I recently inherited a Grails code base with a domain class called Name with (among others), the properties first and last to represent the first and last parts of a name, respectively. When writing a unit test which utilized this domain, I ran into some problems stemming from the names of these properties being the same as the first and last methods within Grails. Now, I can fix the problems by renaming the properties, but I was wondering if there is a way within Grails to use the property names first and last.
Namely, the error I was receiving was No signature of method: com.example.Name.first() is applicable for argument types: () values: []
Possible solutions: first(), first(java.lang.String), first(java.util.Map), list(), list(java.util.Map), print(java.lang.Object) when Grails attempts to apply a nullable: true constraint to the properties.
Here's the source of Name:
class Name {
String first
String middle
String last
static belongsTo = [person : Person]
static constraints = {
first(nullable:true)
middle(nullable:true)
last(nullable:true)
}
public static Name findOrCreate(String first, String middle, String last){
def name
name = Name.createCriteria().get{
and{
eq('first', first)
eq('middle', middle)
eq('last', last)
}
if(!name){
name = new Name()
name.first = first
name.middle = middle
name.last = last
}
return name
}
static mapping = {
cache true
}
}
You say that this error happens in the constraints block. In that case you may be able to get it working with an explicit delegate., i.e.
static constraints = {
delegate.first(nullable:true)
// and similarly for last
}
to force the first to be treated as a call into the constraints DSL rather than to the static GORM method.
Related
In my Grails project I need to add a particular constraint to an entry of my domain class object.
Domain class is as follows:
class HealthServiceType {
String healthService;
static belongsTo = [doctor:Doctor]
static constraints = {
}
static mapping = {
}
}
I need that healthService is not empty and is unique for each Doctor; that is, I can have multiple "test" value for healthService, but each one need to have different Doctor value.
Is it possible to perform this constraint in domain class? Or do I need to implement some check in Controller?
That's quite simple to make a unique property. For example:
static constraints = {
healthService(unique: ['doctor'])
}
The above will ensure that the value of healthService is unique for each value of doctor within your domain class.
I'm new to Grails. I'm developing a web app that handles the records of a gymnasium, to make routines, exercises, etc.
I have this domain class Ejercicios:
class Ejercicios {
String nombreEjercicio
String idHoja
String descripcion
List<String> descripcionO
static hasMany = [descripcionO: Descripciones]
static transients = ['descripcionTrans']
String descripcionTrans
static mapping = {
id column: "idHoja"
version false
}
static constraints = {
nombreEjercicio maxSize: 45
idHoja blank: false
}
The database table has the default Grails id named "idHoja", and another attribute named "id_hoja"
The thing here is that when I make a JSON parse from the rest API, I need GORM to look for exercises via the "id_hoja" attribute, not the "idHoja" because it'll cause a mismatch.
I found the solution by myself!
The only thing I needed to was to make the JSON call with the name "idHoja" and that was it.
Similar to my last question (Grails databinding: creating instances of an abstract class), I want to use data binding with a class that contains a collection of abstract classes with a hasMany relationship, but in this case, instead of using a List, I'm using a Map.
I created a smalll project with a failing integration test to show the problem that can be found in Github, run it with:
grails test-app -integration -echoOut DataBinding
Anyway, I'll explain the problem by describing the classes and the test here:
class LocalizableContent {
Map contentByLocale = [:].withDefault { locale -> new Text() }
static hasMany = [ contentByLocale : Content ]
}
abstract class Content {
static belongsTo = [ localizableContent : LocalizableContent ]
static constraints = {
localizableContent nullable:true
}
}
class Text extends Content {
String text
}
As you can see, I'm already using the withDefault trick, but apparently it's not being called by Grails / Spring (I even tried to throw an exception in the default closure to verify that the code is not executed).
For the sake of the test, I also created a LocalizableContentController which is empty. With all that, the following integration test then fails:
void testMapDatabinding() {
def rawParams = [ 'contentByLocale[en].text': 'Content' ]
def controller = new LocalizableContentController()
controller.request.addParameters(rawParams)
controller.request.setAttribute(GrailsApplicationAttributes.CONTROLLER, controller)
def localizableContent = new LocalizableContent(controller.params)
assert localizableContent?.contentByLocale['en']?.text == 'Content'
}
It says that localizableContent.contentByLocale is a map which looks like ['en': null], so apparently the data binding is understanding the map syntax and trying to create an entry for the 'en' key. But is not trying first to get the entry for that key, since the withDefault is not being called.
