java - Hibernate Composite Key Join -


i'm trying use spring data perform joined queries 1 of tables has composite key , i'm not sure how map entities.

here analogy of data model:

table: device pk=model_id pk=serial_id ...  table: device_settings pk=device_settings_id fk=model_id fk=serial_id ...

here analogy of code, doesn't compile due "mappedby" attribute isn't present.

@entity @table(name = "device_settings") public class devicesettings {      @id     @generatedvalue(strategy = generationtype.auto)     @column(name = "device_settings_id")     private long id;      // pretty sure problem     @onetomany(targetentity = device.class, mappedby = "devicekey", cascade = {cascadetype.merge}, fetch = fetchtype.eager)     @joincolumns({         @joincolumn(name = "model_id", referencedcolumnname = "model_id"),         @joincolumn(name = "serial_id", referencedcolumnname = "serial_id")})     private list<device> devices; }  @entity @table(name = "device") public class device {     @id         private devicekey devicekey;     }     ... }   @embeddable public class devicekey implements serializable {     private static final long serialversionuid = -1943684511893963184l;      @column(name = "model_id")     private long modelid;      @column(name = "serial_id")     private short serialid; }

associations marked mappedby must not define database mappings @jointable or @joincolumn

to achieve scenario have define @manytoone: 

@manytoone(cascade = {cascadetype.merge}, fetch = fetchtype.eager)     @joincolumns({         @joincolumn(name = "model_id", referencedcolumnname = "model_id"),         @joincolumn(name = "serial_id", referencedcolumnname = "serial_id")})      private device device;

this end model_id, serial_id, device_settings_id

or

define @joincolumn in device entity entities:

devicesettings : 

    @entity     @table(name = "device_settings")     public class devicesettings {          @id         @generatedvalue(strategy = generationtype.auto)         @column(name = "device_settings_id")         private long id;           @onetomany( mappedby = "devicesettings", cascade = {cascadetype.merge}, fetch = fetchtype.eager)          private list<device> devices; }

device entity : 

@entity @table(name = "device") public class device {          @embeddedid         private devicekey devicekey;          @manytoone         @joincolumn(name="device_settings_id")         private devicesettings devicesettings;        //getters , setters }

note : can decide owner of relationship , put mappings accorindly either 1 device has many device settings or other way around.


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