About MariaDB Connector/J

MariaDB Connector/J is used to connect applications developed in Java to MariaDB and MySQL databases using the standard JDBC API. The library is LGPL licensed.

Introduction

MariaDB Connector/J is a Type 4 JDBC driver. It was developed specifically as a lightweight JDBC connector for use with MySQL and MariaDB database servers. It's originally based on the Drizzle JDBC code, and with a lot of additions and bug fixes.

Obtaining the driver

The driver source code can be downloaded from: https://downloads.mariadb.org/connector-java/

Pre-built .jar files can be downloaded from: https://code.mariadb.com/connectors/java/

Installing the driver

Installation of the client library is very simple, the jar file should be saved in an appropriate place for your application and the classpath of your application altered to include MariaDB Connector/J rather than your current connector.

Using maven :

<dependency>
    <groupId>org.mariadb.jdbc</groupId>
    <artifactId>mariadb-java-client</artifactId>
    <version>xxx</version>
</dependency>

Requirements

• Java 7 (until April 2015) or 8
• com.sun.JNA is used by some library functions and a jar is available at https://github.com/twall/jna
  • only needed when connecting to the server with unix sockets or windows shared memory
• A MariaDB or MySQL Server
• maven (only if you want build from source)

Source code

The source code is available on GitHub: https://github.com/MariaDB/mariadb-connector-j and the most recent development version can be obtained using the following command:

git clone https://github.com/MariaDB/mariadb-connector-j.git

License

GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

Building and testing the driver

The section deals with building the connector from source and testing it. If you have downloaded a ready built connector, in a jar file, then this section may be skipped.

MariaDB Client Library for Java Applications uses maven for build. You first need to ensure you have both java and maven installed on your server before you can build the driver.

To run the unit test, you'll need a MariaDB or MySQL server running on localhost (on default TCP port 3306) and a database called 'test', and user 'root' with empty password

git clone https://github.com/MariaDB/mariadb-connector-j.git #  Or, unpack the source distribution tarball
cd mariadb-connector-j
# For the unit test run, start local mysqld mysqld, 
# ensure that user root with empty password can login
mvn package
# If you want to build without running unit  tests, use
# mvn -Dmaven.test.skip=true package

After that, you should have JDBC jar mariadb-java-client-x.y.z.jar in the 'target' subdirectory

Using the driver

The following subsections show the formatting of JDBC connection strings for MariaDB, MySQL database servers. Additionally, sample code is provided that demonstrates how to connect to one of these servers and create a table.

Driver Manager

Applications designed to use the driver manager to locate the entry point need no further configuration, MariaDB Connector/J will automatically be loaded and used in the way any previous MySQL driver would have been.

Driver Class

Please note that the driver class provided by MariaDB Connector/J is not com.mysql.jdbc.Driver but org.mariadb.jdbc.Driver!

Connection strings

Format of the JDBC connection string is

jdbc:(mysql|mariadb):[replication:|failover:]//<hostDescription>[,<hostDescription>...]/[database][?<key1>=<value1>[&<key2>=<value2>]] 

HostDescription:

<host>[:<portnumber>]  or address=(host=<host>)[(port=<portnumber>)][(type=(master|slave))]

Host must be a DNS name or IP address. In case of ipv6 and simple host description, the IP address must be written inside brackets. The default port is 3306. The default type is master. If replication failover is set, by default the first host is master, and the others are slaves.

Examples :

• localhost:3306
• [2001:0660:7401:0200:0000:0000:0edf:bdd7]:3306
• somehost.com:3306
• address=(host=localhost)(port=3306)(type=master)

Failover parameters

Failover was introduced in Connector/J 1.2.0.

Optional URL parameters

General remark: Unknown options accepted and are silently ignored.

Following options are currently supported.

Failover/High availability URL parameters

JDBC API Implementation Notes

Streaming result sets

By default, Statement.executeQuery() will read full result set from server before returning. With large result sets, this will require large amounts of memory. Better behavior in this case would be reading row-by-row, with ResultSet.next(), so called "streaming" feature. It is activated using Statement.setFetchSize(Integer.MIN_VALUE)

Prepared statements

The driver only uses text protocol to communicate with the database. Prepared statements (parameter substitution) is handled by the driver, on the client side.

CallableStatement

Callable statement implementation won't need to access stored procedure metadata (mysql.proc) table if both of following are true

• CallableStatement.getMetadata() is not used
• Parameters are accessed by index, not by name

When possible, following the two rules above provides both better speed and eliminates concerns about SELECT privileges on the mysql.proc table.

Optional JDBC classes

Following optional interfaces are implemented by the org.mariadb.jdbc.MySQLDataSource class : javax.sql.DataSource, javax.sql.ConnectionPoolDataSource, javax.sql.XADataSource

Usage examples

The following code provides a basic example of how to connect to a MariaDB or MySQL server and create a table.

Creating a table on a MariaDB or MySQL Server

Connection  connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "username", "password");
Statement stmt = connection.createStatement();
stmt.executeUpdate("CREATE TABLE a (id int not null primary key, value varchar(20))");
stmt.close();
connection.close();