Generic SObject update pattern

Question

Question

I know that it is possible to update a generic of List<SObject>, But what is the best approach to generate that list without knowing the SObjectType, only the ids ?

Sample:

 List<SObject> l = new List<SObject>();
 
 SObject o1 = new SObject(id='xxxxxx'); //this Id could be an Account
 o1.Name = 'Test';
 l.add(o1);


 SObject o2 = new SObject(id='xxxxxx'); //this Id could be a Custom
 o2.Name = 'Test' 
 l.add(o2); 
 
 //this is possible
 update l;

Unfortunately, SObject constructor doesn't allow id as parameter.

Backgound:

I'm trying to make a generic WS which will receive a list of objects to update( or upsert). The received object could by any type.

WS Request sample:

  [
   {id:'xxxxx',Name:'Test'},
   {id:'yyyyy',Name:'Test 2'},
   {id:'zzzzz',Name:'Test 3'}
  ]

The id attribute cloud be from any SObject.( I know the extra attr to update always exist).

Thanks in advance for your time.

Answer 1

Once you have the sObjectType you should be able to construct the sObject instance using the sObjectType.newSObject(ID Id) method. You can get the sObjectType from the Id using the Id.getSObjectType() method;

Map<Id, String> idsToUpdate = new Map<Id, String>();

// Put the Id's and associated name values in the map

List<SObject> sObjectsToUpdate = new List<SObject>();

for (Id idToUpdate : idsToUpdate.keySet()) {
    SObject o1 = idToUpdate.getSObjectType().newSObject(idToUpdate);
    // Set the Name field dynamically
    o1.put('Name', idsToUpdate.get(idToUpdate));
    sObjectsToUpdate.add(o1);
}

update sObjectsToUpdate;

Answer 2

Here's a link to a post that I think answers your question: Infering sObject Type from Id or collection of Id's

Essentially, the solution entails:

1. Pulling the sObject "prefix" (the first 3 characters) from the id you receive
2. Get the sObjectType so you can cast your objects as the corresponding sObject (or list<yourSobject__c>)
3. Upsert the typed-records

Link to SF Docs

---

Here's a Utility Method I wrote that writes a query to select ALL fields from an sObject by only giving the string value of the Object Name. It exemplifies finding an sObject's metadata (in this case, its fields).

public static string FormatFieldsForQuery(string objectName,string prefix){
    if(string.isNotBlank(prefix)){
        if(prefix.endsWith('__c'))
            prefix=prefix.replace('__c','__r.');   
        if(!prefix.endsWith('.'))
            prefix+='.';
    }
    string fields = '';
    sObjectType objectType=Schema.getGlobalDescribe().get(objectName);
    if(objectType==null)
        return fields;
    for(string f :objectType.getDescribe().fields.getMap().keySet())
        fields+=prefix+f+',';
    return fields.removeEnd(',');  
}//END FormatFieldsForQuery(string objectName,string prefix)