331)
Affected
methods are: getPrimaryKeys,
getBestRowIdentifier,
getImportedKeys,
getExportedKeys
and
getCrossReference.
As part of this change
getIndexInfo
now handles names in the wrong case slightly different.
Jaybird
3.0 will further modify and restrict the pattern matching and case
sensitivity of metadata methods. See Future changes to Jaybird.
The following has been changed or fixed in Jaybird 2.2.3:
Fixed incorrect synchronization in native
and embedded protocol (JNI) implementation for iscBlobInfo
and iscSeekBlob
(JDBC-300)
WARNING:
Although Jaybird strives for correct synchronization, a JDBC
Connection,
and its dependent objects should be used from a single Thread
at a time, sharing
on multiple threads concurrently is not advisable.
Fixed holdable ResultSet is closed on auto-commit (JDBC-304, JDBC-305)
Fixed table names missing or padded with spaces in Database view of IntelliJ IDEA (JDBC-308, IDEA-100786)
Fixed incorrect JDBC minor version reported under Java 7; this resulted in an incorrect column name (for Java 7) in the metadata of DatabaseMetaData.getColumns(...) (JDBC-309)
Added IOException to cause of GDSException with error 335544721; “Unable to complete network request to host “”” for further investigation (JDBC-306)
The following has been changed or fixed in Jaybird 2.2.2:
Fixed: FBMaintenanceManager.listLimboTransactions() reports incorrect transaction id when the result contains multi-site transactions in limbo (JDBC-266)
Fixed: Calling PreparedStatement.setClob(int, Clob) with a non-Firebird Clob (eg like Hibernate does) or calling PreparedStatement.setClob(int, Reader) throws FBSQLException: “You can't start before the beginning of the blob” (JDBC-281)
Fixed: Connection property types not properly processed from isc_dpb_types.properties (JDBC-284)
Fixed: JNI implementation of parameter buffer writes incorrect integers (JDBC-285, JDBC-286)
Changed: Throw SQLException
when calling execute,
executeQuery,
executeUpdate
and addBatch
methods accepting a query string on a PreparedStatement
or CallableStatement
as required by JDBC 4.0 (JDBC-288)
NOTE:
Be aware that this change can break existing code if you depended on
the old, non-standard behavior! With addBatch(String)
the old behavior lead to a memory leak and unexpected results.
Fixed: LIKE escape character JDBC escape ({escape '<char>'}) doesn't work (JDBC-290)
Added: Support for a connect timeout using
connection property connectTimeout.
This property can be specified in the JDBC URL or Properties
object or on the DataSource.
If the connectTimeout
property is not specified, the general DriverManager
property loginTimeout
is used. The value is the timeout in seconds. (JDBC-295)
For
the Java wire protocol the connect timeout will detect unreachable
hosts. In the JNI implementation (native protocol) the connect
timeout works as the DPB item isc_dpb_connect_timeout
which only works after connecting to the server for the op_accept
phase of the protocol. This means that – for the native
protocol – the connect timeout will not detect unreachable
hosts within the timeout. As that might be unexpected, an SQLWarning
is added to the connection if the property is specified with the
native protocol.
As part of the connect timeout change, hostname handling (if the hostname is an IP-address) in the Java wire protocol was changed. This should not have an impact in recent Java versions, but on older Java versions (Java 5 up to update 5) this might result in a delay in connecting using an IP-address, if that address can't be reverse-resolved to a hostname. Workaround is to add an entry for that IP-address to the /etc/hosts or %WINDIR%\System32\Drivers\etc\hosts file.
The following has been changed or fixed in Jaybird 2.2.1:
Fixed: UnsatisfiedLinkError in libjaybird22(_x64).so undefined symbol: _ZTVN10__cxxabiv117__class_type_infoE on Linux (JDBC-259)
Added
connection property columnLabelForName
for backwards compatible behavior of
ResultSetMetaData#getColumnName(int)
and compatibility with bug in com.sun.rowset.CachedRowSetImpl
(JDBC-260)
Set
property to true
for backwards compatible behavior (getColumnName()
returns the column label); don't set the property or set it
to false
for JDBC-compliant behavior (recommended).
Fixed: setString(column, null) on “? IS (NOT) NULL” condition does not set parameter to NULL (JDBC-264)
The charSet connection property now accepts all aliases of the supported Java character sets (eg instead of only Cp1252 now windows-1252 is also accepted) (JDBC-267)
Fixed: values of charSet property are case-sensitive (JDBC-268)
Fixed: setting a parameter as NULL with the native protocol does not work when Firebird describes the parameter as not nullable (JDBC-271)
The following was changed or fixed after the release of Jaybird 2.2.0 beta 1:
ConcurrentModificationException when closing connection obtained from org.firebirdsql.ds.FBConnectionPoolDataSource with statements open (JDBC-250)
Memory leak when obtaining multiple connections for the same URL (JDBC-249)
CPU spikes to 100% when using events and Firebird Server is stopped or unreachable (JDBC-232)
Events do not work on Embedded (JDBC-247)
Provide workaround for character set transliteration problems in database filenames and other connection properties (JDBC-253); see also Support for Firebird 2.5.
FBBackupManager does not allow 16kb page size for restore (JDBC-255)
Log warning and add warning on Connection when no explicit connection character set is specified (JDBC-257)
Support was added for the getGeneratedKeys() functionality for Statement and PreparedStatement.
There are four distinct use-cases:
Methods accepting an int parameter with values of Statement.NO_GENERATED_KEYS and Statement.RETURN_GENERATED_KEYS
When NO_GENERATED_KEYS is passed, the query will be executed as a normal query.
When RETURN_GENERATED_KEYS is passed, the driver will add all columns of the table in ordinal position order (as in the (JDBC) metadata of the table). It is advisable to retrieve the values from the getGeneratedKeys() resultset by column name.
We opted to include all columns as it is next to impossible to decide which columns are filled by a trigger or otherwise and only returning the primary key will be too limiting
Methods accepting an int[] parameter with column indexes.
The values in the int[] parameter are the ordinal positions of the columns as specified in the (JDBC) metadata of the table. For a null or empty array the statement is processed as is. Invalid ordinal positions are ignored and silently dropped (be aware: the JDBC specification is not entirely clear if this is valid behavior, so this might change in the future)
Methods accepting a String[] parameter with column names.
The values in the String[] are the column names to be returned. The column names provided are processed as is and not checked for validity or the need of quoting. Providing non-existent or incorrectly (un)quoted columns will result in an exception when the statement is processed by Firebird.
