Jaybird Frequently Asked Questions

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1 Jaybird

1.1 Where do I get Jaybird?

1.1.1 Maven Jaybird 3.0

Jaybird 3.0 is available from Maven central:

Groupid: org.firebirdsql.jdbc,
Artifactid: jaybird-jdkXX (where XX is 17 or 18)
Version: 3.0.1

For example, for Java 8:


If your application is deployed to a Java EE application server, you will need to exclude the javax.resource:connector-api dependency, and add it as a provided dependency:


If you want to use Type 2 support (native, local or embedded), you need to explicitly include JNA 4.4.0 as a dependency:

</dependency> Jaybird 2.2

Jaybird 2.2 is available on maven, with a separate artifact for each supported Java version.

Groupid: org.firebirdsql.jdbc,
Artifactid: jaybird-jdkXX (where XX is 16, 17 or 18)
Version: 2.2.13

For example:


When deploying to a JavaEE environment, exclude the javax.resource connector-api dependency as this will be provided by the application server.

1.1.2 Download

Firebird can be downloaded from the Firebird website, under Downloads, JDBC Driver.

Alternatively, you can go directly to GitHub and download Jaybird from the jaybird releases.

1.2 Where can I get the sourcecode?

All Jaybird distribution zips contain a jaybird-<version>-sources.zip with the sources used for that specific version. The full Jaybird sourcecode is also available from GitHub in the jaybird repository:


Each release is also tagged in the repository.

1.3 How is Jaybird licensed?

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 an 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 the LGPL section for dynamic linking is applicable in this case.

1.3.1 Which version of the LGPL applies?

Current releases of Jaybird do not explicitly specify an LGPL version. This means that you can choose which version applies. Future versions of Jaybird may specify an explicit version, or be released under a different license.

1.4 Which Java versions are supported?

Jaybird 3.0 supports Java 7 and 8 and has rudimentary support for Java 9.

Jaybird 2.2 supports Java 6, 7 and 8.

Jaybird 2.2.4 added basic support for Java 8 (JDBC 4.2), although not all JDBC 4.2 features are supported or fully implemented.

Jaybird 2.2.7 is the last version to support Java 5, support has been dropped with Jaybird 2.2.8.

Jaybird 2.2 is the last version to support Java 6, support will be dropped with Jaybird 3.0.

1.5 Which Firebird versions are supported?

Jaybird 3.0 supports Firebird versions 2.0 and higher.

Jaybird 3.0 is the last version to support Firebird 2.0 and 2.1. Future versions of Jaybird are not guaranteed to work with version 2.1 and earlier.

Jaybird 2.2 supports all Firebird versions 1.0 and higher. Jaybird 2.2.4 added support for new features of Firebird 3 (eg BOOLEAN support).

Jaybird 2.2 is the last version to support Firebird 1.0 and 1.5. Future versions of Jaybird are not guaranteed to work with these versions.

1.6 Can Jaybird connect to Interbase?

Jaybird does not support Interbase, and as far as we know connecting to Interbase 6.0 and later will fail due to Firebird specific changes in the implementation.

2 Documentation and Support

2.1 Where to get more information on Jaybird

Apart from this FAQ, you can get additional information from:

2.2 Where to get help

2.3 Contributing

There are several ways you can contribute to Jaybird or Firebird in general:

2.4 Reporting Bugs

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.

You can report bugs in the Firebird bug tracker, project "Java Client (Jaybird)"

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 master version of the code. You can also fork the jaybird repository and create pull requests.

3 Connecting to Firebird

3.1 JDBC URLs (java.sql.DriverManager)

3.1.1 Pure Java (default)

Default URL format:


This will connect to the database using the Type 4 JDBC driver using the Java implementation of the Firebird wire-protocol. This is best suited for client-server applications with dedicated database server. Port can be omitted (default value is 3050), host name must be present.

The <host> part is either the hostname, the IPv4 address, or the IPv6 address in brackets (eg [::1]). Use of IPv6 address literals is only supported in Jaybird 3 or newer with Firebird 3 or newer.

The <database> part should be replaced with the database alias or the path to the database. In general it is advisable to use database aliases instead of the path of the database file as it hides implementation details like file locations and OS type.

On Linux the root / should be included in the path. A database located on /opt/firebird/db.fdb should use (note the double slash after port!):


Deprecated, but still supported legacy URL format:


The legacy URL format does not support IPv6 address literals.

3.1.2 Open Office/Libre Office (Pure Java)

Jaybird can be used together with OpenOffice and Libre Office Base. To address some compatibility issues (and differences in interpretation of JDBC specifications) a separate subprotocol is used:


3.1.3 Native (using Firebird client library)

Default URL format:


Legacy URL format:


Type 2 driver, will connect to the database using client library (fbclient.dll on Windows, and libfbclient.so on Linux). Requires correct installation of the client library and - for Jaybird 2.2 or earlier - the Jaybird native library, or - for Jaybird 3.0 - the JNA jar file.


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 and - for Jaybird 2.2 or earlier - the Jaybird native library, or - for Jaybird 3.0 - the JNA jar file.

3.1.4 Embedded Server


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 and - for Jaybird 2.2 or earlier - the Jaybird native library, or - for Jaybird 3.0 - the JNA jar file.

3.2 Character sets

3.2.1 How can I specify the connection character set?

Jaybird provides two connection properties to specify the connection character set:

  • charSet with a Java character set name (alias: localEncoding)

    The Java character set name must map to an equivalent Firebird character set.

  • encoding with a Firebird character set name (alias: lc_ctype)

    The Firebird character set name - with the exception of NONE must map to an equivalent Java character set.

