trigger handler framework

public abstract class TriggerHandler {

    public virtual void execute() {
        //please only uncomment the conditions below when needed for specific trigger contexts
        //this helps reduce the burden on those generating test classes
        if(Trigger.isBefore) {
            if(Trigger.isInsert)
                beforeInsert();
            else if(Trigger.isUpdate)
                beforeUpdate();
            //else if(Trigger.isDelete)
                //beforeDelete();
        }
        /*else if(Trigger.isAfter) {
            if(Trigger.isInsert)
                afterInsert();
            else if(Trigger.isUpdate)
                afterUpdate();
            else if(Trigger.isDelete)
                afterDelete();
            else if(Trigger.isUndelete)
                afterUndelete();
        }*/
        if(trigger.isAfter){
            if(trigger.isInsert){
                afterInsert();
            }
        }
    }

    //uncomment the below virtual classes as they're needed only
    public virtual void beforeInsert(){}
    public virtual void afterInsert(){}

    public virtual void beforeUpdate(){}
    //public virtual void afterUpdate(){}

    //public virtual void beforeDelete(){}
    //public virtual void afterDelete(){}

    //public virtual void afterUndelete(){}*/
}