This method is the fastest as it does not retrieve metadata from the server.
Providing a query already containing a RETURNING clause. In this case all of the previous cases are ignored and the query is executed as is. It is possible to retrieve the resultset using getGeneratedKeys().
This functionality will only be available if the ANTLR 3.4 runtime classes are on the classpath. Except for calling methods with NO_GENERATED_KEYS, absence of the ANTLR runtime will throw FBDriverNotCapableException.
This functionality should work for INSERT (from Firebird 2.0), and for UPDATE, UPDATE OR INSERT and DELETE (from Firebird 2.1).
Support was added for the following JDBC 4.0 features:
Automatic driver loading: on Java 6 and later it is no longer necessary to use Class.forName("org.firebirdsql.jdbc.FBDriver") to load the driver
Implementation of java.sql.Wrapper interface on various JDBC classes; in general it only unwraps to the specific implementation class (and superclasses) and implemented interfaces
Support for chained exceptions (use getNextException() and iterator() to view other, related exceptions) and getCause() to retrieve the cause (deprecating similar getInternalException())
Support for getClientInfo() and setClientInfo() on Connection
Support was added for the following JDBC 4.1 features:
try-with-resources2
Statement closeOnCompletion
Other methods added by JDBC 4.1 will throw FBDriverNotCapableException (a subclass of SQLFeatureNotSupportedException).
Minimal support for JDBC 4.2 was added in Jaybird 2.2.4 and extended in 2.2.5:
Large update counts: no actual support is provided, method call is forwarded to the normal update count method returning an int.
Methods accepting java.sql.SQLType: no actual support is provided, method call is forwarded to equivalent method accepting a java.sql.Types integer value.
PreparedStatement.setObject() and ResultSet.updateObject() now accept java.time objects:
|
DATE |
TIME |
TIMESTAMP |
(VAR)CHAR |
BLOB SUB_TYPE TEXT |
---|---|---|---|---|---|
java.time.LocalTime |
|
X |
|
X |
X |
java.time.LocalDate |
X |
|
|
X |
X |
java.time.LocalDateTime |
X |
X |
X |
X |
X |
java.time.OffsetTime |
|
|
|
X |
X |
java.time.OffsetDateTime |
|
|
|
X |
X |
Retrieval of java.time objects using getObject(int, Class<?>) and getObject(String, Class<?>) is not yet supported.
Jaybird 2.2.7 is available on maven, with a separate artifact for each supported Java version.
Groupid: org.firebirdsql.jdbc, artifactid: jaybird-jdkXX (where XX is 15, 16, 17 or 18).
Version: 2.2.7
When deploying to a JavaEE environment, exclude the javax.resource connector-api dependency as this will be provided by the application server.
The JNI libraries for native and embedded support now also have a 64 bit version.
Added support for Firebird 2.5 Services API enhancements:
The security database can be set
Support for SET/DROP AUTO ADMIN
Mapping for new role RDB$ADMIN in security database
Added new Firebird 2.1 shutdown/online modes available in Firebird 2.5 via the Services API
Support for NBackup via Services API in Firebird 2.5
Support for Trace/Audit via Services API in Firebird 2.5
Since Firebird 2.5, Firebird supports full UTF-8 database filenames and other connection properties (Database Parameter Buffer values). Jaybird does not yet support these changes, but a workaround is available:
This workaround consists of two steps
Ensure your Java application is executed with the system property file.encoding=UTF-8 (either because that is the default encoding for your OS, or by explicitly specifying this property on the commandline of your application using -Dfile.encoding=UTF-8)
Include property utf8_filename=1 in the JDBC URL or (non-standard) properties of the datasource
This will only work if the Firebird server is version 2.5 or higher.
Jaybird 2.2.x only supports Firebird 3.0 using the legacy authentication. The new authentication model and wire protocol encryption is not yet supported. Technically these new protocol options will work when using the Type 2 driver, but this hasn't been fully tested.
When using Jaybird with Firebird 3.0, make sure that
Wire protocol encryption is not required
Legacy authentication is enabled
The user has been created with the legacy usermanager
The new BOOLEAN data type is supported
See the Jaybird Wiki for more details.
The interpretation of the JDBC standard by Jaybird differs from the interpretation by OpenOffice / LibreOffice. To address some of the problems caused by these differences, Jaybird now provides a separate protocol for OpenOffice / LibreOffice.
When connecting from Base, use the protocol prefix jdbc:firebirdsql:oo:. Be aware that this is a variant of the pure Java wire protocol and not the native or embedded protocol.
Issues addressed by this protocol:
Result sets are not closed when a statements is finished (eg fully read ResultSet or when creating a new Statement in auto-commit mode)
DatabaseMetaData#getTablePrivileges(...) reports privileges granted to PUBLIC and to the current role (as reported by CURRENT_ROLE) as being granted to the user (after Jaybird 2.2.0 beta 1).
Replaced mini-j2ee.jar with connector-api-1.5.jar: make sure to remove the old mini-j2ee.jar from the classpath of your application.
Dropped jaybird-pool jar from the distribution (all classes are include in the jaybird jar and the jaybird-full jar)
FBResultSetMetaData#getcolumnName(int)
will now return the original column name (if available) for
compliance with the JDBC specification, getColumnLabel(int)
will still return the alias (or the column name if no alias is
defined). See Compatibility with com.sun.rowset.* for potential
problems when using the reference implementation of
CachedRowSet.
Jaybird
2.2.1 introduced the connection property columnLabelForName
which will revert to the old behavior when set to true.
Be aware that the old behavior is not JDBC-compliant.
FBDatabaseMetaData has been updated to include metadata columns defined by JDBC 3.0, 4.0 and 4.1. This also changes the position of OWNER_NAME column in the result set of getTables(..) as this column is Jaybird-specific and not defined in JDBC.
FBDatabaseMetaData#getIndexInfo(..) now also returns expression indexes. The COLUMN_NAME column will contain the expression (if available).
FBDatabaseMetaData#getIndexInfo(..) now correctly limits the returned indexes to unique indexes when parameter unique is set to true.
