The OpenJPA runtime includes a comprehensive system of configuration defaults and overrides:
OpenJPA first looks for an optional
OpenJPA searches for this resource in each top-level directory of your
CLASSPATH. OpenJPA will also find the resource if you place it within
META-INF directory in any top-level directory of the
contains property settings in
JPA's XML format.
You can customize the name or location of the above resource by specifying the
correct resource path in the
You can override any value defined in the above resource by setting the System property of the same name to the desired value.
In JPA, the values in the standard
bootstrapping file used by the
class at runtime override the values in the above resource, as well as
any System property settings. The
Map passed to
Persistence.createEntityManagerFactory at runtime also
overrides previous settings, including properties defined in
When using JCA deployment the
config-property values in your
ra.xml file override other settings.
All OpenJPA command-line tools accept flags that allow you to specify the configuration resource to use, and to override any property. Section 3, “ Command Line Configuration ” describes these flags.
Internally, the OpenJPA runtime environment and development
tools manipulate property settings through a general
Configuration interface, and in particular its
JDBCConfiguration subclasses. For advanced
customization, OpenJPA's extended runtime interfaces and its development tools
allow you to access these interfaces directly. See the
Javadoc for details.