7.1 Quick Start Guide - Reference Documentation
Authors: Graeme Rocher, Peter Ledbrook, Marc Palmer, Jeff Brown, Luke Daley, Burt Beckwith, Lari Hotari
Version: 3.1.6
Table of Contents
7.1 Quick Start Guide
A domain class can be created with the create-domain-class command:grails create-domain-class helloworld.Person
If no package is specified with the create-domain-class script, Grails automatically uses the application name as the package name.This will create a class at the location
grails-app/domain/helloworld/Person.groovy
such as the one below:package helloworldclass Person {
}
If you have the dbCreate
property set to "update", "create" or "create-drop" on your DataSource, Grails will automatically generate/modify the database tables for you.
You can customize the class by adding properties:class Person { String name Integer age Date lastVisit }
grails console
7.1.1 Basic CRUD
Try performing some basic CRUD (Create/Read/Update/Delete) operations.Create
To create a domain class use Map constructor to set its properties and call save:def p = new Person(name: "Fred", age: 40, lastVisit: new Date()) p.save()
Read
Grails transparently adds an implicitid
property to your domain class which you can use for retrieval:def p = Person.get(1) assert 1 == p.id
Person
object back from the database.
You can also load an object in a read-only state by using the read method:def p = Person.read(1)
def p = Person.load(1)
Update
To update an instance, change some properties and then call save again:def p = Person.get(1)
p.name = "Bob"
p.save()
Delete
To delete an instance use the delete method:def p = Person.get(1) p.delete()