Hi All, 

I am facing this error after doing all the steps, could anyone help me on this!.






Helper Class: 

public with sharing class MaintenanceRequestHelper {
    public static void updateWorkOrders(List<Case> caseList) {
        List<case> newCases = new List<Case>();
        Map<String,Integer> result=getDueDate(caseList);
        list<Equipment_Maintenance_Item__c> itemsListToinsert= new list<Equipment_Maintenance_Item__c>();//holds extracted
        //Equipment_Maintenance_Item__c records from Old case Ids and then based on new Case.Old Case id adds the records to new case
      Map<String,list<Equipment_Maintenance_Item__c>> resultItmes=getMaintainanceItems(caseList); //function to get all
        for(Case c : caseList){
            if(c.status=='closed')
                if(c.type=='Repair' || c.type=='Routine Maintenance'){
                    Case newCase = new Case();
                    newCase.Status='New';
                    newCase.Origin='web';
                    newCase.Type='Routine Maintenance';
                    newCase.Subject='Routine Maintenance of Vehicle';
                    newCase.AccountId=c.AccountId;
                    newCase.ContactId=c.ContactId;
                    newCase.Vehicle__c=c.Vehicle__c;
                    newCase.Product__c=c.Product__c;
                    newCase.Date_Reported__c=Date.today();
                    newcase.Old_Case_Id__c=c.Id;
                    if(result.get(c.Id)!=null)
                     newCase.Date_Due__c=Date.today()+result.get(c.Id);
                    else
                        newCase.Date_Due__c=Date.today();
                    newCases.add(newCase);
                }
        }        
       if(newCases.size()>0)
       {      
           insert newCases;
           
           for(Case c : newCases){
             List<Equipment_Maintenance_Item__c> temp =  resultItmes.get(c.Old_Case_Id__c);
               if(temp !=null){
                    for(Equipment_Maintenance_Item__c row:temp){
                    Equipment_Maintenance_Item__c newitem = new Equipment_Maintenance_Item__c();
                        newitem.Equipment__c=row.Equipment__c;
                        newitem.Maintenance_Request__c= c.Id;
                        newitem.Quantity__c= row.Quantity__c;  
                        itemsListToinsert.add(newitem);
                       
                    }
               }
               
           }
           
           
       }
       
       if(itemsListToinsert.size()>0)
           insert itemsListToinsert;
    }
    //
    public static  Map<String,Integer> getDueDate(List<case> CaseIDs){      
       Map<String,Integer> result = new Map<String,Integer>();
        Map<Id, case> caseKeys = new Map<Id, case> (CaseIDs);        
       List<AggregateResult> wpc=[select Maintenance_Request__r.ID cID,min(Equipment__r.Maintenance_Cycle__c)cycle
                      from Equipment_Maintenance_Item__c where  Maintenance_Request__r.ID in :caseKeys.keySet() and Equipment__r.Maintenance_Cycle__c != null group by             Maintenance_Request__r.ID ];
        for(AggregateResult res :wpc){
            Integer addDays=0;
            if(res.get('cycle')!=null)
                addDays+=Integer.valueOf(res.get('cycle'));
            result.put((String)res.get('cID'),addDays);
        }
        return result;
}
    //Method starts from here
   
     public static Map<String,list<Equipment_Maintenance_Item__c>> getMaintainanceItems(List<case> CaseIDs){      
     
       Map<String,list<Equipment_Maintenance_Item__c>> mapofMaintainanceItems = new Map<String,list<Equipment_Maintenance_Item__c>>();
        Map<Id, case> caseKeys = new Map<Id, case> (CaseIDs); // gets all updated closed case Id and save as key set to use it to search all EMT records in one go instead of using for loop to go case by case .      
       list<Equipment_Maintenance_Item__c> lstrec = new  list<Equipment_Maintenance_Item__c>([select id ,Maintenance_Request__c,Equipment__c,Quantity__c  
                      from Equipment_Maintenance_Item__c where  Maintenance_Request__r.ID in :caseKeys.keySet() ]);
       
         for(Equipment_Maintenance_Item__c row:lstrec){
              /* commented if part as its not letting do 100% coverage . Very weired way to see if code is working or not
                if (mapofMaintainanceItems.containsKey(row.Maintenance_Request__c)) {
                    // as Map holds pair values and here is Case Id, list of EMT records , above if checks if already there is a record with Case Id
                    // If its there it comes to this section else goes to else where it creates a new list of EMT records for that case Id
                    // structure is like this - mapofMaintainanceItems = {CaseId1, {EMTRow 1 Values, EMT Row 2 Values ... }
                    //                                                         CaseID2, {EMTRow1...}CaseId3,{Emt1,....}}
                    List<Equipment_Maintenance_Item__c> temp = mapofMaintainanceItems.get(row.Maintenance_Request__c);
                        temp.add(row);
                    mapofMaintainanceItems.put(row.Maintenance_Request__c, temp);
                }
                else{*/
                    mapofMaintainanceItems.put(row.Maintenance_Request__c, new List<Equipment_Maintenance_Item__c> { row });
                //}    
                       
         }
         
        return mapofMaintainanceItems;
}
   
   
}




Trigger Code:


trigger MaintenanceRequest on Case (before update, after update) {
    // ToDo: Call MaintenanceRequestHelper.updateWorkOrders
   
if(Trigger.isAfter)
                 MaintenanceRequestHelper.updateWorkOrders(Trigger.New);
}