relationship-model-generator
Introduction
When SObjects are queried in a single query, their parent-child __r fields are populated and can be used to navigate from one object to the other. But SOQL doesn’t allow a deep tree of objects to be queried in one go, and the collection __r fields are immutable.
This Visualforce page code generator produces an inner class per SObject that wraps the SObject and adds fields to model the parent and child relationships. Apex enums are created for the Record Types. Convenience methods are included to connect up parent or child objects and ensure that the relationship fields are set. A filtering mechanism is available for reads. Where an Id isn’t already known, a valid fake Id is generated so map logic keyed by Id can be used. Generic methods are provided so the relationships can be accessed by name, and the parent/child relationship names are also provided. A pure map form of the model - the mapified form - can be output for code that cannot be coupled to the model classes. A test class is also generated, primarily to ensure the generated code has test coverage.
Use this unchanged or clone and make your own changes. The code is generic - there are just a few default values tied to our specific objects. We are not looking for contributions, but rather just sharing some code that may be useful to others.
Screenshot
Sample code output
This is the first part of some code generated by this page that illustrates the resulting patterns:
/*
* Generated by the ModelGenerator page - do not edit directly.
*
* Simple type-safe SObject wrapper classes that hold the parent/child relationships
* to use in place of the __r properties (unusable in general as the collections are immutable).
* Adding a parent or a child also populates the reverse relationship.
* The SObject is exposed so its non-relationship fields can be directly accessed.
* Wrapper objects are created through factory methods so subclasses can be substituted in the future.
* A common interface is implemented by all wrapper classes.
* Enums are generated for record types.
* An optional filtering mechanism is available that is applied to reads.
* Every wrapper can offer an identify value in the form of a syntactically valid but sometimes fake Id.
* A "mapified" format of the data - nested Maps using the relationship names - can be generated.
*/
public inherited sharing class EligibilityModel {
//
// For problems
//
public class EligibilityModelException extends Exception {
}
//
// All wrappers implement this
//
public interface Wrapper {
// Return the wrapped SObject
SObject getSObject();
// Return the wrapped SObject type
SObjectType getSObjectType();
// Return the identity of the SObject (can be a fake Id value for non-persisted SObjects)
Id getId();
// Return the record type developer name or null if none
String getRecordTypeDeveloperName();
// Return a specific parent wrapper
Wrapper getParent(String relationshipName);
// Return a specific array of child wrappers
Wrapper[] getChildren(String relationshipName);
// Convert to form suitable for returning to external code without globals
Map<String, Object> mapify(Map<Id, Object> visited);
// Relationship names in both directions
Relationship[] getParentRelationships();
// Relationship names in both directions
Relationship[] getChildRelationships();
}
//
// Returned wrappers can have this filter applied
//
public interface Filter {
// Return true if the wrapped object should be returned
Boolean accept(Wrapper w);
}
//
// Filter that returns all objects and a single gamic instance of that filter
//
private class NoFilter implements Filter {
public Boolean accept(Wrapper w) {
// All
return true;
}
}
public static final Filter NO_FILTER = new NoFilter();
//
// Returned wrappers have this filter applied; intended for readers only
//
public static Filter filter {
get {
if (filter == null) filter = NO_FILTER;
return filter;
}
set;
}
//
// Generate a syntactically valid but fake Id
//
private static Integer nextFakeIdInteger = 0;
private static Id nextFakeId(SObjectType t) {
