Package org.datanucleus.store.rdbms.mapping.java

Class ObjectMapping

  • All Implemented Interfaces:
    MappingCallbacks
    public class ObjectMapping
extends ReferenceMapping
    Mapping for Object fields. An Object field can represent two things
    1. An object of a series of possible PC types ("implementation-classes") and each implementation type is represented in the datastore by a FK to the PC table
    2. An object of a series of possible non-PC types (e.g String, Long, Double etc) and each implementation type is represented in the datastore by a separate column

    • Constructor Detail

      • ObjectMapping

        public ObjectMapping()

    • Method Detail

      • getJavaType

        public Class getJavaType()
        Description copied from class: JavaTypeMapping
        Accessor for the java type being mapped. This is the java type that the mapping represents. Some examples :
        • if the field is of type "MyClass" then the mapping will be OIDMapping (or subclass) the javaType will be OID, and the type will be MyClass.
        • if the field is of type "int" then the mapping will be IntegerMapping, the javaType will be Integer, and the type will be int.
        The "java type" is the java-type name used in the plugin.xml mapping file
        Overrides:
        getJavaType in class ReferenceMapping
        Returns:
        The java type

      • getJavaTypeForColumnMapping

        public String getJavaTypeForColumnMapping​(int index)
        Accessor for the name of the java-type actually used when mapping the particular datastore field. Returns Serializable since the object needs to be serialisable
        Overrides:
        getJavaTypeForColumnMapping in class ReferenceMapping
        Parameters:
        index - requested column index.
        Returns:
        the name of java-type for the requested column.