如何在Grails 2.2中为Domain Class Values设置默认值？

Question

In my Grails domain class I want to set default values which do persist in the database. I use mysql as database. I tried to do this:

class A {

   long someValue = 1
   long someOtherValue
   boolean someBool = true
   boolean someOtherBool

   static mapping = {
      someOtherValue defaultValue: 1
      someOtherBool defaultValue: true  
   }
}

But nothing works. There are no default values set in the database. What do I have to change to get my default values being set correctly?

Answer 1

If you are on Grails 2.2 above then you can use defaultValue. Look at Burt's answer here Try it, hope this helps:

Class A {
      Long someValue 
      Long someOtherValue

      Boolean someBool
      Boolean someOtherBool

     static mapping = {
        someOtherValue defaultValue: 1
        someOtherBool  defaultValue: true  
        ...
     } 

}

Answer 2

I found that for defaultValue to work with String properties, I needed to put double quotes around single quotes and for defaultValue to work for numeric properties, I needed to put double quotes around the number or the defaults wouldn't appear in the DDL. So, for instance:

static mapping = {
   myStringProperty defaultValue: "'Cash'"
   myIntProperty defaultValue: "0"
}

Also, as far as I can tell, default values do not work for properties that are enums.

Answer 3

class A {

   long someValue
   long someOtherValue
   boolean someBool = Boolean.TRUE
   boolean someOtherBool = Boolean.TRUE

   static mapping = {
      someValue defaultValue: '1'
      someOtherValue defaultValue: '1'
   }
}

This will work, tested in 2.2.3.