String RESERVED = '000';
String FAKE_TOKEN = 'FAKE';
String keyPrefix = t.getDescribe().getKeyPrefix();
String n = String.valueOf(nextFakeIdInteger++);
return keyPrefix + RESERVED + FAKE_TOKEN + '0'.repeat(15 - keyPrefix.length() - RESERVED.length() - FAKE_TOKEN.length() - n.length()) + n;
}
//
// Relationship names in both directions
//
public class Relationship {
String parent;
String rawParent;
String child;
String rawChild;
Relationship(String parent, String rawParent, String child, String rawChild) {
this.parent = parent;
this.rawParent = rawParent;
this.child = child;
this.rawChild = rawChild;
}
}
//
// Claim
//
// Factory method
public static Claim newClaim(Claim__c sob) {
Claim w = new Claim();
w.sob = sob;
return w;
}
// Wrapper class
public class Claim implements Wrapper {
// Wrapped object
public Claim__c sob {get; private set;}
// Either the SObject Id or a temporary fake Id
private Id transientId;
// Any name
public String recordTypeDeveloperName {get; private set;}
// Parent wrapper object relationships
public ContactWrapper claimantInsured {
get {
return filter.accept(claimantInsured) ? claimantInsured : null;
}
private set;
}
public Policy policy {
get {
return filter.accept(policy) ? policy : null;
}
private set;
}
// Child wrapper object relationships
public BenefitClaimed[] benefitClaimeds {
get {
if (benefitClaimeds == null) benefitClaimeds = new BenefitClaimed[] {};
if (filter === NO_FILTER) {
// Returns the modifiable collection
return benefitClaimeds;
} else {
// Returns a new collection
BenefitClaimed[] ws = new BenefitClaimed[] {};
for (BenefitClaimed w : benefitClaimeds) {
if (filter.accept(w)) ws.add(w);
}
return ws;
}
}
private set;
}
public ClaimRelationship[] claimRelationships {
get {
if (claimRelationships == null) claimRelationships = new ClaimRelationship[] {};
if (filter === NO_FILTER) {
// Returns the modifiable collection
return claimRelationships;
} else {
// Returns a new collection
ClaimRelationship[] ws = new ClaimRelationship[] {};
for (ClaimRelationship w : claimRelationships) {
if (filter.accept(w)) ws.add(w);
}
return ws;
}
}
private set;
}
public Journal[] journals {
get {
if (journals == null) journals = new Journal[] {};
if (filter === NO_FILTER) {
// Returns the modifiable collection
return journals;
} else {
// Returns a new collection
Journal[] ws = new Journal[] {};
for (Journal w : journals) {
if (filter.accept(w)) ws.add(w);
}
return ws;
}
}
private set;
}
public PaymentSpecification[] paymentSpecifications {
get {
if (paymentSpecifications == null) paymentSpecifications = new PaymentSpecification[] {};
if (filter === NO_FILTER) {
// Returns the modifiable collection
return paymentSpecifications;
} else {
// Returns a new collection
PaymentSpecification[] ws = new PaymentSpecification[] {};
for (PaymentSpecification w : paymentSpecifications) {
if (filter.accept(w)) ws.add(w);
}
return ws;
}
}
private set;
}
// Create via factory method only
private Claim() {
}
// Wrapper interface methods
public SObject getSObject() {
return sob;
}
public SObjectType getSObjectType() {
return sob.getSObjectType();
}
public Id getId() {
if (transientId == null) {
transientId = sob.Id != null ? sob.Id : nextFakeId(Claim__c.SObjectType);
}
return transientId;
}
public String getRecordTypeDeveloperName() {
return recordTypeDeveloperName;
}
public Wrapper getParent(String relationshipName) {
switch on relationshipName {
when 'claimantInsured' { return claimantInsured; }
when 'policy' { return policy; }
when else { throw new EligibilityModelException('Bad parent relationshipName ' + relationshipName); }
}
}
public Wrapper[] getChildren(String relationshipName) {
switch on relationshipName {
when 'benefitClaimeds' { return benefitClaimeds; }
when 'claimRelationships' { return claimRelationships; }
when 'journals' { return journals; }
when 'paymentSpecifications' { return paymentSpecifications; }
when else { throw new EligibilityModelException('Bad children relationshipName ' + relationshipName); }
}
}
public Relationship[] getParentRelationships() {
return new Relationship[] {
