CodeBuilder

Handler class:



public class LeadsTriggerHandler {
public static void createLead(List<Lead> lstLead)
{
     for( Lead ldcreate: lstLead)
    {

       if( ldcreate.Is_Doctor__c == True)
       {
          ldcreate.Salutation = 'Dr.';
       }
   }
}
}



trigger LeadsTrigger on Lead (before insert , before update) {

     LeadsTriggerHandler.createLead(Trigger.new);

}

Handler class:

public class ContactInsertHandler {
    public static void createContact()
    {
        Contact cont = new Contact();
        cont.LastName = 'Dharmik';
        insert cont;
    }
    
    private static boolean run = true;
    
    
    public static boolean runOnce(){
    
    if(run) {   
     run=false;
     return true;
    }
    else {
            return run;
      }
    }

}

Trigger:

Handler class:

public class CustomRollUp {
  
    
    public static void docount()
    {
        list<Opportunity> setopportunity = [ select Id, Name, Amount from Opportunity where 
StageName = 'Closed Won' and RecordTypeId = '0127F00000166iGQAQ' ];
        Double j = 0;
        for( Opportunity op : setopportunity)
        {
            
            j += op.Amount;
        }
   
        list<Fund__c> updaterecord = new list<Fund__c>();
         for (Fund__c f1 : [ select id from Fund__c ] )
        {
             f1.Total_opportunity_amount__c = j;
             updaterecord.add(f1);
        }
        
        update updaterecord;
    }
    
}


Trigger:

trigger CustomRollUp on Opportunity ( after insert , after update, after delete , after undelete) {
     CustomRollUp.docount();
}

Handler class:

Trigger:

trigger LimitTotalAmountInOpportunity on Opportunity (before insert) {

         LimitTotalAmountInOpportunityHandler.LimitAmount(Trigger.new);
}


Handler Class:
public class LimitTotalAmountInOpportunityHandler {
public static void LimitAmount(list<Opportunity> OpportunityList)
{
        double totalamount = 0;
       for(opportunity objopportunity : [select Amount from opportunity where createdDate = today                and createdById =: UserInfo.getUserId()]){
             if(objopportunity.amount != null)
                    totalamount += objopportunity.amount;
         }

for(opportunity objopportunity : OpportunityList){
      if(objopportunity.amount != null)
            totalamount += objopportunity.amount;
              if(totalAmount > 100000){
                  objopportunity.addError('Total Amount Limit Exceded');
              }
  }
}
}