com.holonplatform.jdbc.spring

Annotation Type EnableDataSource

@Target(value=TYPE)
 @Retention(value=RUNTIME)
 @Documented
 @Inherited
 @Import(value=DataSourceRegistrar.class)
public @interface EnableDataSource

Annotation to be used on Spring Configuration classes to setup a DataSource using external configuration properties according to DataSourceConfigProperties property names.

The actual DataSource implementation to be used can be specified using a symbolic type name, specified through the DataSourceConfigProperties.TYPE configuration property. By default, the following types are supported:

• com.holonplatform.jdbc.BasicDataSource: Create BasicDataSource instances, to be used typically for testing purposes. It is a simple DataSource implementation, using the DriverManager class and returning a new Connection from every getConnection call.
• com.zaxxer.hikari.HikariDataSource: Create HikariCP connection pooling DataSource instances. The HikariCP library dependency must be available in classpath. All default configuration properties are supported, and additional Hikari-specific configuration properties can be specified using the hikari prefix before the actual property name, for example: holon.datasource.hikari.connectionTimeout=50000
• org.apache.commons.dbcp2.BasicDataSource: Create DBCP2 connection pooling DataSource instances. The Apache Commons DBCP 2 library dependency must be available in classpath. All default configuration properties are supported, and additional DBCP-specific configuration properties can be specified using the dbcp prefix before the actual property name, for example: holon.datasource.dbcp.maxWaitMillis=3000
• org.apache.tomcat.jdbc.pool.DataSource: Create Tomcat JDBC connection pooling DataSource instances. The tomcat-jdbc library dependency must be available in classpath. All default configuration properties are supported, and additional Tomcat-specific configuration properties can be specified using the tomcat prefix before the actual property name, for example: holon.datasource.tomcat.maxAge=5000
• JNDI: Obtain a DataSource using JNDI. The jndi-name configuration property is required to specify the JNDI name to which the DataSource is bound in the JNDI context.

When the DataSourceConfigProperties.TYPE configuration property is not specified, the default DataSource type selection strategy is defined as follows:

1. If the HikariCP dependecy is present in classpath, the com.zaxxer.hikari.HikariDataSource type will be used;
2. If the Apache Commons DBCP2 dependecy is present in classpath, the org.apache.commons.dbcp2.BasicDataSource type will be used;
3. If the Tomcat JDBC dependecy is present in classpath, the org.apache.tomcat.jdbc.pool.DataSource type will be used;
4. Otherwise, the com.holonplatform.jdbc.BasicDataSource type is used as fallback

A data context id can be specified using dataContextId(), to discriminate configuration properties using given id as property prefix, and setting data context id as Spring bean qualifier to allow bean injection when multiple DataSource bean instances are registered in context, for example using Qualifier annotation.

When a data context id is specified, configuration properties must be written using that id as prefix, for example, if data context id is myid:
holon.datasource.myid.url=...

The DataSource bean is registered using DEFAULT_DATASOURCE_BEAN_NAME as bean name if no data context id is specified. Otherwise, bean name is composed using DEFAULT_DATASOURCE_BEAN_NAME, an underscore character and the data context id String, for example: dataSource_mydatacontextid.

In case of multiple DataSources, primary() or the external property SpringDataSourceConfigProperties.PRIMARY can be used to mark one of the DataSources as primary candidate for dependency injection when a qualifier is not specified.

Since:

5.0.0

Field Summary

Fields

Modifier and Type	Fields and Description
static String	DEFAULT_DATASOURCE_BEAN_NAME Default DataSource registration bean name.
static String	DEFAULT_TRANSACTIONMANAGER_BEAN_NAME Default PlatformTransactionManager registration bean name.

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
String	dataContextId Bind DataSource to given data context id.
boolean	enableTransactionManager Whether to register a JDBC PlatformTransactionManager to enable transactions management using Spring's transaction infrastructure, for example to enable Transactional annotations.
com.holonplatform.spring.PrimaryMode	primary Whether to qualify DataSource bean as primary, i.e.

Field Detail

DEFAULT_DATASOURCE_BEAN_NAME

public static final String DEFAULT_DATASOURCE_BEAN_NAME

Default DataSource registration bean name.

DEFAULT_TRANSACTIONMANAGER_BEAN_NAME

public static final String DEFAULT_TRANSACTIONMANAGER_BEAN_NAME

Default PlatformTransactionManager registration bean name.

Element Detail

dataContextId

public abstract String dataContextId

Bind DataSource to given data context id.

The data context id will be used as DataSource bean qualifier, allowing DataSources bean discrimination in case of multiple data context ids. You must ensure different data context ids are used when configuring multiple data sources using this annotation.

Returns:

Data context id

Default:

""

primary

public abstract com.holonplatform.spring.PrimaryMode primary

Whether to qualify DataSource bean as primary, i.e. the preferential bean to be injected in a single-valued dependency when multiple candidates are present.

When mode is PrimaryMode.AUTO, the registred DataSource bean is marked as primary or not according to the SpringDataSourceConfigProperties.PRIMARY configuration property, if present. If the property is not specified, the bean is not registered as primary by default.

Returns:

Primary mode, defaults to PrimaryMode.AUTO

Default:

com.holonplatform.spring.PrimaryMode.AUTO

enableTransactionManager

public abstract boolean enableTransactionManager

Whether to register a JDBC PlatformTransactionManager to enable transactions management using Spring's transaction infrastructure, for example to enable Transactional annotations.

Default is false.

Returns:

true to register a PlatformTransactionManager, false otherwise.

Default:

false