Package org.neo4j.ogm.annotation

Annotation Interface Properties

@Retention(RUNTIME) @Target(FIELD) @Inherited public @interface Properties
Tells OGM to map values of a Map field in a node or relationship entity to properties of a node or a relationship in the graph. The property names are derived from field name or prefix(), delimiter and keys in the Map. If the delimiter, prefix or keys conflict with other field names in the class the behaviour is not defined. Supported types for keys in the Map are String and Enum. The values in the Map can be of any Java type equivalent to Cypher types. Type derivation works best when you use concrete types in the declaration of the map (i.e. Map<String, Long> as we are able to use this information most of the time. In case you want Enum values, you must declare the composite property as Map<SUPPORTED_KEY_TYPE, YourEnumType>. Otherwise only writing, but not reading into an enum is supported. If allowCast() is set to true then types that can be cast to corresponding Cypher types are allowed as well.
Since:
3.0
Author:
Frantisek Hartman, Michael J. Simons

  • Element Details

    • prefix

      String prefix
      Allows for specifying a prefix for the map properties. OGM defaults to the field name of the map attribute when not set.
      Returns:
      The prefix for mapped properties.
      Default:
      ""

    • delimiter

      String delimiter
      Returns:
      Delimiter to use in the property names
      Default:
      "."

    • allowCast

      boolean allowCast
      Some Java types, like Integer and Float, can be automatically cast into a wider type, like Long and Double, by the Neo4j type systems. This in most cases not what one does expect during mapping. We have however not a way to determine whether the type of the value put into the map was supposed originally when reading the instance containing the map back. Set this attribute to true to allow OGM to accept the automatic cast.
      Returns:
      True, when the values of map entries are allowed to be cast to a wider datatype.
      Default:
      false

    • transformEnumKeysWith

      Class<? extends BiFunction<Properties.Phase,String,String>> transformEnumKeysWith
      This attribute allows for configuring a transformation that is applied to enum properties. Properties.Phase.TO_GRAPH is applied before the name of the enum is written to the graph, Properties.Phase.TO_ENTITY is applied before an instance of the enum value is referenced.
      Returns:
      A transformation to be used on enum keys.
      Default:
      org.neo4j.ogm.annotation.Properties.NoopTransformation.class