13.2.1. About JPA
The Java Persistence API (JPA) is the standard for using persistence in Java projects. Java EE 6 applications use the Java Persistence 2.0 specification, documented here: http://www.jcp.org/en/jsr/detail?id=317.
Hibernate EntityManager implements the programming interfaces and life-cycle rules defined by the specification. It provides JBoss EAP 6 with a complete Java Persistence solution.JBoss EAP 6 is 100% compliant with the Java Persistence 2.0 specification. Hibernate also provides additional features to the specification.To get started with JPA and JBoss EAP 6, refer to the bean-validation, greeter, and kitchensink quickstarts: Section 1.4.1.1, “Access the Quickstarts”.
13.2.4. Configuration
13.2.4.1. Hibernate Configuration Properties
Table 13.1. Hibernate Java Properties
| Property Name | Description |
|---|---|
| hibernate.dialect | The classname of a Hibernate org.hibernate.dialect.Dialect. Allows Hibernate to generate SQL optimized for a particular relational database. In most cases Hibernate will be able to choose the correct org.hibernate.dialect.Dialect implementation, based on the JDBC metadata returned by the JDBC driver. |
| hibernate.show_sql | Boolean. Writes all SQL statements to console. This is an alternative to setting the log category org.hibernate.SQL to debug. |
| hibernate.format_sql | Boolean. Pretty print the SQL in the log and console. |
| hibernate.default_schema | Qualify unqualified table names with the given schema/tablespace in generated SQL. |
| hibernate.default_catalog | Qualifies unqualified table names with the given catalog in generated SQL. |
| hibernate.session_factory_name | The org.hibernate.SessionFactory will be automatically bound to this name in JNDI after it has been created. For example, jndi/composite/name. |
| hibernate.max_fetch_depth | Sets a maximum "depth" for the outer join fetch tree for single-ended associations (one-to-one, many-to-one). A 0 disables default outer join fetching. The recommended value is between 0 and 3. |
| hibernate.default_batch_fetch_size | Sets a default size for Hibernate batch fetching of associations. The recommended values are 4, 8, and 16. |
| hibernate.default_entity_mode | Sets a default mode for entity representation for all sessions opened from this SessionFactory. Values include: dynamic-map, dom4j, pojo. |
| hibernate.order_updates | Boolean. Forces Hibernate to order SQL updates by the primary key value of the items being updated. This will result in fewer transaction deadlocks in highly concurrent systems. |
| hibernate.generate_statistics | Boolean. If enabled, Hibernate will collect statistics useful for performance tuning. |
| hibernate.use_identifier_rollback | Boolean. If enabled, generated identifier properties will be reset to default values when objects are deleted. |
| hibernate.use_sql_comments | Boolean. If turned on, Hibernate will generate comments inside the SQL, for easier debugging. Default value is false. |
| hibernate.id.new_generator_mappings | Boolean. This property is relevant when using @GeneratedValue. It indicates whether or not the new IdentifierGenerator implementations are used for javax.persistence.GenerationType.AUTO, javax.persistence.GenerationType.TABLE and javax.persistence.GenerationType.SEQUENCE. Default value is true. |
| hibernate.ejb.naming_strategy | Chooses the org.hibernate.cfg.NamingStrategy implementation when using Hibernate EntityManager. This class is deprecated and this property is only provided for backward compatibility. This property must not be used with hibernate.ejb.naming_strategy_delegator. If the application does not use EntityManager, follow the instructions here to configure the NamingStrategy: . |
| hibernate.ejb.naming_strategy_delegator | Specifies an org.hibernate.cfg.naming.NamingStrategyDelegator implementation for database objects and schema elements when using Hibernate EntityManager. This property has the following possible values.
