There are two sets of properties that may be specified: those that are specific to openjpa and those that have been defined by the JPA specification. In some cases, two properties may be equivalent, but have different keys. For example, openjpa.LockTimeout and javax.persistence.lock.timeout are two different keys for the same property.
There are two methods that can be used to retrieve information related to properties:
getProperties() - This method provides a list of current properties. If a property has more than one key, the key that will be returned is the one that was used when the property was set. If the property was not explicitly set, the key defined by JPA specification will be returned with the default value.
getSupportedProperties() - This method returns a set of property keys. See the javadoc in the latest JPA specification for the definition of the set. If a property has more than one key, all possible keys will be returned.