new Relationship('claimantInsured', 'cve__ClaimantInsured__r', 'claims', 'cve__Claims__r'),
new Relationship('policy', 'cve__Policy__r', 'claims', 'cve__Claims__r')
};
}
public Relationship[] getChildRelationships() {
return new Relationship[] {
new Relationship('claim', 'cve__Claim__r', 'benefitClaimeds', 'cve__BenefitClaimeds__r'),
new Relationship('claim', 'cve__Claim__r', 'claimRelationships', 'cve__ClaimRelationships__r'),
new Relationship('claim', 'cve__Claim__r', 'journals', 'cve__Journals__r'),
new Relationship('claim', 'cve__Claim__r', 'paymentSpecifications', 'cve__PaymentSpecifications__r')
};
}
public Map<String, Object> mapify(Map<Id, Object> visited) {
return mapify(this, visited);
}
// Any name
public String setRecordTypeDeveloperName(String name) {
recordTypeDeveloperName = name;
return recordTypeDeveloperName;
}
// Parent object methods
public ContactWrapper setParentClaimantInsured(Contact sob) {
ContactWrapper w = sob != null ? newContactWrapper(sob) : null;
claimantInsured = w;
if (w != null) w.claims.add(this);
return w;
}
public Policy setParentPolicy(Policy__c sob) {
Policy w = sob != null ? newPolicy(sob) : null;
policy = w;
if (w != null) w.claims.add(this);
return w;
}
// Child object methods
public BenefitClaimed addChildToBenefitClaimeds(BenefitClaimed__c sob) {
if (sob == null) return null;
BenefitClaimed w = newBenefitClaimed(sob);
benefitClaimeds.add(w);
w.claim = this;
return w;
}
public ClaimRelationship addChildToClaimRelationships(ClaimRelationship__c sob) {
if (sob == null) return null;
ClaimRelationship w = newClaimRelationship(sob);
claimRelationships.add(w);
w.claim = this;
return w;
}
public Journal addChildToJournals(Journal__c sob) {
if (sob == null) return null;
Journal w = newJournal(sob);
journals.add(w);
w.claim = this;
return w;
}
public PaymentSpecification addChildToPaymentSpecifications(PaymentSpecification__c sob) {
if (sob == null) return null;
PaymentSpecification w = newPaymentSpecification(sob);
paymentSpecifications.add(w);
w.claim = this;
return w;
}
}
...
Sample test output
/*
* Generated by the ModelGenerator page - do not edit directly.
*
* Cover the generated code.
*/
@IsTest
private class EligibilityModelTest {
@IsTest
static void claim() {
EligibilityModel.Claim w = EligibilityModel.newClaim(new Claim__c());
System.assertNotEquals(null, w.setParentClaimantInsured(new Contact()));
System.assertNotEquals(null, w.setParentPolicy(new Policy__c()));
System.assertNotEquals(null, w.addChildToBenefitClaimeds(new BenefitClaimed__c()));
System.assertNotEquals(null, w.addChildToClaimRelationships(new ClaimRelationship__c()));
System.assertNotEquals(null, w.addChildToJournals(new Journal__c()));
System.assertNotEquals(null, w.addChildToPaymentSpecifications(new PaymentSpecification__c()));
// Any value
System.assertEquals('Abc123', w.setRecordTypeDeveloperName('Abc123'));
}
@IsTest
static void benefitClaimed() {
EligibilityModel.BenefitClaimed w = EligibilityModel.newBenefitClaimed(new BenefitClaimed__c());
System.assertNotEquals(null, w.setParentClaim(new Claim__c()));
System.assertNotEquals(null, w.setParentBenefit(new Benefit__c()));
System.assertNotEquals(null, w.setParentLatestJournal(new Journal__c()));
System.assertNotEquals(null, w.setParentLatestPaymentSpecification(new PaymentSpecification__c()));
System.assertNotEquals(null, w.setParentPolicy(new Policy__c()));
System.assertNotEquals(null, w.addChildToCoveragesClaimed(new CoverageClaimed__c()));
System.assertNotEquals(null, w.addChildToJournals(new Journal__c()));
System.assertNotEquals(null, w.addChildToPaymentSpecifications(new PaymentSpecification__c()));
// Enum wrapper method
System.assertEquals(EligibilityModel.BenefitClaimedRecordType.Accident, w.setRecordType('Accident'));
// Enum static method
System.assertEquals(EligibilityModel.BenefitClaimedRecordType.WholeLife, EligibilityModel.BenefitClaimed.toBenefitClaimedRecordType('WholeLife'));
// Non-enum value
System.assertEquals(null, w.setRecordType('Abc123'));
System.assertEquals('Abc123', w.recordTypeDeveloperName);
}
...