Package datomic

Interface Entity


  • public interface Entity
    Implements the Entity API for associative navigation by attribute keys. An Entity is lazy - the values of its attributes are not obtained from the db until get or touch are called, after which they are cached in the entity. Note that entities have reference-like equality semantics - Two entities are equal if they have the same id and their databases have the same id
    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      Database db()  
      java.lang.Object get​(java.lang.Object key)
      Gets the value of the attribute named by key, and is polymorphic on key type cardinality :many attributes will always return a collection, even when only one value
      java.util.Set<java.lang.String> keySet()  
      Entity touch()
      Touches all of the attributes of the entity, including any component entities recursively.
    • Method Detail

      • get

        java.lang.Object get​(java.lang.Object key)
        Gets the value of the attribute named by key, and is polymorphic on key type cardinality :many attributes will always return a collection, even when only one value
        Parameters:
        key - A colon-prefixed string, e.g. ":user/firstName"
        Returns:
        the value(s) of that attribute, or null if none
      • touch

        Entity touch()
        Touches all of the attributes of the entity, including any component entities recursively.
        Returns:
        this Entity
      • keySet

        java.util.Set<java.lang.String> keySet()
        Returns:
        the key names of the attributes
      • db

        Database db()
        Returns:
        the database value that is the basis for this entity