The connection property octetsAsBytes can be used to identify fields with CHARACTER SET OCTETS as being (VAR)BINARY (in ResultSetMetaData only)
The getTime(), getDate(), getTimestamp() methods which take a Calendar object now correctly handle conversions around Daylight Savings Time (DST) changes. Before, the time was first converted to the local JVM timezone, and then to the timezone of the provided Calendar, this could lose up to an hour in time. Now the time is converted directly to the timezone of the provided Calendar. (JDBC-154)
A full list of changes is available at:
Jaybird 2.2.7: http://tracker.firebirdsql.org/secure/ReleaseNote.jspa?version=10660&styleName=Text&projectId=10002
Jaybird 2.2.6: http://tracker.firebirdsql.org/secure/ReleaseNote.jspa?version=10588&styleName=Text&projectId=10002
Jaybird 2.2.5: http://tracker.firebirdsql.org/secure/ReleaseNote.jspa?version=10582&styleName=Text&projectId=10002
Jaybird 2.2.4: http://tracker.firebirdsql.org/secure/ReleaseNote.jspa?version=10531&styleName=Text&projectId=10002
Jaybird 2.2.3: http://tracker.firebirdsql.org/secure/ReleaseNote.jspa?version=10510&styleName=Text&projectId=10002
Jaybird 2.2.2: http://tracker.firebirdsql.org/secure/ReleaseNote.jspa?projectId=10002&styleName=Text&version=10480
Jaybird 2.2.1: http://tracker.firebirdsql.org/secure/ReleaseNote.jspa?version=10474&styleName=Text&projectId=10002
Jaybird 2.2.0: http://tracker.firebirdsql.org/secure/ReleaseNote.jspa?version=10053&styleName=Text&projectId=10002
Jaybird 2.2 introduces some changes in compatibility and announces future breaking changes. The version previously announced as Jaybird 2.3 will be released as Jaybird 3.0.
Java 5 support will be dropped for Jaybird 3.0 as Java 5 has been on End-Of-Public-Updates3 status since October 2009.
Java 6 support will be dropped for Jaybird 3.1 as Java 6 has been on End-Of-Public-Updates status since February 2013.
Jaybird 2.2 supports Firebird 1.0 and higher, but is only tested with Firebird 2.1, 2.5 and 3.0. With Jaybird 3.0 formal support for Firebird 1.0 and 1.5 will be dropped. In general this should not impact the use of the driver, but might have impact on the availability and use of metadata information. This also means that from Jaybird 3.0 bugs that only occur with Firebird 1.0 and 1.5 will not be fixed. With Jaybird 3.1 support for Firebird 2.0 will be dropped.
The ConnectionPoolDataSource and XADataSource implementations in org.firebirdsql.pool and org.firebirdsql.pool.sun contain several bugs with regard to pool and connection management when used by a JavaEE application server. The decision was made to write new implementations in the package org.firebirdsql.ds.
The following implementation classes have been deprecated and will be removed in Jaybird 3.0:
org.firebirdsql.pool.DriverConnectionPoolDataSource
org.firebirdsql.pool.FBConnectionPoolDataSource
org.firebirdsql.pool.sun.AppServerDataSource
org.firebirdsql.pool.sun.AppServerXADataSource
org.firebirdsql.jca.FBXADataSource
org.firebirdsql.pool.SimpleDataSource
Their replacement classes are:
org.firebirdsql.ds.FBConnectionPoolDataSource
org.firebirdsql.ds.FBXADataSource
org.firebirdsql.pool.FBSimpleDataSource (a normal DataSource)
We strongly urge you to switch to these new implementations if you are using these classes in an application server. The bugs are described in JDBC-86, JDBC-93, JDBC-131 and JDBC-144.
The deprecated classes can still be used with the DataSource implementations WrappingDataSource as the identified bugs do not occur with this implementation, but we advise you to switch to FBSimpleDataSource. If you require a standalone connection pool (outside an application server) or statement pooling, please consider using a third-party connection pool like C3P0, DBCP or HikariCP.
The new ConnectionPoolDataSource and XADataSource implementations only provide the basic functionality specified in the JDBC specifications and do not provide any pooling itself. The ConnectionPoolDataSource and XADataSource are intended to be used by connection pools (as provided by application servers) and should not be connection pools themselves.
The next versions of Jaybird will include some – potentially – breaking changes. We advise to check your code if you will be affected by these changes and prepare for these changes if possible.
As announced above, the ConnectionPoolDataSource implementations in org.firebirdsql.pool and org.firebirdsql.jca will be removed in Jaybird 3.0. The entire org.firebirdsql.pool package will be removed.
The following (deprecated) classes will also be removed:
org.firebirdsql.jdbc.FBWrappingDataSource (old deprecated class subclassing org.firebirdsql.pool.FBWrappingDataSource), only included in jaybird-full jar
Furthermore the following interfaces will be removed as they are no longer needed:
FirebirdSavepoint (identical to java.sql.Savepoint)
The following interfaces will have some of the methods removed:
FirebirdConnection
setFirebirdSavepoint() replace with Connection#setSavepoint()
setFirebirdSavepoint(String name) replace with Connection#setSavepoint(String name)
rollback(FirebirdSavepoint savepoint) replace with Connection#rollback(Savepoint savepoint)
releaseSavepoint(FirebirdSavepoint savepoint) replace with Connection#releaseSavepoint(Savepoint savepoint)
If you are still using these interfaces or methods, please change your code to use the JDBC interface or method instead.
From Jaybird 3.0 on (VAR)CHAR CHARACTER SET OCTETS will be considered to be of java.sql.Types type (VAR)BINARY. This should not impact normal use of methods like get/setString(), but will impact the metadata and the type of object returned by getObject() (a byte array instead of a String).
When no connection character set has been specified (properties lc_ctype or encoding with Firebird character set, or charSet or localEncoding with Java character set), Jaybird will currently use the NONE character set. This means that the Firebird server will return the bytes for (VAR)CHAR columns as they are stored, while Jaybird will convert between bytes and Strings using the local platform encoding.
This default has the potential of corrupting data when switching platforms or using the same database with different local encoding, or for transliteration errors when the database character set does not accept some byte combinations. We are currently discussing changing this behavior (see JDBC-257). We haven't decided on the exact changes yet, but most likely the next version of Jaybird will refuse to connect without an explicit connection character set. For the time being, Jaybird will log a warning and add a warning on the Connection when no explicit character set was specified.
Review your use of the connection character sets and change it if you are not specifying it explicitly. Be aware that changing this may require you to fix the data as it is currently stored in your database if your database character set does not match the local platform encoding of your Java application. If you are sure that NONE is the correct character set for you, specify it explicitly in your connection string or connection properties.
Logging in Jaybird 3.0 will be changed. We will probably switch to java.util.logging, but we are also considering slf4j, or upgrading Log4J to version 2.x.
