How to list down all Standard/Custom Objects and ignore System(Internal) Objects

Question

There's always a requirement to pull ALL standard and custom objects using describe call ignoring all system/internal objects. Is there a way for same?

One of option is to reference ProcessInstance object (ie ApprovalProcess enabled objects)

for(Schema.SObjectType item : ProcessInstance.TargetObjectId.getDescribe().getReferenceTo()) { ..} 

I was successfully using this approach in my appexchange app code, however these lines don't work (are not supported) in PE org as PE doesn't support approval process by default.

I have been through this post How to find only those Schema.SObjectType types that are visible in the Schema Builder but that too doesn't have a definite/100% solution to list down (almost) ALL standard and custom objects (and ignore system objects)? I think Andrew's response does help to certain level.

Any work around to fetch ALL standard and custom objects (and ignore system/internal objects)?

UPDATE (11 Dec, 14) Posted an Idea on IdeaExchange. Please Vote Idea Add isSystemObject() in GetDescribe to indicate if an object is System/Internal

Answer 1

Though not 100% an answer, but based on various posts and comments (like one from @Andrew), below is a solution which will give you a list of all standard and custom objects ignoring system objects:

public List<SelectOption> getStandardCustomIgnoreSytemObjects() {

  List<SelectOption> options = new List<SelectOption>();
  for (Schema.SObjectType item1: Schema.getGlobalDescribe().values())
  {
    String name = item1.getDescribe().getName();
    // Exclude all the unwanted Sobjects e.g. CustomSettings, 
    // History, Share, Feed, ApexClass, Pages etc.
    if (!item1.getDescribe().isCustomSetting() 
        && item1.getDescribe().getRecordTypeInfos().size() > 0 
        && item1.getDescribe().isCreateable() 
        && !name.containsignorecase('history') 
        && !name.containsignorecase('tag') 
        && !name.containsignorecase('share') 
        && !name.containsignorecase('feed')) {
         options.add(new SelectOption(item1.getDescribe().getName(),
                                      item1.getDescribe().getLabel()));
        }
  }
  options.add(new SelectOption('Asset', 'Asset')); 
  // Asset doesn't come up, so explicitly add the same.
  options.sort();
}

Answer 2

You can get the list from the following SOQL:

SELECT SObjectType From ObjectPermissions Group By SObjectType

This basically gets you all objects for which you can assign permissions in a Profile.