Grails域类失败

Question

The class is below:

package tsg

class Country {

    String code
    String codeShort
    String name
    String en
    String nl
    String de
    String fr
    String it
    String es

    static mapping = {
        id name: "code", generator: "assigned"
        version 'revision_number'
    }

    static constraints = {
        code maxSize: 4
        codeShort nullable: true, maxSize: 2
        name nullable: true, maxSize: 100
        en nullable: true, maxSize: 50
        nl nullable: true, maxSize: 50
        de nullable: true, maxSize: 50
        fr nullable: true, maxSize: 50
        it nullable: true, maxSize: 50
        es nullable: true, maxSize: 50
    }
}

And when I run 'grails run-app' I get:

| Error 2014-12-12 18:43:55,468 [localhost-startStop-1] ERROR context.GrailsContextLoaderListener  - Error initializing the application: Error creating bean with name 'transactionManagerPostProcessor': 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 java.lang.NullPointerException: Cannot invoke method call() on null object
Message: Error creating bean with name 'transactionManagerPostProcessor': 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 java.lang.NullPointerException: Cannot invoke method call() on null object
    Line | Method
->>  262 | run       in java.util.concurrent.FutureTask
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
|   1145 | runWorker in java.util.concurrent.ThreadPoolExecutor
|    615 | run . . . in java.util.concurrent.ThreadPoolExecutor$Worker
^    745 | run       in java.lang.Thread
Caused by BeanCreationException: Error creating bean with name 'transactionManager': Cannot resolve reference to bean 'sessionFactory' while setting bean property 'sessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is java.lang.NullPointerException: Cannot invoke method call() on null object
->>  262 | run       in java.util.concurrent.FutureTask
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
|   1145 | runWorker in java.util.concurrent.ThreadPoolExecutor
|    615 | run . . . in java.util.concurrent.ThreadPoolExecutor$Worker
^    745 | run       in java.lang.Thread
Caused by BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is java.lang.NullPointerException: Cannot invoke method call() on null object
->>  262 | run       in java.util.concurrent.FutureTask
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
|   1145 | runWorker in java.util.concurrent.ThreadPoolExecutor
|    615 | run . . . in java.util.concurrent.ThreadPoolExecutor$Worker
^    745 | run       in java.lang.Thread
Caused by NullPointerException: Cannot invoke method call() on null object
->>   25 | doCall    in tsg.Country$__clinit__closure2
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
|    262 | run       in java.util.concurrent.FutureTask
|   1145 | runWorker in java.util.concurrent.ThreadPoolExecutor
|    615 | run       in java.util.concurrent.ThreadPoolExecutor$Worker
^    745 | run . . . in java.lang.Thread
| Error Forked Grails VM exited with error

1. The funny thing is that, if instead the language name - en, fr, de, etc. I put something longer - lng_en, lng_fr, etc. it works.

2. If I take out the constrains for the languages fields, again, it works.

3. If I leave only the en constrain, it works.(the rest - nl, de, fr, it, es - are commented). I uncomment nl, run 'grails run-app' and it works. I uncomment de, run 'grails run-app' again and it works. But if I uncomment 2 fields at a time I get the same error. What could be the cause? Any ideas how to make it work (besides renaming the fields)?

Answer 1

Your problem is with the variable it . Inside of the closure it refers to the implicit optional argument to the constraints closure. You can get around that by naming the argument...

class Country {

    String code
    String codeShort
    String name
    String en
    String nl
    String de
    String fr
    String it
    String es

    static mapping = {
        id name: "code", generator: "assigned"
        version 'revision_number'
    }

    static constraints = { arg ->
        code maxSize: 4
        codeShort nullable: true, maxSize: 2
        name nullable: true, maxSize: 100
        en nullable: true, maxSize: 50
        nl nullable: true, maxSize: 50
        de nullable: true, maxSize: 50
        fr nullable: true, maxSize: 50
        it nullable: true, maxSize: 50
        es nullable: true, maxSize: 50
    }
}