The current implementation of DatabaseMetaData methods do not conform to the JDBC specification when it comes to case sensitivity and quoted object names.
In Jaybird 3.0 meta data methods will no longer do the following:
Remove quotes around object names
Trying the uppercased value, when the original parameter value failed to produce results
For example:
CREATE TABLE tablename (
column1 INTEGER,
"column2" INTEGER
);
In Jaybird 2.2 using getColumns(null, null, "tablename", "column%") will return COLUMN1(!). Unquoted object names are stored uppercase in Firebird, so in Jaybird 3.0 this will produce no rows as tablename does not match TABLENAME.
Changing the query to getColumns(null, null, "TABLENAME", "column%") in Jaybird 2.2 and 3.0 will only produce one row (with column2), as COLUMN1 does not match column%.
In Jaybird 2.2 using getColumns(null, null, "\"TABLENAME\"", "column%") will return column2 as the quotes will be stripped, with Jaybird 3.0 this will produce no rows.
The following file groups can be found in distribution package:
jaybird-2.2.
7
.jar
– archive containing JCA/JDBC driver, implementation of
connection pooling and statement pooling interfaces, and JMX
management class. It requires JCA 1.5.
jaybird-full-2.2.
7
.jar
– merge of jaybird-2.2.
7
.jar
and connector-api-1.5.jar
.
This archive can be used for standalone Jaybird deployments, it
should not be used within application servers.
jaybird-2.2.7-sources.jar – archive containing the sources of Jaybird (specific to this JDK version); for including Jaybird sources in your IDE.
lib/connector-api-1.5.jar
– archive containing JCA 1.5 classes (required dependency).
lib/antlr-runtime-3.4.jar – archive containing ANTLR runtime classes, required for generated keys functionality (optional dependency).
lib/log4j-core.jar
– archive containing core Log4J classes that provide logging
(optional dependency).
Jaybird has compile-time and run-time dependencies on the JCA 1.5 classes. Additionally, if Log4J classes are found in the class path, it is possible to enable extensive logging inside the driver. If the ANTLR runtime classes are absent, the generated keys functionality will not be available.
Native dependencies (required only for Type 2 and Embedded):
jaybird22.dll
– Windows 32-bit
jaybird22_x64.dll
– Windows 64-bit
libjaybird22.so – Linux 32-bit (x86)
libjaybird22_x64.so – Linux 64-bit (AMD/Intel 64)
The Windows DLLs have been built with Microsoft Visual Studio 2010 SP1. To use the native or embedded driver, you will need to install the Microsoft Visual C++ 2010 SP 1 redistributable available at:
x86: http://www.microsoft.com/download/en/details.aspx?id=8328
x64: http://www.microsoft.com/download/en/details.aspx?id=13523
Jaybird JCA/JDBC driver is distributed under the GNU Lesser General Public License (LGPL). Text of the license can be obtained from http://www.gnu.org/copyleft/lesser.html.
Using Jaybird (by importing Jaybird's public interfaces in your Java code), and extending Jaybird by subclassing or implementation of an extension interface (but not abstract or concrete class) is considered by the authors of Jaybird to be dynamic linking. Hence our interpretation of the LGPL is that the use of the unmodified Jaybird source does not affect the license of your application code.
Even more, all extension interfaces to which application might want to link are released under dual LGPL/modified BSD license. Latter is basically “AS IS” license that allows any kind of use of that source code. Jaybird should be viewed as an implementation of that interfaces and LGPL section for dynamic linking is applicable in this case.
The distribution package contains the normal sources in jaybird-2.2.7-sources.jar; this file does not include the sources of the tests, nor the sourcecode for other JDK-versions.
Full source code, including tests and build files,
can be obtained from the Subversion repository at SourceForge.net.
The repository URL
is
svn://svn.code.sf.net/p/firebird/code/client-java
Alternatively source code can be viewed online at
http://sourceforge.net/p/firebird/code/
The most detailed information can be found in the Jaybird Frequently Asked Questions (FAQ). The FAQ is included in the distribution, and is available on-line in several places.
JaybirdWiki is available at http://jaybirdwiki.firebirdsql.org/
Jaybird 2.1 Programmers Manual: http://www.firebirdsql.org/file/documentation/drivers_documentation/Jaybird_2_1_JDBC_driver_manual.pdf
The best place to start is the FAQ. Many details for using Jaybird with various programs are located there. Below are some links to useful web sites.
The http://groups.yahoo.com/group/Firebird-Java and corresponding mailing-list Firebird-Java@yahoogroups.com
The code for Firebird and this driver are on http://sourceforge.net/projects/firebird
The Firebird project home page http://www.firebirdsql.org
There are several ways you can contribute to Jaybird or Firebird in general:
Participate on the mailinglists (see http://www.firebirdsql.org/en/mailing-lists/)
Report bugs or submit patches on the tracker (see below)
Become a developer (for Jaybird contact us on Firebird-Java, for Firebird in general, use the Firebird-devel mailing-list)
Become a paying member or sponsor of the Firebird Foundation (see http://www.firebirdsql.org/en/firebird-foundation/)
See also http://www.firebirdsql.org/en/consider-your-contribution/
The developers follow the Firebird-Java@yahoogroups.com list. Join the list and post information about suspected bugs. List members may be able to help out to determine if it is an actual bug, provide a workaround and get you going again, whereas bug fixes might take awhile.
If you are sure that this is a bug you can report it in the Firebird bug tracker, project “Java Client (Jaybird)” at http://tracker.firebirdsql.org/browse/JDBC
When reporting bugs, please provide a minimal, but complete reproduction, including databases and sourcecode to reproduce the problem. Patches to fix bugs are also appreciated. Make sure the patch is against a recent trunk version of the code.
Please send corrections, suggestions, or additions to these Release Notes to to the mailing list at Firebird-Java@yahoogroups.com.
Jaybird provides different JDBC URLs for different usage scenarios:
jdbc:firebirdsql://host[:port]/<database>
Default
URL, will connect to the database using Type 4 JDBC driver using the
Java implementation of the Firebird wire-protocol. Best suited for
client-server applications with dedicated database server. Port can
be omitted (default value is 3050), host name must be present.
The
<database>
part should be replaced with the database alias or the path to the
database. In general it is advisable to uses database aliases instead
of the path the file.
