Object creation
Spring Data automatically tries to detect a persistent entity’s constructor to be used to materialize objects of that type. The resolution algorithm works as follows:
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If there’s a no-argument constructor, it will be used. Other constructors will be ignored.
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If there’s a single constructor taking arguments, it will be used.
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If there are multiple constructors taking arguments, the one to be used by Spring Data will have to be annotated with
@PersistenceConstructor
.
The value resolution assumes constructor argument names to match the property names of the entity, i.e. the resolution will be performed as if the property was to be populated, including all customizations in mapping (different datastore column or field name etc.).
This also requires either parameter names information available in the class file or an @ConstructorProperties
annotation being present on the constructor.
The value resolution can be customized by using Spring Framework’s @Value
value annotation using a store-specific SpEL expression.
Please consult the section on store specific mappings for further details.