A DataSource can be declared via xml in the <tomee-home>/conf/tomee.xml file or in a WEB-INF/resources.xml file using a declaration like the following. All properties in the element body are optional.

<Resource id="myDataSource" type="javax.sql.DataSource">
    accessToUnderlyingConnectionAllowed = false
    alternateUsernameAllowed = false
    connectionProperties = 
    defaultAutoCommit = true
    defaultReadOnly = 
    definition = 
    ignoreDefaultValues = false
    initialSize = 0
    jdbcDriver = org.hsqldb.jdbcDriver
    jdbcUrl = jdbc:hsqldb:mem:hsqldb
    jtaManaged = true
    maxActive = 20
    maxIdle = 20
    maxOpenPreparedStatements = 0
    maxWaitTime = -1 millisecond
    minEvictableIdleTime = 30 minutes
    minIdle = 0
    numTestsPerEvictionRun = 3
    password = 
    passwordCipher = PlainText
    poolPreparedStatements = false
    serviceId = 
    testOnBorrow = true
    testOnReturn = false
    testWhileIdle = false
    timeBetweenEvictionRuns = -1 millisecond
    userName = sa
    validationQuery = 
</Resource>

Alternatively, a DataSource can be declared via properties in the <tomee-home>/conf/system.properties file or via Java VirtualMachine -D properties. The properties can also be used when embedding TomEE via the javax.ejb.embeddable.EJBContainer API or InitialContext

myDataSource = new://Resource?type=javax.sql.DataSource
myDataSource.accessToUnderlyingConnectionAllowed = false
myDataSource.alternateUsernameAllowed = false
myDataSource.connectionProperties = 
myDataSource.defaultAutoCommit = true
myDataSource.defaultReadOnly = 
myDataSource.definition = 
myDataSource.ignoreDefaultValues = false
myDataSource.initialSize = 0
myDataSource.jdbcDriver = org.hsqldb.jdbcDriver
myDataSource.jdbcUrl = jdbc:hsqldb:mem:hsqldb
myDataSource.jtaManaged = true
myDataSource.maxActive = 20
myDataSource.maxIdle = 20
myDataSource.maxOpenPreparedStatements = 0
myDataSource.maxWaitTime = -1 millisecond
myDataSource.minEvictableIdleTime = 30 minutes
myDataSource.minIdle = 0
myDataSource.numTestsPerEvictionRun = 3
myDataSource.password = 
myDataSource.passwordCipher = PlainText
myDataSource.poolPreparedStatements = false
myDataSource.serviceId = 
myDataSource.testOnBorrow = true
myDataSource.testOnReturn = false
myDataSource.testWhileIdle = false
myDataSource.timeBetweenEvictionRuns = -1 millisecond
myDataSource.userName = sa
myDataSource.validationQuery = 

Properties and xml can be mixed. Properties will override the xml allowing for easy configuration change without the need for ${} style variable substitution. Properties are not case sensitive. If a property is specified that is not supported by the declared DataSource a warning will be logged. If a DataSource is needed by the application and one is not declared, TomEE will create one dynamically using default settings. Multiple DataSource declarations are allowed.

See the Common DataSource Configurations page for examples of configuring datasources for Derby, MySQL, Oracle and other common databases.

Supported Properties

Property Type Default Description
accessToUnderlyingConnectionAllowed boolean false If true the raw physical connection to the database can be accessed
alternateUsernameAllowed boolean false If true allow an alternate username and password to be specified on the connection, rather than those specified in the DataSource definition..
connectionProperties String The connection properties that will be sent to the JDBC driver when establishing new connections
defaultAutoCommit boolean true The default auto-commit state of new connections
defaultReadOnly String The default read-only state of new connections If not set then the setReadOnly method will not be called. (Some drivers don't support read only mode, ex: Informix)
definition String
ignoreDefaultValues boolean false use only all set values in this config will need a lot of properties but allow to not set some values
initialSize int 0 The default TransactionIsolation state of new connections.
jdbcDriver String org.hsqldb.jdbcDriver Driver class name
jdbcUrl java.net.URI jdbc:hsqldb:mem:hsqldb Url for creating connections
jtaManaged boolean true Determines wether or not this data source should be JTA managed or user managed.
maxActive int 20 The maximum number of active connections that can be allocated from this pool at the same time, or a negative number for no limit.
maxIdle int 20 The maximum number of connections that can remain idle in the pool, without extra ones being released, or a negative number for no limit.
maxOpenPreparedStatements int 0 The maximum number of open statements that can be allocated from the statement pool at the same time, or zero for no limit.
maxWaitTime time -1 millisecond The maximum number of time that the pool will wait (when there are no available connections) for a connection to be returned before throwing an exception, or -1 to wait indefinitely.
minEvictableIdleTime time 30 minutes The minimum amount of time a connection may sit idle in the pool before it is eligable for eviction by the idle connection evictor (if any).
minIdle int 0 The minimum number of connections that can remain idle in the pool, without extra ones being created, or zero to create none.
numTestsPerEvictionRun int 3 The number of connectionss to examine during each run of the idle connection evictor thread (if any).
password String Default password
passwordCipher String PlainText
poolPreparedStatements boolean false If true, a statement pool is created for each Connection and PreparedStatements created by one of the following methods are pooled:
serviceId String
testOnBorrow boolean true If true connections will be validated before being returned from the pool. If the validation fails, the connection is destroyed, and a new conection will be retrieved from the pool (and validated).
testOnReturn boolean false If true connections will be validated before being returned to the pool. If the validation fails, the connection is destroyed instead of being returned to the pool.
testWhileIdle boolean false If true connections will be validated by the idle connection evictor (if any). If the validation fails, the connection is destroyed and removed from the pool
timeBetweenEvictionRuns time -1 millisecond The number of milliseconds to sleep between runs of the idle connection evictor thread. When set to a negative number, no idle connection evictor thread will be run.
userName String sa Default user name
validationQuery String The SQL query that will be used to validate connections from this pool before returning them to the caller. If specified, this query MUST be an SQL SELECT statement that returns at least one row.
LogSql boolean false Wether SQL queries should be logged or not