On
Linux the root
/
should be included in the path. A database located on
/opt/firebird/db.fdb
should use the URL below (note the double slash after port!).
jdbc:firebirdsql://host:port//opt/firebird/db.fdb
Deprecated
but still available alternative URL:
jdbc:firebirdsql:host[/port]:<database>
jdbc:firebirdsql:native:host[/port]:<database>
Type 2 driver, will connect to the database using
client library (fbclient.dl
l
on Windows, and libfbclient.so
on Linux). Requires correct installation of the client library.
jdbc:firebirdsql:local:
<database>
Type 2 driver in local mode. Uses client library as in previous case, however will not use socket communication, but rather access database directly. Requires correct installation of the client library.
jdbc:firebirdsql:embedded:
<database>
Similar to the Firebird client library, however
fbembed.dll
on Windows and libfbembed.so
on Linux are used. Requires correctly installed and configured
Firebird embedded library.
Jaybird 2.2 provides a Type 2 JDBC driver that uses the native client library to connect to the databases. Additionally Jaybird 2.2 can use the embedded version of Firebird so Java applications do not require a separate server setup.
However the Type 2 driver has its limitations:
Due to multi-threading issues in the Firebird client library as well as in the embedded server version, it is not possible to access a single connection from different threads simultaneously. When using the client library only one thread is allowed to access a connection at a time. Access to different connections from different threads is however allowed. Client library in local mode and embedded server library on Linux do not allow multithreaded access to the library. Jaybird provides necessary synchronization in Java code, however the mutex is local to the classloader that loaded the Jaybird driver.
Care should be taken when deploying applications in web or application servers: put jar files in the main library directory of the web and/or application server, not in the library directory of the web or enterprise application (WEB-INF/lib directory or in the .EAR file).
The Type 2 JDBC driver requires the Jaybird JNI library to be installed and available to the Java Virtual Machine. Precompiled binaries for Windows and Linux platforms are distributed with Jaybird.
Please note that Jaybird 2.2 provides an update to the JNI libraries to support new features. It is not compatible with the JNI library for Jaybird 2.1 or earlier.
jaybird22.dll
/ jaybird22_x64.dll
is a precompiled binary for the
Windows platform. It was successfully tested with Windows XP and
Windows 7, but there should be no issues in other Windows OS
versions (as long as the MS Visual C++ 2010 SP1 distributable is
available).
The library should be copied into a directory in the
PATH
environment variable, or be made available to the JVM using the
java.library.path
system property.
libjaybird22.so
/ libjaybird22_x64.so
is a precompiled binary for the
Linux platform (AMD/Intel). It must be available via the
LD_LIBRARY_PATH
environment variable, or be made available to the JVM using the
java.library.path
system property.
Dependent libraries (libfbclient.so
or libfbembed.so)
need to be on the LD_LIBRARY_PATH.
The java.library.path
is ignored for these libraries as they are loaded from the JNI
library, and not from Java.
Some Firebird distributions will not
create libfbclient.so
(but only libfbclient.so.2
and .so.2.5),
you will need to add a symlink with the name as expected by Jaybird.
Other platforms can easily compile the JNI
library by checking out the Jaybird sources from the CVS and using
./build.sh
compile-native
command in the directory with
checked out sources.
After making Jaybird JNI library available to the
JVM, the application has to tell driver to start using this by either
specifying TYPE2 or LOCAL type in the connection pool or data source
properties or using appropriate JDBC URL when connecting via
java.sql.DriverManager
.
The Embedded Server JDBC driver uses the same JNI library and configuration steps for the Type 2 JDBC driver.
There is however one issue related to the
algorithm of Firebird Embedded Server installation directory
resolution. Firebird server uses pluggable architecture for
internationalization. By default server loads fbintl.dll
or libfbintl.so
library that contains various character encodings and collation
orders. This library is expected to be installed in the intl/
subdirectory of the server installation. The algorithm of directory
resolution is the following:
FIREBIRD
environment variable.
RootDirectory
parameter in the firebird.conf
file.
The directory where server binary is located.
When Embedded Server is used from Java and no
FIREBIRD
environment variable is specified, it tries to find firebird.conf
in the directory where application binary is located. In our case
application binary is JVM and therefore Embedded Server tries to find
its configuration file in the bin/
directory of the JDK or JRE installation. Same happens to the last
item of the list. In most cases this is not desired behavior.
Therefore, if the application uses
character encodings, UDFs or wants to fine-tune server behavior
through the configuration file, the FIREBIRD
environment variable must be specified and point to the installation
directory of the Embedded Server, e.g. current working directory.
Upto Jaybird 2.0 only one client library could be
loaded in a single JVM. That could be either an embedded Firebird
library (fbembed.dll
/libfbembed.so
),
or Firebird client library (fbclient.dll
/libfbclient.so
).
This could lead to problems, For example, if embedded Firebird was
used first, the JDBC driver would access the database file directly
instead of using the local IPC protocol if only the path to the
database was specified. It was not possible to change this without
restarting the JVM.
Since Jaybird 2.1, Jaybird is able to correctly load arbitrary number of shared libraries that implement the ISC API and forward the requests correctly depending on the type of the driver being used.
Events is one of the unique features in the Firebird RDBMS and allows asynchronous notification of the applications about named events that happen in the database. Information on this feature can found in the free IB 6.0 documentation set as well as in The Firebird Book by Helen Borrie.
The interfaces and classes for the event support
can be found in org.firebirdsql.event
package, which includes:
EventManager
interface to register for the synchronous and asynchronous
notification about the events in the database;
EventListener
interface which has to be implemented by the application that wants
to participate in the asynchronous notification;
DatabaseEvent
interface which represents the object that will be passed to the
EventListener
notification method;
Implementation of the above interfaces:
FBEventManager
and FBDatabaseEvent
.
Please note, that each instance of
FBEventManager
will open a new socket connection to the Firebird server on the port
specified by Firebird.
Similar to other JDBC extensions in Jaybird, the interfaces are released under the modified BSD license, the implementation of the code is released under LGPL license.
Default holdable result sets (closed ResultSet in auto-commit mode)
This connection property allows to create holdable result sets by default. This is needed as a workaround for the applications that do not follow JDBC specification in regard to the auto-commit mode.
Specifically, such applications open a result set and, while traversing it, execute other statements using the same connection. According to JDBC specification the result set has to be closed if another statement is executed using the same connection in auto-commit mode. Among others the OpenOffice/LibreOffice Base users have problems with the JDBC compatibility in Jaybird.
