Helper class for determining field change criteria

HelperTriggerUtility

public with sharing class HelperTriggerUtility {

    private SObject newObj;
    private SObject oldObj;

    public HelperTriggerUtility(SObject oldObj, SObject newObj) {
        this.newObj = newObj;
        this.oldObj = oldObj;
    }

    public Boolean hasFieldChanged(String fieldname)
    {
        if(oldObj.get(fieldname) != newObj.get(fieldname)){
            return true;
        } else {
            return false;
        }
    }

    public Boolean hasAnyFieldChanged(List<String> fieldnames)
    {
        for(String field : fieldnames){
            if(oldObj.get(field) != newObj.get(field)){
                return true;
            }
        }

        return false;
    }
}

Test_HelperTriggerUtility

@isTest
private class Test_HelperTriggerUtility {
    
    @isTest static void it_should_return_true_if_specified_field_changed() {
        Account oldAct = new Account();
        Account newAct = oldAct.clone();
        newAct.Name = 'New name';

        System.assert(oldAct.Name != newAct.Name);

        HelperTriggerUtility helper = new HelperTriggerUtility(oldAct, newAct);

        Boolean test = helper.hasFieldChanged('Name');

        System.assert(test, 'It should be true');
    }

    @isTest static void it_should_return_true_if_any_specified_field_is_changed() {
        Account oldAct = new Account();
        Account newAct = oldAct.clone();
        newAct.Name = 'New name';

        System.assertNotEquals(oldAct.Name,newAct.Name);

        HelperTriggerUtility helper = new HelperTriggerUtility(oldAct, newAct);

        List<String> posList = new List<String>{'Name','AnnualRevenue','Industry'};
        List<String> negList = new List<String>{'AnnualRevenue','Industry'};

        Boolean postive = helper.hasAnyFieldChanged(posList);
        Boolean negative = helper.hasAnyFieldChanged(negList);

        System.assert(postive, 'It should be true');
        System.assert(!negative, 'It should be false');
    }
    
}