Grails - when saving domain objects - i am getting "rejected value [null] error"
===

I have three domain objects defined as :

    class Member {
    	String name
    
    	static constraints = {}
    	static belongsTo=[community:Community]
    }
    
    class Community {
    	String leaderName
    	String code
    
    	static constraints = {}
    	static hasMany=[members: Member]
    	static belongsTo=[bank:Bank]
    }
    
    class Bank {
    
    	String bankName
    	static hasMany=[communities: Community]
    	static constraints = {}
    }


When I tried to initialize these domain objects with some test data in `BootStrap.groovy` config class as :

   

     def init = { servletContext ->
        
        		def m1 = new Member(name:"M1_Name")
        		def m2 = new Member(name:"M2_Name")
        		def m3 = new Member(name:"M3_Name")
        
        		m1.save(failOnError:true)
        		m2.save(failOnError:true)
        		m3.save(failOnError:true)
        
        		def comA = new Community(leaderName:"LeaderA", code:"AA")
        		def comB = new Community(leaderName:"LeaderB", code:"BB")
        
        		comA.addToMembers(m1)
        		comA.addToMembers(m2)
        		comB.addToMembers(m3)
        
        		comA.save(failOnError:true)
        		comB.save(failOnError:true)
        
        		def bankA = new Bank(name:"BankA")
        		def bankB = new Bank(name:"BankB")
        
        		bankA.addToCommunities(comA)
        		bankB.addToCommunities(comB)
        	}


I am getting following error :

    | Loading Grails 2.0.4
    | Configuring classpath.
    | Environment set to development.....
    | Packaging Grails application.....
    | Compiling 3 source files.....
    | Running Grails application
    | Error 2012-07-13 22:14:44,798 [pool-5-thread-1] ERROR context.GrailsContextLoader  - Error executing bootstraps: Validation Error(s) occurred during save():
    - Field error in object 'mygrailtests.Member' on field 'community': rejected value [null]; codes [mygrailtests.Member.community.nullable.error.mygrailtests.Member.community,mygrailtests.Member.community.nullable.error.community,mygrailtests.Member.community.nullable.error.mygrailtests.Community,mygrailtests.Member.community.nullable.error,member.community.nullable.error.mygrailtests.Member.community,member.community.nullable.error.community,member.community.nullable.error.mygrailtests.Community,member.community.nullable.error,mygrailtests.Member.community.nullable.mygrailtests.Member.community,mygrailtests.Member.community.nullable.community,mygrailtests.Member.community.nullable.mygrailtests.Community,mygrailtests.Member.community.nullable,member.community.nullable.mygrailtests.Member.community,member.community.nullable.community,member.community.nullable.mygrailtests.Community,member.community.nullable,nullable.mygrailtests.Member.community,nullable.community,nullable.mygrailtests.Community,nullable]; arguments [community,class mygrailtests.Member]; default message [Property [{0}] of class [{1}] cannot be null]
    
    Message: Validation Error(s) occurred during save():
    - Field error in object 'mygrailtests.Member' on field 'community': rejected value [null]; codes [mygrailtests.Member.community.nullable.error.mygrailtests.Member.community,mygrailtests.Member.community.nullable.error.community,mygrailtests.Member.community.nullable.error.mygrailtests.Community,mygrailtests.Member.community.nullable.error,member.community.nullable.error.mygrailtests.Member.community,member.community.nullable.error.community,member.community.nullable.error.mygrailtests.Community,member.community.nullable.error,mygrailtests.Member.community.nullable.mygrailtests.Member.community,mygrailtests.Member.community.nullable.community,mygrailtests.Member.community.nullable.mygrailtests.Community,mygrailtests.Member.community.nullable,member.community.nullable.mygrailtests.Member.community,member.community.nullable.community,member.community.nullable.mygrailtests.Community,member.community.nullable,nullable.mygrailtests.Member.community,nullable.community,nullable.mygrailtests.Community,nullable]; arguments [community,class mygrailtests.Member]; default message [Property [{0}] of class [{1}] cannot be null]
    
       Line | Method
    ->>  13 | doCall                           in BootStrap$_closure1
    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
    |   301 | evaluateEnvironmentSpecificBlock in grails.util.Environment
    |   294 | executeForEnvironment . . . . .  in     ''
    |   270 | executeForCurrentEnvironment     in     ''
    |   303 | innerRun . . . . . . . . . . . . in java.util.concurrent.FutureTask$Sync
    |   138 | run                              in java.util.concurrent.FutureTask
    |   886 | runTask . . . . . . . . . . . .  in java.util.concurrent.ThreadPoolExecutor$Worker
    |   908 | run                              in     ''
    ^   662 | run . . . . . . . . . . . . . .  in java.lang.Thread

Here, line 13 is 

    m1.save(failOnError:true)

Could you please suggest me what's wrong going on? Or what I am missing. 