The property is called:
defaultResultSetHoldable
as connection property for JDBC URL or for java.sql.DriverManager
class and no or empty value should be assigned to it; it has an
alias defaultHoldable
to simplify the typing;
isc_dpb_result_set_holdable
as a DPB member;
FirebirdConnectionProperties
interface methods isDefaultResultSetHoldable()
and setDefaultResultSetHoldable(boolean)
Note, the price for using this feature is that each holdable result set will be fully cached in memory. The memory occupied by it will be released when the statement that produced the result set is either closed or re-executed.
Jaybird provides support for
updatable result sets. This feature allows a Java application to
update the current record using the update
XXX
methods of java.sql.ResultSet
interface. Updates are performed within the current transaction using
a best row identifier in WHERE
clause. This sets the following limitation on the result set
“updatability”:
the SELECT
references a single table;
all columns not referenced in
SELECT
permit NULL
s
(otherwise INSERT
s
will fail);
the SELECT
statement does not contain DISTINCT
predicate, aggregate functions, joined tables or stored procedures;
the SELECT
statement references all columns from the table primary key
definition or an RDB$DB_KEY
column.
Jaybird provides full support of the Firebird Services API that allows Java applications to perform various server management tasks:
database backup/restore on remote server; it is possible to performs metadata-only backups, switch the garbage collection during backup off, restore databases with no validity constraints or active indices, etc.
database maintenance, e.g. database shutdown, sweep, changing the forced writes settings, changing SQL dialect of the database, shadow management, etc.
retrieving database statistics including header page statistics, system table statistics, data page statistics and index statistics.
user management, including adding, modifying, and deleting user accounts.
Jaybird provides extensions to some
JDBC interfaces. JDBC extension interface classes are released under
modified BSD license, on “AS IS” and “do what you
want” basis, this should make linking to these classes safe
from the legal point of view. All classes belong to
org.firebirdsql.jdbc.*
package. The table below shows all JDBC extensions present in Jaybird
with a driver version in which the extension was introduced.
JDBC extensions |
|||
---|---|---|---|
Interface |
Since |
Method name |
Description |
|
2.0 |
|
Create new instance of
|
|
|
|
Connect to the Firebird database using the specified connection properties. |
|
2.0 |
see JDBC connection properties section for more details. |
|
|
1.5 |
|
Create new BLOB in the database.
Later this BLOB can be passed as a parameter into
|
|
1.5 |
|
Get connection character encoding. |
|
2.0 |
|
Get the TPB parameters for the specified transaction isolation level. |
|
2.0 |
|
Create an empty transaction parameter buffer. |
|
2.0 |
|
Set TPB parameters for the specified transaction isolation level. The newly specified mapping is valid for the whole connection lifetime. |
|
2.0 |
|
meters are effective until the transaction isolation is changed. |
|
|
|
Get source code for the specified stored procedure name. |
|
|
|
Get source code for the specified trigger name. |
|
|
|
Get source code for the specified view name. |
|
1.5 |
|
Extension that allows to get more precise information about outcome of some statement. |
|
1.5 |
|
Check if this statement has open result set. Correctly works only when auto-commit is disabled. Check method documentation for details. |
|
1.5 |
|
Get current result set. Behaviour
of this method is similar to the behavior of the
|
|
1.5 |
|
Check if this statement is still valid. Statement might be invalidated when connection is automatically recycled between transactions due to some irrecoverable error. |
|
2.0 |
|
Get execution plan for the last executed statement. |
|
2.0 |
|
Get the execution plan of this prepared statement. |
|
2.0 |
|
Get the statement type of this prepared statement. |
|
1.5 |
|
Mark this callable statement as a call of the selectable procedure. By default callable statement uses EXECUTE PROCEDURE SQL statement to invoke stored procedures that return single row of output parameters or a result set. In former case it retrieves only the first row of the result set. |
|
2.0 |
|
Get execution plan for this result set. |
|
1.5 |
|
Method “detaches” a BLOB object from the underlying result set. Lifetime of “detached” BLOB is limited by the lifetime of the connection. |
|
1.5 |
|
Check if this BLOB is segmented. Seek operation is not defined for the segmented BLOBs. |
|
1.5 |
|
Opens an output stream at the specified position, allows modifying BLOB content. Due to server limitations only position 0 is supported. |
|
1.5 |
|
Get corresponding BLOB instance. |
|
1.5 |
|
Change the position from which BLOB content will be read, works only for stream BLOBs. |
|
2.0 |
interface is equivalent to the java.sql.Savepoint interface introduced in JDBC 3.0 specification, however allows using Firebird savepoints also in JDBC 2.0 (JDK 1.3.x) applications. |
The table below lists the properties for the
connections that are obtained from this data source. Commonly used
parameters have the corresponding getter and setter methods, the rest
of the Database Parameters Block parameters can be set using
setNonStandardProperty
setter method.
Property |
Getter |
Setter |
Description |
---|---|---|---|
|
+ |
+ |
(deprecated) Path to the database in the format
|
serverName |
+ |
+ |
Hostname or IP address of the Firebird server |
portNumber |
+ |
+ |
Portnumber of the Firebird server |
databaseName |
+ |
+ |
Database alias or full-path |
|
+ |
+ |
Type of the driver to use. Possible values are:
|
|
+ |
+ |
Size of the buffer used to transfer BLOB content. Maximum value is 64k-1. |
|
+ |
+ |
Size of the socket buffer. Needed on some Linux machines to fix performance degradation. |
|
+ |
+ |
Number of cache buffers (in database pages) that will be allocated for the connection. Makes sense for ClassicServer only. |
|
+ |
+ |
Character set for the connection. Similar to
|
|
+ |
+ |
Character encoding for the connection. See Firebird documentation for more information. |
|
+ |
+ |
Path to the properties file containing character translation map. |
|
+ |
+ |
Corresponding password. |
|
+ |
+ |
SQL role to use. |
|
+ |
+ |
Name of the user that will be used by default. |
|
+ |
+ |
Boolean flag tells driver whether stream BLOBs should be created by the driver, by default “false”. Stream BLOBs allow “seek” operation to be called, however due to a bug in gbak utility they are disabled by default. |
|
+ |
+ |
Boolean flag tells driver to assume that standard UDFs are defined in the database. This extends the set of functions available via escaped function calls. This does not affect non-escaped use of functions. |
|
+ |
+ |
Boolean flag tells driver to construct the default result set to be holdable. This prevents it from closing in auto-commit mode if another statement is executed over the same connection. |
|
+ |
+ |
TPB mapping for different transaction isolation modes. |
|
+ |
+ |
Default transaction isolation level. All newly created connections will have this isolation level. One of:
|
|
+ |
+ |
Integer value from |
|
|
+
|
Allows to set any valid connection property that does not have corresponding setter method. Two setters are available:
|
connectTimeout |
+ |
+ |
The connect timeout in seconds. For the Java wire protocol detects unreachable hosts, for JNI (native protocol) only defines a timeout during the op_accept phase after connecting to the server. |
The Jaybird driver is not officially JDBC-compliant as the certification procedure is too expensive. The following lists some of the differences between JDBC specification and Jaybird implementation. This list is not exhaustive.
