info.archinnov.achilles.annotations

Annotation Type EntityCreator

@Retention(value=RUNTIME)
 @Target(value=CONSTRUCTOR)
 @Documented
public @interface EntityCreator

Define the custom constructor to be use to instantiate the entity. There should be maximum one non-default constructor annotated with @EntityCreator.

All the parameters of this custom constructor should:

• 1. have the same name as an existing mapped field
• 2. have the same Java type as an existing mapped field (for primitive types, we rely on autoboxing so you can use 'Long' or 'long' for example, it does not matter)

Please note that it is not mandatory to inject all mapped-fields in your custom constructor, some fields cat be set using setter or just let be null

If you wish to use different parameter name rather than sticking to the field name, you can declare manually all the field names matching the parameters using the fieldNames attribute

Example:

 @Table
 public class MyEntity {

     @PartitionKey
     private Long sensorId;

     @ClusteringColumn
     private Date date;

     @Column
     private Double value;

     //Correct custom constructor with matching field name and type
     @EntityCreator
     public MyEntity(Long sensorId, Date date, Double value) {
         this.sensorId = sensorId;
         this.date = date;
         this.value = value;
     }

     //Correct custom constructor with matching field name and type even if fewer parameters than existing field name
     @EntityCreator
     public MyEntity(Long sensorId, Date date) {
         this.sensorId = sensorId;
         this.date = date;
     }

     //Correct custom constructor with matching field name and autoboxed type (long)
     @EntityCreator
     public MyEntity(long sensorId, Date date, Double value) {
         this.sensorId = sensorId;
         this.date = date;
         this.value = value;
     }

     //Correct custom constructor with declared field name and type
     @EntityCreator({"sensorId", "date", "value"})
     public MyEntity(Long id, Date date, Double value) {
         this.sensorId = id;
         this.date = date;
         this.value = value;
     }

     //Incorrect custom constructor because non matching field name (myId)
     @EntityCreator
     public MyEntity(Long myId, Date date, Double value) {
         this.sensorId = myId;
         this.date = date;
         this.value = value;
     }

     //Incorrect custom constructor because field name not found (sensor_id)
     @EntityCreator({"sensor_id", "date", "value"})
     public MyEntity(Long sensor_id, Date date, Double value) {
         this.sensorId = sensor_id;
         this.date = date;
         this.value = value;
     }

     //Incorrect custom constructor because all field names are not declared (missing declaration of "value" in annotation)
     @EntityCreator({"sensorId", "date"})
     public MyEntity(Long sensor_id, Date date, Double value) {
         this.sensorId = sensor_id;
         this.date = date;
         this.value = value;
     }
 }
 

See Also:

@EntityCreator

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
String[]	value

Element Detail

value

public abstract String[] value

Default:

{}