NOTE This property must not be used with hibernate.ejb.naming_strategy. It is a temporary replacement for org.hibernate.cfg.NamingStrategy to address its limitations. A more comprehensive solution is planned for Hibernate 5.0 that replaces both org.hibernate.cfg.NamingStrategy and org.hibernate.cfg.naming.NamingStrategyDelegator. If the application does not use EntityManager, follow the instructions here to configure the NamingStrategy: . |
IMPORTANT
For
hibernate.id.new_generator_mappings, new applications should keep the default value of true. Existing applications that used Hibernate 3.3.x may need to change it to false to continue using a sequence object or table based generator, and maintain backward compatibility. 13.2.4.2. Hibernate JDBC and Connection Properties
Table 13.2. Properties
| Property Name | Description |
|---|---|
| hibernate.jdbc.fetch_size | A non-zero value that determines the JDBC fetch size (calls Statement.setFetchSize()). |
| hibernate.jdbc.batch_size | A non-zero value enables use of JDBC2 batch updates by Hibernate. The recommended values are between 5 and 30. |
| hibernate.jdbc.batch_versioned_data | Boolean. Set this property to true if the JDBC driver returns correct row counts from executeBatch(). Hibernate will then use batched DML for automatically versioned data. Default value is to false. |
| hibernate.jdbc.factory_class | Select a custom org.hibernate.jdbc.Batcher. Most applications will not need this configuration property. |
| hibernate.jdbc.use_scrollable_resultset | Boolean. Enables use of JDBC2 scrollable resultsets by Hibernate. This property is only necessary when using user-supplied JDBC connections. Hibernate uses connection metadata otherwise. |
| hibernate.jdbc.use_streams_for_binary | Boolean. This is a system-level property. Use streams when writing/reading binary or serializable types to/from JDBC. |
| hibernate.jdbc.use_get_generated_keys | Boolean. Enables use of JDBC3 PreparedStatement.getGeneratedKeys() to retrieve natively generated keys after insert. Requires JDBC3+ driver and JRE1.4+. Set to false if JDBC driver has problems with the Hibernate identifier generators. By default, it tries to determine the driver capabilities using connection metadata. |
| hibernate.connection.provider_class | The classname of a custom org.hibernate.connection.ConnectionProviderwhich provides JDBC connections to Hibernate. |
| hibernate.connection.isolation | Sets the JDBC transaction isolation level. Check java.sql.Connection for meaningful values, but note that most databases do not support all isolation levels and some define additional, non-standard isolations. Standard values are 1, 2, 4, 8. |
| hibernate.connection.autocommit | Boolean. This property is not recommended for use. Enables autocommit for JDBC pooled connections. |
| hibernate.connection.release_mode | Specifies when Hibernate should release JDBC connections. By default, a JDBC connection is held until the session is explicitly closed or disconnected. The default value auto will choose after_statement for the JTA and CMT transaction strategies, and after_transaction for the JDBC transaction strategy. Available values are auto (default), on_close, after_transaction, after_statement. This setting only affects Session returned from SessionFactory.openSession. For Session obtained through SessionFactory.getCurrentSession, the CurrentSessionContext implementation configured for use controls the connection release mode for that Session. |
| hibernate.connection.<propertyName> | Pass the JDBC property <propertyName> to DriverManager.getConnection(). |
| hibernate.jndi.<propertyName> | Pass the property <propertyName> to the JNDI InitialContextFactory. |
13.2.4.3. Hibernate Cache Properties
Table 13.3. Properties
| Property Name | Description |
|---|---|
hibernate.cache.region.factory_class | The classname of a custom CacheProvider. |
hibernate.cache.use_minimal_puts | Boolean. Optimizes second-level cache operation to minimize writes, at the cost of more frequent reads. This setting is most useful for clustered caches and, in Hibernate3, is enabled by default for clustered cache implementations. |
hibernate.cache.use_query_cache | Boolean. Enables the query cache. Individual queries still have to be set cacheable. |
hibernate.cache.use_second_level_cache | Boolean. Used to completely disable the second level cache, which is enabled by default for classes that specify a <cache> mapping. |
hibernate.cache.query_cache_factory | The classname of a custom QueryCache interface. The default value is the built-in StandardQueryCache. |
hibernate.cache.region_prefix | A prefix to use for second-level cache region names. |
hibernate.cache.use_structured_entries | Boolean. Forces Hibernate to store data in the second-level cache in a more human-friendly format. |
hibernate.cache.default_cache_concurrency_strategy | Setting used to give the name of the default org.hibernate.annotations.CacheConcurrencyStrategy to use when either @Cacheable or @Cache is used. @Cache(strategy="..") is used to override this default. |
13.2.4.4. Hibernate Transaction Properties
Table 13.4. Properties
| Property Name | Description |
|---|---|
hibernate.transaction.factory_class | The classname of a TransactionFactory to use with Hibernate Transaction API. Defaults to JDBCTransactionFactory). |
jta.UserTransaction | A JNDI name used by JTATransactionFactory to obtain the JTA UserTransaction from the application server. |
hibernate.transaction.manager_lookup_class | The classname of a TransactionManagerLookup. It is required when JVM-level caching is enabled or when using hilo generator in a JTA environment. |
hibernate.transaction.flush_before_completion | Boolean. If enabled, the session will be automatically flushed during the before completion phase of the transaction. Built-in and automatic session context management is preferred. |
hibernate.transaction.auto_close_session | Boolean. If enabled, the session will be automatically closed during the after completion phase of the transaction. Built-in and automatic session context management is preferred. |
https://access.redhat.com/documentation/en-US/JBoss_Enterprise_Application_Platform/6.4/html/Development_Guide/sect-Java_Persistence_API_JPA.html