The following optional features and the methods for their support are not implemented:
java.sql.Array
data type is not (yet) supported
java.sql.Blob
does not implement following methods:
position(Blob,
long)
and position(byte[],
long)
; Firebird does not provide any server-side
optimization for these calls, client application must fetch
complete BLOB content from the server to do pattern search.
truncate(long)
;
Firebird does not provide such functionality on the server side,
application must fetch old BLOB from the server and pump old
content into a newly created BLOB.
java.sql.Connection
getCatalog()
and setCatalog(String)
are not supported by Firebird server
getTypeMap()
and setTypeMap(Map)
are not supported
java.sql.Ref
data type is not supported by Firebird server
java.sql.SQLData
data type is not supported by Firebird server
java.sql.SQLInput
is not supported
java.sql.SQLOutput
is not supported
java.sql.SQLXML is not supported
java.sql.RowId is not supported
java.sql.NClob is not supported
java.sql.Statement
cancel()
is implemented, but not fully supported by Jaybird
java.sql.Struct
data type is not supported by server.
The following methods are implemented, but deviate from the specification:
java.sql.Statement
get
/
setMaxFieldSize
does nothing, Firebird server does not support this feature.
get
/
setQueryTimeout
does nothing, Firebird server does not support this feature.
java.sql.PreparedStatement
setObject(int
index, Object object, int type)
Target SQL type is
determined from the class of the passed object and corresponding
parameter is ignored.
setObject(int
index, Object object, int type, int scale)
Same as
above, type and scale are ignored.
java.sql.ResultSetMetaData
isReadOnly()
always returns false
isWritable()
always returns true
isDefinitivelyWritable()
always returns true
Jaybird has some implementation-specific issues that should be considered during development.
Jaybird behaves differently not only when different result set types are used but also whether the connection is in auto-commit mode or not.
ResultSet.TYPE_FORWARD_ONLY
result sets when used in auto-commit mode are completely cached on
the client before the execution of the query is finished. This leads
to the increased time needed to execute statement, however the
result set navigation happens almost instantly. When auto-commit
mode is switched off, only part of the result set specified by the
fetch size is cached on the client.
ResultSet.TYPE_SCROLL_INSENSITIVE
result sets are always cached on the client. The reason is quite
simple – the Firebird API does not provide scrollable cursor
support, navigation is possible only in one direction.
ResultSet.HOLD_CURSORS_OVER_COMMIT
holdability is supported in Jaybird only for result sets of type
ResultSet.TYPE_SCROLL_INSENSITIVE
.
For other result set types driver will throw an exception.
This interface can be used only to obtain
information about the IN parameters. Also it is not allowed to call
the PreparedStatement.getParameterMetaData
method before all of the OUT parameters are registered. Otherwise the
corresponding method of CallableStatement
throws an SQLException
,
because the driver tries to prepare the procedure call with incorrect
number of parameters.
Jaybird JDBC driver always uses connection encoding when converting array of bytes into character stream. The BLOB SUB_TYPE 1 fields allow setting the character encoding for the field. However when the contents of the field is sent to the client, it is not converted according to the character set translation rules in Firebird, but is sent “as is”. When such fields are accessed from a Java application via Jaybird and character set of the connection does not match the character encoding of the field, conversion errors might happen. Therefore it is recommended to convert such fields in the application using the appropriate encoding.
Current JCA implementation does not support
XAResource.forget(Xid)
.
It might be important in cases where a distributed transaction -
that was at some time in-limbo - was either committed or rolled back
by the database administrator. Such transactions appear to Jaybird as
successfully completed, however XA specification requires resource
manager to “remember” such transaction until the
XAResource.forget(Xid)
is called.
The reference implementation of javax.sql.rowset included with Java in package com.sun.rowset does not correctly look up columns by name as it ignores column aliases and only allows look up by the original column name5 (this specifically applies to com.sun.rowset.CachedRowSetImpl).
We advise you to either only access columns by their index or use an implementation which correctly uses the column label for column lookup (which is either the alias or the original column name if no alias was defined).
Jaybird 2.2.1 introduced the connection property columnLabelForName for backwards compatible behavior of ResultSetMetaData#getColumnName(int). Set property to true for backwards compatible behavior (getColumnName() returns the column label); don't set the property or set it to false for JDBC-compliant behavior (recommended).
Jaybird 2.2.4 introduces support for the Firebird 3 BOOLEAN type. A boolean field can also be set with all numeric setters and the string setter (as implied by JDBC 4.1 appendix B).
For numeric types, currently only 0 will set to false and all other values will set to true. This is something that might change in the future. Only 0 for false and 1 for true are guaranteed, in the future we might decide to throw a conversion exception for other values!
For string types we currently set true for "true", "T", "Y" and "1" (case insensitive, ignoring whitespace), all other values will set false; this is for compatibility with the current getBoolean behaviour of FBStringField. This is something that might change in the future. Only "true" and "1" for true and "false" and "0" for false are guaranteed (case insensitive, ignoring whitespace), in the future we might decide to throw a conversion exception for other values!
When using string or numeric setters for a boolean field we strongly recommend to only use the guaranteed values (0, 1, "0", "1", "true" and "false"). Better yet: use the boolean setter instead.
As described in Important changes to Datasources, the ConnectionPoolDataSource implementations in org.firebirdsql.pool contain some serious issues. The connection pool capability which depends on these classes will be removed in Jaybird 3.0.
This change leaves only the ConnectionPoolDataSource implementations in org.firebirdsql.ds (for use by application server connection pools). There are no plans to reintroduce a new standalone connection pooling capability. We probably will migrate some of the features like statement pooling to the normal JDBC driver.
If you require standalone connection pooling, or use an application server which has no built-in connectionpool, please consider using a third-party connection pool like c3p0, DBCP or HikariCP.
