Grails GORM composition.

address.groovy

package gorm.composition.example.model

/**
 * @author zakir
 *
 * We'll use this class for our example of composition in GORM.
 * It will be embedded inside User domain class and will serve
 * as one of its properties.
 * Note: making modification to this class while the app
 * is running can cause program failure. The user/_form view
 * will fail to recognize the Address class' properties.
 */
class Address {
	String streetAddress
	String state
	String zipCode
	
	static constraints = {	
		streetAddress(blank:false)
		state(blank:false, inList:['AZ', 'NY', 'PA'])	
		zipCode(blank:false, matches:'[0-9]{5}')
	}
	
	/*
	 * We need this so that the address is properly displayed in views/user/show.gsp
	 */
	String toString() {
		"$streetAddress $state, $zipCode"
	}
}

form-after.gsp

<%@ page import="gorm.composition.example.User" %>
<%@ page import="gorm.composition.example.model.Address" %>

<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'userName', 'error')} required">
	<label for="userName">
		<g:message code="user.userName.label" default="User Name" />
		<span class="required-indicator">*</span>
	</label>
	<g:textField name="userName" required="" value="${userInstance?.userName}"/>
</div>

<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'firstName', 'error')} required">
	<label for="firstName">
		<g:message code="user.firstName.label" default="First Name" />
		<span class="required-indicator">*</span>
	</label>
	<g:textField name="firstName" required="" value="${userInstance?.firstName}"/>
</div>

<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'lastName', 'error')} required">
	<label for="lastName">
		<g:message code="user.lastName.label" default="Last Name" />
		<span class="required-indicator">*</span>
	</label>
	<g:textField name="lastName" required="" value="${userInstance?.lastName}"/>
</div>
<fieldset class="embedded"><legend><g:message code="user.homeAddress.label" default="Home Address" /></legend>
<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'homeAddress.state', 'error')} required">
	<label for="homeAddress.state">
		<g:message code="user.homeAddress.state.label" default="State" />
		<span class="required-indicator">*</span>
	</label>
	<g:select name="homeAddress.state" from="${Address.constraints.state.inList}" required="" value="${userInstance?.homeAddress?.state}" valueMessagePrefix="address.state"/>
</div>

<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'homeAddress.streetAddress', 'error')} required">
	<label for="homeAddress.streetAddress">
		<g:message code="user.homeAddress.streetAddress.label" default="Street Address" />
		<span class="required-indicator">*</span>
	</label>
	<g:textField name="homeAddress.streetAddress" required="" value="${userInstance?.homeAddress?.streetAddress}"/>
</div>

<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'homeAddress.zipCode', 'error')} required">
	<label for="homeAddress.zipCode">
		<g:message code="user.homeAddress.zipCode.label" default="Zip Code" />
		<span class="required-indicator">*</span>
	</label>
	<g:textField name="homeAddress.zipCode" pattern="${Address.constraints.zipCode.matches}" required="" value="${userInstance?.homeAddress?.zipCode}"/>
</div>
</fieldset>

form-before.gsp

<%@ page import="gorm.composition.example.User" %>


<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'userName', 'error')} required">
	<label for="userName">
		<g:message code="user.userName.label" default="User Name" />
		<span class="required-indicator">*</span>
	</label>
	<g:textField name="userName" required="" value="${userInstance?.userName}"/>
</div>

<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'firstName', 'error')} required">
	<label for="firstName">
		<g:message code="user.firstName.label" default="First Name" />
		<span class="required-indicator">*</span>
	</label>
	<g:textField name="firstName" required="" value="${userInstance?.firstName}"/>
</div>

<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'lastName', 'error')} required">
	<label for="lastName">
		<g:message code="user.lastName.label" default="Last Name" />
		<span class="required-indicator">*</span>
	</label>
	<g:textField name="lastName" required="" value="${userInstance?.lastName}"/>
</div>
<fieldset class="embedded"><legend><g:message code="user.homeAddress.label" default="Home Address" /></legend>
<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'homeAddress.state', 'error')} required">
	<label for="homeAddress.state">
		<g:message code="user.homeAddress.state.label" default="State" />
		<span class="required-indicator">*</span>
	</label>
	<g:select name="state" from="${addressInstance.constraints.state.inList}" required="" value="${addressInstance?.state}" valueMessagePrefix="address.state"/>
</div>

<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'homeAddress.streetAddress', 'error')} required">
	<label for="homeAddress.streetAddress">
		<g:message code="user.homeAddress.streetAddress.label" default="Street Address" />
		<span class="required-indicator">*</span>
	</label>
	<g:textField name="streetAddress" required="" value="${addressInstance?.streetAddress}"/>
</div>

<div class="fieldcontain ${hasErrors(bean: userInstance, field: 'homeAddress.zipCode', 'error')} required">
	<label for="homeAddress.zipCode">
		<g:message code="user.homeAddress.zipCode.label" default="Zip Code" />
		<span class="required-indicator">*</span>
	</label>
	<g:textField name="zipCode" pattern="${addressInstance.constraints.zipCode.matches}" required="" value="${addressInstance?.zipCode}"/>
</div>
</fieldset>

Gorm-Composition.markdown

These gists are used to showcase how GORM composition works.They are included in one of my blog posts (http://zakirtariverdiev.blogspot.com/2014/02/making-grails-gorm-composition-work.html). Repo with a complete working example can be found here on GitHub at this URL: https://github.com/zakirt/gorm-composition-example

user.groovy

package gorm.composition.example

import gorm.composition.example.model.Address

class User {
	String userName
	String firstName
	String lastName	
	Address homeAddress
	
    static constraints = {
		userName(blank:false, unique:true)
		firstName(blank:false)
		lastName(blank:false)
    }
		
	static embedded = ['homeAddress'] 
}