accessToUnderlyingConnectionAllowed

If true the raw physical connection to the database can be accessed using the following construct:

Connection conn = ds.getConnection();
Connection rawConn = ((DelegatingConnection) conn).getInnermostDelegate();
...
conn.close()

Default is false, because misbehaving programs can do harmfull things to the raw connection shuch as closing the raw connection or continuing to use the raw connection after it has been assigned to another logical connection. Be careful and only use when you need direct access to driver specific extensions.

NOTE: Do NOT close the underlying connection, only the original logical connection wrapper.

connectionProperties

The connection properties that will be sent to the JDBC driver when establishing new connections

Format of the string must be [propertyName=property;]*

NOTE - The "user" and "password" properties will be passed explicitly, so they do not need to be included here.

initialSize

The default TransactionIsolation state of new connections.

If not set then the setTransactionIsolation method will not be called. The allowed values for this property are:

Note: Most JDBC drivers do not support all isolation levels DefaultTransactionIsolation The initial number of connections that are created when the pool is started

jtaManaged

Determines wether or not this data source should be JTA managed or user managed.

If set to 'true' it will automatically be enrolled in any ongoing transactions. Calling begin/commit/rollback or setAutoCommit on the datasource or connection will not be allowed. If you need to perform these functions yourself, set JtaManaged to false

In terms of JPA persistence.xml:

maxOpenPreparedStatements

The maximum number of open statements that can be allocated from the statement pool at the same time, or zero for no limit.

NOTE - Some drivers have limits on the number of open statements, so make sure there are some resources left for the other (non-prepared) statements.

poolPreparedStatements

If true, a statement pool is created for each Connection and PreparedStatements created by one of the following methods are pooled:

public PreparedStatement prepareStatement(String sql);
public PreparedStatement prepareStatement(String sql, int resultSetType, int resultSetConcurrency)

testOnBorrow

If true connections will be validated before being returned from the pool. If the validation fails, the connection is destroyed, and a new conection will be retrieved from the pool (and validated).

NOTE - for a true value to have any effect, the ValidationQuery parameter must be set.

testOnReturn

If true connections will be validated before being returned to the pool. If the validation fails, the connection is destroyed instead of being returned to the pool.

NOTE - for a true value to have any effect, the ValidationQuery parameter must be set.

testWhileIdle

If true connections will be validated by the idle connection evictor (if any). If the validation fails, the connection is destroyed and removed from the pool

NOTE - for a true value to have any effect, the timeBetweenEvictionRunsMillis property must be a positive number and the ValidationQuery parameter must be set.

XADataSource

There are several ways to configure a XADataSource. Depending the underlying datasource (Oracle, MySQL one or the other solution can be more adapted.

This part deals with JtaManaged XaDataSource since a not managed XaDataSource can be defined as a standard resource using class-name.

Single definition

First solution is to define as JdbcDriver an XADataSource:

<Resource id="myXaDs" type="DataSource">
    JdbcDriver = org.foo.MyXaDataSource

    myXaProperty = value

    myPoolProperty = 10
</Resource>

This solution merges properties for the XaDataSource and the pool (tomcat-jdbc for TomEE, dbcp for OpenEJB by default but still configurable with DataSourceCreator).

Note: in this case for Oracle for instance you'll define UserName for the pool and User for the datasource which can look weird if you don't know properties are used for 2 instances (pool and datasource).

Note: this solution uses the same logic than @DataSourceDefinition factory mecanism.

Two resources definition

An alternative is to define a resource for the XaDataSource:

<Resource id="myXa" class-name="org.foo.MyXaDataSource">
    myXaProperty = value
</Resource>

And then wrap it in the pool:

<Resource id="myXaDs" type="DataSource">
    DataSourceCreator = [dbcp|dbcp-alternative]
    myPoolProperty = 10
</Resource>

Note: dbcp is more adapted than dbcp-alternative in most of the case because it is reusing direct dbcp JTA management.

Known issues

For TomEE 1.7.0/1.7.1 you can need to add the property:

 openejb.datasource.pool = true

in resource properties to ensure the resource is pooled.

Details about DataSource and their factories (advanced configuration)

Configuration by creator