WARNING: This section provides information on deprecated classes,
See Important changes to Datasources
Connection pooling provides effective way to handle physical database connections. It is believed that establishing new connection to the database takes some noticeable amount or time and in order to speed things up one has to reuse connections as much as possible. While this is true for some software and for old versions of Firebird database engine, establishing connection is hardly noticeable with Firebird 1.0.3 and Firebird 1.5. So why is connection pooling needed?
There are few reasons for this. Each good connection pool provides a possibility to limit number of physical connections established with the database server. This is an effective measure to localize connection leaks. Any application cannot open more physical connections to the database than allowed by connection pool. Good pools also provide some hints where connection leak occurred. Another big advantage of connection pool is that it becomes a central place where connections are obtained, thus simplifying system configuration. However, main advantage of good connection pool comes from the fact that in addition to connection pooling, it can pool also prepared statement. Tests executed using AS3AP benchmark suite show that prepared statement pooling might increase speed of the application by 100% keeping source code clean and understandable.
When some statement is used more than one time, it makes sense to use prepared statement. It will be compiled by the server only once, but reused many times. It provides significant speedup when some statement is executed in a loop. But what if some prepared statement will be used during lifetime of some object? Should we prepare it in object's constructor and link object lifetime to JDBC connection lifetime or should we prepare statement each time it is needed? All such cases make handling of the prepared statements hard, they pollute application's code with irrelevant details.
Connection and statement pooling remove such details from application's code. How would the code in this case look like? Here's the example
Example 1. Typical JDBC code with statement pooling |
|
---|---|
001
002
003
004
005
006
007
008
009
010
011
012
013
014
015
016
|
...
Connection connection = dataSource.getConnection();
try {
PreparedStatement ps = connection.prepareStatement(
“SELECT * FROM test_table WHERE id = ?”);
try {
ps.setInt(1, id);
ResultSet rs = ps.executeQuery();
while (rs.next()) {
// do something here
}
} finally {
ps.close();
}
} finally {
connection.close();
}
...
|
Lines 001-018 show typical code when
prepared statement pooling is used. Application obtains JDBC
connection from the data source (instance of javax.sql.DataSource
interface), prepares some SQL statement as if it is used for the
first time, sets parameters, and executes the query. Lines 012 and
015 ensure that statement and connection will be released under any
circumstances. Where do we benefit from the statement pooling? Call
to prepare a statement in lines 004-005 is intercepted by the pool,
which checks if there's a free prepared statement for the specified
SQL query. If no such statement is found it prepares a new one. In
line 013 prepared statement is not closed, but returned to the pool,
where it waits for the next call. Same happens to the connection
object that is returned to the pool in line 016.
Jaybird connection pooling classes belong to
org.firebirdsql.pool.*
package.
Description of some connection pool classes. |
|
---|---|
|
Base class for all connection pools. Can be used for implementing custom pools, not necessarily for JDBC connections. |
|
Subclass of |
|
Implementation of
|
|
Jaybird specific implementation of
|
|
Implementation of |
|
Implementation of |
|
Implementation of |
This class is a corner stone of connection and
statement pooling in Jaybird. It can be instantiated within the
application as well as it can be made accessible to other
applications via JNDI. Class implements both java.io.Serializable
and javax.naming.Referenceable
interfaces, which allows using it in a wide range of web and
application servers.
Class implements both
javax.sql.ConnectionPoolDataSource
and javax.sql.XADataSource
interfaces. Pooled connections returned by this class implement
javax.sql.PooledConnection
and javax.sql.XAConnection
interfaces and can participate in distributed JTA transactions.
Class provides following configuration properties:
This group contains properties defined in the JDBC specification and should be standard to all connection pools.
Property |
Getter |
Setter |
Description |
---|---|---|---|
|
+ |
+ |
Maximum time in milliseconds after which idle connection in the pool is closed. |
|
+ |
+ |
Maximum number of open physical connections. |
|
+ |
+ |
Minimum number of open physical connections. If value is greater than 0, corresponding number of connections will be opened when first connection is obtained. |
|
+ |
+ |
Maximum size of prepared statement pool. If 0, statement pooling is switched off. When application requests more statements than can be kept in pool, Jaybird will allow creating that statements, however closing them would not return them back to the pool, but rather immediately release the resources. |
This group of properties are specific to the Jaybird implementation of the connection pooling classes.
Property |
Getter |
Setter |
Description |
---|---|---|---|
|
+ |
+ |
Maximum time in milliseconds during which application can be blocked waiting for a connection from the pool. If no free connection can be obtained, exception is thrown. |
|
+ |
+ |
Period in which pool will try to obtain new connection while blocking the application. |
|
+ |
+ |
Allows to switch connection pooling off. |
|
+ |
+ |
Allows to switch statement pooling off. |
|
+ |
+ |
Statement that will be used to “ping” JDBC connection, in other words, to check if it is still alive. This statement must always succeed. |
|
+ |
+ |
Time during which connection is believed to be valid in any case. Pool “pings” connection before giving it to the application only if more than specified amount of time passed since last “ping”. |
This group contains read-only properties that provide information about the state of the pool.
Property |
Getter |
Setter |
Description |
---|---|---|---|
|
+ |
- |
Tells how many free connections are in the
pool. Value is between 0 and |
|
+ |
- |
Tells how many connections were taken from the pool and are currently used in the application. |
|
+ |
- |
Total size of open connection. At the pool
creation – 0, after obtaining first connection –
between |
|
+ |
- |
Deprecated. Same as |
This class is a wrapper for
FBConnectionPoolDataSource
converting interface from javax.sql.ConnectionPoolDataSource
to javax.sql.DataSource
.
It defines same properties as FBConnectionPoolDataSource
does.
Pool implementation shipped with
Jaybird can provide hints for the application where the connection
was obtained from the pool, when it was released back to the pool,
when the statement was prepared. Such information is written into the
log when appropriate system properties are set to true
.
Property name |
Description |
---|---|
|
Enables logging inside driver. This is the
essential property, if it is not present or set to When it is set to When physical connection is added to
the pool – When a maximum pool capacity is reached
– When connection is obtained from pool –
When connection is released back to
pool – Whether pool supports open statements
across transaction boundaries – |
|
Enables logging of the thread stack trace when debugging is enabled and: Connection is allocated from the pool –
Thread is blocked while waiting for a
free connection – |
|
When statement caching is used and debugging is enabled, following information is logged: When a statement is prepared –
When statement cache is cleaned –
When statement is obtained from or
returned back to pool – |
1With java.sql.Timestamp the 100 microsecond precision is only available through getNanos() and setNanos()
4To be removed in Jaybird 3.0
5See JDBC-162 and http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7046875 for details