转自:https://blog.csdn.net/zwhfyy/article/details/45562589

    //根据长度生成字段名集合,A-Z...
    public static List<String> getColumnList(int length){
        List<String> list = new ArrayList<>();
        for (int i = 0; i < length; i++) {
            String column = getKey(i);
            list.add(column);
        }
        return list;
    }

    //java 实现生成excel表头，A-Z;AA-ZZ;AAA-ZZZ支持无限
    public static String getKey(int index){
        String colCode = "";
        char key='A';
        int loop = index / 26;
        if(loop>0){
            colCode += getKey(loop-1);
        }
        key = (char) (key+index%26);
        colCode += key;
        return colCode;
    }

    //测试
    public static void main(String[] args) throws IOException {
        String key = getKey(26);
        System.out.println(key);
        List<String> columnList = getColumnList(26);
        System.out.println(columnList);
    }

    输出:
          AA
          [A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z]