apex-sort-sobs

Utility class that provides a short-hand method for sorting of Salesforce SObjects by any field. Uses a Quicksort implementation with Dynamic Type Inference.

usage

Sort on Field:

Account[] accs = [SELECT My_Custom_Field__c FROM Account LIMIT 2000];
SortSobs.ascending(accs, Account.My_Custom_Field__c);

Sort in reverse order (desc)

Account[] accs = [SELECT My_Custom_Field__c FROM Account LIMIT 2000];
SortSobs.descending(accs, Account.My_Custom_Field__c);

Sort on parent field:

List<Contact> entries = [SELECT Name, Account.Name FROM Contact LIMIT 2000];
SortSobs.ascending(entries, SObjectField[]{ Contact.Account, Account.Name });

When sorting on parent fields, the last item in the SObjectField array is always the field to sort on. All previous items must be relationship fields!

considerations

This implemenation is a little slower than a Comparable, mostly because of overhead in Type casting and we have to run an intial iteration to capture the values to sort.

todo

• Optimization around casting/general overhead
• Provide more complete benchmarking

benchmarking

n=2000

• built in List.sort() method 0.017s
• w/ custom comparable wrapper: 0.377s
• Hardcoded Quicksort: 0.435s
• Dynamic Field Quicksort: 0.692s
• Dynamic Field Quicksort on relationship (2 levels): 0.692s

Benchmark code for custom comparable wrapper for reference:

  public class ComparatorTest implements Comparable {
    public Account te;
    public ComparatorTest(Account te){
        this.te = te;
    }

    // Implement the compareTo() method
    public Integer compareTo(Object compareTo) {
        ComparatorTest compareToEmp = (ComparatorTest)compareTo;
        if (this.te.Name == compareToEmp.te.Name) return 0;
        if (this.te.Name > compareToEmp.te.Name) return 1;
        return -1;
    }
   }

License

MIT