For most applications, use only one of these two properties.

For special situations it is possible to specify both charSet and encoding to convert/reinterpret a character set into another character set, this is usually only necessary to fix data problems.

To phrase differently:

  • encoding=<firebird charset>: use connection encoding <firebird charset> and interpret in the equivalent Java character set

  • charSet=<java charset>: use Firebird equivalent of <java charset> as connection encoding and interpret in

  • encoding=<firebird charset>&charSet=<java charset>: use connection encoding <firebird charset>, but interpret in <java charset>

The handling of Firebird character set NONE is slightly different, see below.

3.2.2 How does character set NONE work?

The Firebird character set NONE is a special case, it essentially means "no character set". You can store anything in it, but conversions to or from this character set are not defined.

When used as a connection character set, Jaybird handles NONE as follows: Jaybird 3.0

  • encoding=NONE means connection encoding NONE and interpret columns with character set NONE using the default JVM encoding, and interpret columns with an explicit character set in their equivalent Java character set

  • encoding=NONE&charSet=ISO-8859-1 the same, but instead of the JVM default, use ISO-8859-1 Jaybird 2.2 and earlier

  • encoding=NONE means use connection encoding NONE and interpret everything using the default JVM encoding

  • encoding=NONE&charSet=ISO-8859-1 the same, but instead of the JVM default, use ISO-8859-1

3.2.3 How can I solve the error "Connection rejected: No connection character set specified"

If no explicit character set has been set, Jaybird 3.0 will reject the connection with an SQLNonTransientConnectionException with message "Connection rejected: No connection character set specified (property lc_ctype, encoding, charSet or localEncoding). Please specify a connection character set (eg property charSet=utf-8) or consult the Jaybird documentation for more information." (see JDBC-446)

In Jaybird 2.2 and earlier, Jaybird would default to connection character set NONE if no character set had been specified (through encoding and/or charSet). This can result in incorrect character set handling when the database is used from different locales.

To prevent potential data-corruption, we no longer allow connecting without an explicit connection character set.

To address this change, explicitly set the connection character set using one of the following options:

  • Use connection property encoding (alias: lc_ctype) with a Firebird character set name.

    Use encoding=NONE for the old default behavior (with some caveats, see How does character set NONE work?).

  • Use connection property charSet (alias: localEncoding) with a Java character set name.

  • Use a combination of encoding and charSet, if you want to reinterpret a Firebird character set in a Java character set other than the default mapping.

  • By providing a default Firebird character set with system property org.firebirdsql.jdbc.defaultConnectionEncoding. Jaybird will apply the specified character set as the default when no character set is specified in the connection properties.

    This property only supports Firebird character set names.

    Use -Dorg.firebirdsql.jdbc.defaultConnectionEncoding=NONE to revert to the old behavior (with some caveats, see How does character set NONE work?).

3.3 How can I enable the Windows "TCP Loopback Fast Path" introduced in Firebird 3.0.2?

Firebird 3.0.2 adds support for "TCP Loopback Fast Path" (SIO_LOOPBACK_FAST_PATH socket option). This is available in Windows 8 / Windows Server 2012 and higher. This feature enables performance optimizations when connecting through localhost (127.0.01 / ::1). It requires support on both client and server side.

Java support for "TCP Loopback Fast Path" was introduced in Java 8 update 60, it can be enabled by specifying the system property jdk.net.useFastTcpLoopback with value true (eg specify -Djdk.net.useFastTcpLoopback=true in your Java commandline).

Unfortunately, Java only has an 'all-or-nothing' support for the "TCP Loopback Fast Path", so Jaybird cannot enable this for you: you must specify this property on JVM startup. On the other hand, this has the benefit that this works for all Jaybird versions, as long as you use Java 8 update 60 or higher (and Firebird 3.0.2 or higher).

4 JDBC Support

4.1 How much of JDBC is supported by Jaybird?

WARNING The information in this section is not 100% up-to-date

Jaybird 3 follows the JDBC 4.3 specification with some features and methods not implemented as they are not supported by Firebird.

Implemented features:

4.2 What parts of JDBC are NOT supported by Jaybird?

WARNING The information in this section is outdated

The following optional features are NOT supported:

The following optional features and the methods that support it are not implemented:

Excluding the unsupported features, the following methods are not yet implemented:

The following methods are implemented, but do not work as expected:

5 Features

5.1 Does Jaybird support connection pooling?

Jaybird itself no longer provides connection pooling. Earlier versions had a DataSource implementation with connection pooling, but this implementation had severe bugs. This implementation (and all other classes in org.firebirdsql.pool) was deprecated in 2.2 and dropped in 3.0.

Jaybird provides a basic DataSource implementation and a ConnectionPoolDataSource implementation. Contrary to its name the latter does not provide a connection pool, but is intended to be used by a connection pool (as implemented in an application server) to create connections for the connection pool.

If your application is built on a Java EE application server, we suggest you use the connection pooling provided by the application server. Either through the resource-adapter of the JCA implementation of Jaybird, or using the java.sql.ConnectionPoolDataSource implementation org.firebirdsql.ds.FBConnectionPoolDataSource.

If you develop standalone applications, or you use an application server without connection pooling, we suggest you use third-party libraries like:

6 Compatibility notes

6.1 Wildfly

The minimal module.xml to use Jaybird 3 under Wildfly is:

<?xml version="1.0" encoding="UTF-8"?>
<module xmlns="urn:jboss:module:1.0" name="org.firebirdsql">
    <resource-root path="jaybird-3.0.x.jar"/>
    <module name="javax.api"/>
    <module name="javax.transaction.api"/>
    <module name="javax.resource.api"/>