The following one tests that the withDefault works fine, and it passes:
void testMapByDefaultWithNoDatabinding() {
assert new LocalizableContent().contentByLocale['en']?.getClass() == Text
}
What am I missing here?
withDefault is nothing but a pattern to provide a valid value if you face an unknown key. For example, consider the below use case:
def map = [:].withDefault{k->
println k //Should print 'a'
10
}
map.test = 32
assert map.test == 32
assert map.a == 10
It takes the unknown key as the parameter, you cannot pass in any value to it, which is kind of logical, because it provides a default value instead of a value being provided.
In your case, the data binding would work if set the value to Text like:
Map contentByLocale = [:].withDefault { locale ->
//locale is the key. 'en' in this case
new Text(locale: locale, text: 'Content')
}
provided you have your Text class defined as
class Text extends Content{
String locale
String text
}
I'm creating a (theoretically) simple hasMany relationship within a domain class. I have two tables with a foreign key relationship between the two. Table 1's domain object is as follows:
Functionality{
String id
static hasMany = [functionalityControllers:FunctionalityController]
static mapping =
{
table 'schema.functionality'
id column:'FUNCTIONALITY_NAME', type:'string', generator:'assigned'
version false
}
}
and domain object 2
FunctionalityController
{
String id
String functionalityName
String controllerName
static mapping =
{
table 'schema.functionality_controller'
id column:'id', type:'string', generator:'assigned'
version:false
}
}
The issue I am having is that when I have the hasMany line inside of the Functionality domain object, the app won't start (both the app and the integration tests). The error is org.springframework.beans.factory.BeanCreationException leading to Invocation of init method failed; nested exception is java.lang.NullPointerException.
Any help would be appreciated.
UPDATE:
*Working Domains*:
class Functionality {
String id
static hasMany = [functionalityConts:FunctionalityCont]
static mapping =
{
table 'schema.functionality'
id column:'FUNCTIONALITY_NAME', type: 'string', generator: 'assigned'
functionalityConts( column:'functionality_name')
version false;
}
}
and
class FunctionalityCont {
String id
String functionalityName
String controllerName
static belongsTo = [functionality: Functionality]
static contraints = {
}
static mapping =
{
table 'schema.functionality_controller'
id column:'id', type: 'string', generator: 'assigned'
functionality(column:'FUNCTIONALITY_NAME')
version false;
}
}
Well 2 things...
1.I'm not sure but I guess that your domain class with the prefix 'Controller' maybe is the responsible, this is because grails is convention over configuration and by convention the controller class ends with Controller prefix and are in the controller folder, in this case is a lil' confusing
2.In GORM and in this case the relationship between objects can be unidirectional or bidirectional, is your decision to choose one, but in both cases there are different implementations, the class Functionality(btw is missing the 'class' word) has the right relationship to FunctionalityController through hasMany, but FunctionalityController doesn't knows about the relationship, so you can implement:
// For unidirectional
static belongsTo = Functionality
// For bidirectional
static belongsTo = [functionality:Functionality]
// Or put an instance of Functionality in your domain class,
// not common, and you manage the relationship
Functionality functionality
So check it out and tell us pls...
Regards
Try adding
static belongsTo = [functionality: Functionality]
to your FunctionalityController class. I suspect there is more to your error than what you've shown, but generally a hasMany needs an owning side to it. Since that is where the foreign key actually lives.
I've got a grails domain class I have to persist in Redis, something like this:
class A {
String one
Integer two
B three
E four
mapWith = "redis"
}
class B {
String name
}
enum E {
VALUE1, VALUE2
}
When I persist an instance of class A with the GORM .save() method, Redis saves it correctly except for the enum field "four".
As you can see the fact is known and reported here: http://jira.grails.org/browse/GPREDIS-3
Is there a good workaround to save Enum or something similar?
We're thinking about an array of String objects, what do you think?
I've got this mostly implemented but it doesn't work for Gemfire and I'm waiting until it's fixed for all the supported nosql providers before pushing the fix. As a workaround you can use the inList constraint with a combination of a persistent String property and a non-persistent get/set pair with the name of your current property, e.g.
class A {
String one
Integer two
B three
String fourString
void setFour(E e) {
fourString = e?.name()
}
E getFour() {
fourString ? E.valueOf(fourString) : null
}
static constraints = {
fourString inList: E.values()*.name()
}
static transients = ['fourString']
static mapWith = "redis"
}