I would like to get the field names of a class and maybe store it in a list. Can anyone help? Thanks.
You can try this to get field names of domain class.
YourClass.declaredFields.each {
if (!it.synthetic) {
println it.name
}
}
You can use gormPersistentEntity for any domain object, this works with Grails 2.4.4 at least:
def names = Person.gormPersistentEntity.persistentPropertyNames
//returns ['firstName', 'lastName'...]
you can also get natural name using GrailsNameUtils like so:
def naturalNames = Person.gormPersistentEntity.persistentPropertyNames.collect {
grails.util.GrailsNameUtils.getNaturalName(it)
}
//returns ['First Name', 'Last Name'...]
def capitilizedNames = Person.gormPersistentEntity.persistentProperties.collect{
it.capitilizedName
}
//returns ['FirstName', 'LastName'...]
Just found it out, this one works:
def names = grailsApplication.getDomainClass('com.foo.Person').persistentProperties.collect { it.name }
You can iterate over the fields of a class like this.
YourClass.fields.each { println it.name }
If you need to put them into a list you could use collect() or populate it within the each.
http://groovy.codehaus.org/JN3535-Reflection
Related
I'm trying to get the list of a specific rental from the current user.
Code in controller:
def index() {
if (isLoggedIn()) {
String username = getPrincipal().username
def accountInstance = Account.findByUsername(username)
def rentalInstanceList = Rental.findAll("from Rental as r where r.account_id=:accountid", [accountid: accountInstance.id])
}
}
account_id is a foreign key.
After running I get the error:
could not resolve property: account_id of: ers.Rental
What am I doing wrong?
Generally, in HQL you have to use the field names as defined in your domain classes. So, your query should look like:
def list = Rental.findAll("from Rental where accountId=:accountid", [accountid: accountInstance.id])
or
def list = Rental.findAllByAccount accountInstance
or even
def list = Rental.findAllByAccount getPrincipal()
if the return type of getPrincipal() has the id field.
findAll is not limited to instances of the calling class so I use executeQuery instead. https://stackoverflow.com/a/8916483/5011228
I've been trying to take advantage of operator overloading in Groovy by defining a custom putAt method in my POGO like this:
class Book {
Map additionalInfo = [:]
def putAt(key, value) {
additionalInfo[key] = value
}
}
So that I can do something like, book['notes'] = 'I like this one.' (let's say this makes sense). However, I've been getting:
groovy.lang.MissingPropertyException: No such property: notes for class: Book
at BookSpec.Set property using putAt(BookSpec.groovy:40)
My class is part of a Grails application so I'm not sure if Grails has something to do with the problem. Can anyone enlighten me on this?
The signature should be
def putAt(String key, value)
Instead of doing putAt and then override the operator, there is an easy/better way by adding the propertyMissing methods.
Here is the link for more explanation.
class Foo {
def storage = [:]
def propertyMissing(String name, value) { storage[name] = value }
def propertyMissing(String name) { storage[name] }
}
def f = new Foo()
f.foo = "bar"
assertEquals "bar", f.foo
Is their a dynamic namedquery on grails? Im not sure if its the right term but, I mean a namedquery that can be true to all.
Something like:
namedQueries = {
dynamicQuery{ term, name, value ->
term(name, value)
}
}
Then it can be called maybe like but not exactly:
def testClass = TestClass.dynamicQuery('eq', 'lastname', 'Bill').list()
and so you call it too like:
def testClass = TestClass.dynamicQuery('gt', 'id', 12).list()
This one might not work but is their something similar in grails?
UPDATE
The idea is that so I can chained it as many as I want like:
def testClass = TestClass.dynamicQuery('gt', 'id', 12).dynamicQuery('eq', 'stat', 11).list()
This is so that I dont have to create many namedqueries. I was hoping I can create one and use it multiple times.
Grails' createCriteria method generates Grails HibernateCriteriaBuilder instance, within which you can call invokeMethod method to dynamically create query criteria, which usually is defined by the standard DSL.
