Navigation Operator for lookup field null check

Question

I am trying to use Navigation Operator. But not getting how to use it for this situation.

I want to do something like this

if ( Account != null && Account.xyz__c != null && Account.xyz__c.myField__c 
     != null) {
       // Do something
}

I am looking on docs. But everywhere I am finding this for 1 level.

Thanks in advance!

Answer 1

sObject field references have always acted as a Safe Navigation Operator (SNO):

Contact testContact = new Contact();
String accountOwnerName = testContact.Account.Owner.Name; // is null, not NullPointerException

If you need to use a non-sObject, you can chain the SNO indefinitely:

String result = source?.field1?.field2?.toLowerCase();

If at any point there would be a NullPointerException, you just get a null back.

In your example, assuming you didn't want to simply use the sObject "magic", you can:

if(Account?.xyz__r?.myField__c != null) {

But in reality, sObject references are safe until you try to call a method, so you can still just:

if(Account.xyz__r.myField__c != null) {

The most usual reason to use SNO is after deserializing JSON or XML and you're not sure intermediate objects may or may not be null.