private static boolean isNull(SmtExpr left,SmtExpr right,List<SmtExpr> others){
  if (left == null || right == null) {
    return true;
  }
  for (  SmtExpr smtExpr : others) {
    if (smtExpr == null) {
      return true;
    }
  }
  return false;
}

private static boolean isNull ( SmtExpr left , SmtExpr right , List < SmtExpr > others ) { if ( left == null || right == null ) { return true ; } for ( SmtExpr smtExpr : others ) { if ( smtExpr == null ) { return true ; } } return false ; }
returns true if any of the arguments is null