Here is a example in some controller:
private String dynamicCriteriaTest(String term, name, value) {
def c = TestClass.createCriteria()
def param = []
param << name
param << value
def result = c.list{
c.invokeMethod(term, param as Object[])
}
return result.toString()
}
def test() {
render dynamicCriteriaTest('eq','lastname','Bill')
}
That will get something you want.
update
If you want to call this method multiple times, pass the criteria parameters in an a List then execute the query:
private List dynamicCriteriaTest(List param) {
def c = TestClass.createCriteria()
def paramList = param.collate(3) //split the parameters into groups
def result = c.list{
paramList.each { paramInstance ->
def command = paramInstance[0]
paramInstance.remove(0)
c.invokeMethod(command, paramInstance as Object[])
}
}
return result
}
def test() {
ArrayList param = new ArrayList()
//the 1st criteria
param << 'gt'
param << 'id'
param << (long)12 //you have to check the Grails [HibernateCriteriaBuilder] API to make sure the parameter passed to `invokeMethod` is in the right type (e.g. **long** in this case)
//the 2nd one
param << 'eq'
param << 'stat'
param << (long)11
//even more
param << 'like'
param << 'description'
param << 'some text%'
render dynamicCriteriaTest(param)
}
In Grails you have NamedQueries and also Where Queries. The example you give can possibly be implemented by using a namedqueries and placing this in a abstract domain class. Your domain classes should extend this abstract domain.
I'm trying to load data in a Grails application using the Fixture plugin.
class Author {
String name
}
class Book {
String title
hasMany = [authors:Author]
}
I load Author in a separate file and include it in the Book one.
//author fixture
fixture {
author1(Author) {
name = 'Ken Follett'
}
author2(Author) {
name = 'Martin Fowler'
}
}
//book fixture
fixture {
include 'author'
"book"(Book) {
title = 'Your favorite book'
authors = [author1, author2]
}
}
This all works fine. What I can't do, is to replace [author1, author2] so I can dynamically (and randomly) assign authors. Something like:
def dynamicallyBuiltAuthorList = "author1, author2, author100"
authors = ["${dynamicallyBuiltAuthorList}"]
Pretty much everything I tried so far gave me a no matching editors or conversion strategy found error.
Thanks in advance Grails gurus!
Based on your answer below (and the previous edit to this answer), this is probably a better way:
def dynamicallyBuiltAuthorList = [ 'author1', 'author2', 'author100' ].collect {
ref( "$it" )
}
authors = dynamicallyBuiltAuthorList
In the end the answer is simply:
def authorList = []
def dynamicallyBuiltAuthorList = [ 'author1', 'author2', 'author100' ].collect {
authorList.add(ref("$it"))
}
authors = authorList
Thanks to Tim for the help!
I'm working on a small event calendar and i want to sort the events by start time!
I'm using JodaTime Plugin in grails for the startTime attribute. ( http://www.grails.org/JodaTime+Plugin )
So, how can i sort with this datatype? This does not work:
def sortedEvents = events.asList().sort({ a, b -> a.startTime <=> b.startTime } as Comparator)
I hope you can help me!
Thanks,
whitenexx
/EDIT/
This is the code where i'm getting the events:
def getEventsNext(Location location) {
def events = location.events.findAll { it.endTime >= new DateTime() }
def sortedEvents = events.sort{it.startTime}
System.out.println(sortedEvents); //test
return sortedEvents
}
In /event/list action everything works fine with g:sortableColumn (sorting by startTime):
Try this:
def sortedEvents = events.asList().sort{it.startTime}
To reverse the sorting order, use:
def sortedEvents = events.asList().sort{-it.startTime}
FYI, Groovy adds this sort() method to Collection so you can remove asList() from the code above if events is already a Collection.
Try overriding the compareTo method in your domain classes.
For example,
int compareTo(obj) {
startTime.compareTo(obj.startTime)
}
Edit
Sort your events like so:
def sortedEvents = events.sort{e1,e2-> e1.startTime.compareTo(2.startTime)}
Or as suggested by #Don, the groovier equivalent
def sortedEvents = events.sort{e1,e2-> e1.startTime <=> e2.startTime}
Try
def events = location.events.findAll { it.endTime.isAfterNow() }
def sortedEvents = events.sort{it.startTime.toDate()}
JavaDoc for isAfterNow()