用set记录excel是否有重复

    public String validateUniqueArray(String[] data, FieldHistory field) {        StringBuilder builder = new StringBuilder();         Set<String> set=new HashSet<String>();         int sumNull=0;         for(String str:data){             if (StringUtils.isBlank(str)) {                sumNull++;             }             set.add(str);         }         if(data.length>(set.size()+sumNull)){    //判断条件修改             builder.append(field.getName() + "列存在重复值,");         }        return builder.toString();    }