Discriminator issue in inheritance mapping of Grails

I have 4 classes A, B, B1, B2 with inheritance mapping described as below:
A (mapped to table A) is the top-most parent class and its inheritance mapping strategy is tablePerHierarchy=false (means each of its sub-classes is mapped to a single table).
Class B extends from A, and B1, B2 extends from B. But B1 and B2 share the same table with B, so in B class, I declare tablePerHierarchy=true and a discriminator to separate B1 and B2.
The detail code is here:

class A {
     static mapping = {
          tablePerHierarchy false
          table 'A'
     }
}

class B extends A {
     static mapping = {
          tablePerHierarchy true
          table 'B'
          discriminator column : 'TYPE'
     }
     String bProp1
     String bProp2
}

class B1 extends B {
     static mapping = {
          discriminator column : 'TYPE', value : 'B1'
     }
     String b1Props1 
     String b1Props2
}

class B2 extends B {
     static mapping = {
          discriminator column : 'TYPE', value : 'B2'
     }
     String b2Props1
     String b2Props1
}

When I start my app, there's an error occured:

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'messageSource': Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManager': Cannot resolve reference to bean 'sessionFactory' while setting bean property 'sessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is org.hibernate.MappingException: No discriminator found for edu.test.B1. Discriminator is needed when 'single-table-per-hierarchy' is used and a class has subclasses
    at org.grails.tomcat.TomcatServer.start(TomcatServer.groovy:212)
    at grails.web.container.EmbeddableServer$start.call(Unknown Source)
    at _GrailsRun_groovy$_run_closure5_closure12.doCall(_GrailsRun_groovy:158)
    at _GrailsRun_groovy$_run_closure5_closure12.doCall(_GrailsRun_groovy)
    at _GrailsSettings_groovy$_run_closure10.doCall(_GrailsSettings_groovy:280)
    at _GrailsSettings_groovy$_run_closure10.call(_GrailsSettings_groovy)
    at _GrailsRun_groovy$_run_closure5.doCall(_GrailsRun_groovy:149)
    at _GrailsRun_groovy$_run_closure5.call(_GrailsRun_groovy)
    at _GrailsRun_groovy.runInline(_GrailsRun_groovy:116)
    at _GrailsRun_groovy.this$4$runInline(_GrailsRun_groovy)
    at _GrailsRun_groovy$_run_closure1.doCall(_GrailsRun_groovy:59)
    at RunApp$_run_closure1.doCall(RunApp:33)
    at gant.Gant$_dispatch_closure5.doCall(Gant.groovy:381)
    at gant.Gant$_dispatch_closure7.doCall(Gant.groovy:415)
    at gant.Gant$_dispatch_closure7.doCall(Gant.groovy)
    at gant.Gant.withBuildListeners(Gant.groovy:427)
    at gant.Gant.this$2$withBuildListeners(Gant.groovy)
    at gant.Gant$this$2$withBuildListeners.callCurrent(Unknown Source)
    at gant.Gant.dispatch(Gant.groovy:415)
    at gant.Gant.this$2$dispatch(Gant.groovy)
    at gant.Gant.invokeMethod(Gant.groovy)
    at gant.Gant.executeTargets(Gant.groovy:590)
    at gant.Gant.executeTargets(Gant.groovy:589)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManager': Cannot resolve reference to bean 'sessionFactory' while setting bean property 'sessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is org.hibernate.MappingException: No discriminator found for edu.test.B1. Discriminator is needed when 'single-table-per-hierarchy' is used and a class has subclasses
    ... 23 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is org.hibernate.MappingException: No discriminator found for edu.test.B1. Discriminator is needed when 'single-table-per-hierarchy' is used and a class has subclasses
    ... 23 more
Caused by: org.hibernate.MappingException: No discriminator found for edu.test.B1. Discriminator is needed when 'single-table-per-hierarchy' is used and a class has subclasses
    ... 23 more

I have followed the instruction of Grails documentation about discriminator ( http://grails.org/doc/latest/ref/Database%20Mapping/discriminator.html ) but it did not work. I have found a JIRA about this document issue here: http://jira.grails.org/browse/GRAILS-5168 and fixed my code as they comment but it still got the same error.

I do not know the reason which caused this issue. Does the tablePerHierarchy=true in B override that strategy defined in A?
Could you please help me to fix this problem? Thank you so much.

Recommended topics

Hot tags