java - 当我删除 List> 中特定索引处的元素时出现 UnsupportedOperationException？

Question

我有List<List<String>>这样的数据，

List<List<String>> repdata = [
    ["1185","R","4t","G","06","L","GT","04309","2546","2015","CF FE","01H1","20","23840","FF20"],
    ["1192","R","11t","H","06","L","SA","04772","8345","2015","BZ C8 FE","01D6","13","33390","LC13"]]

我想特别删除内部列表中索引 14 处的值。

例如:在此内部列表数据中

[["1185","R","4t","G","06","L","GT","04309","2546","2015","CF FE","01H1","20","23840","FF20"]]

我想删除 FF20，

并且必须对 List<List<String>> repdata 中的所有内部列表重复此操作。 .

所以，我的最后List<List<String>>会是这样的，

List<List<String>> repdata = [
["1185","R","4t","G","06","L","GT","04309","2546","2015","CF FE","01H1","FF20","23840"],
["1192","R","11t","H","06","L","SA","04772","8345","2015","BZ C8 FE","01D6","13","33390"]

其实这个List<List<String>> repdata is = criteria.list()从 hibernate 。这是这样转换的，

criteria.setResultTransformer(Transformers.TO_LIST);

我厌倦了这样删除，

List<List<String>> repdata = cr.list();
        for( List<String> list: repdata ){
            if( list.size() > 14){                              
                list.remove(14);
            }           
        }

但我不断得到UnsupportedOperationException .

有人可以帮我解决这个问题吗？

Answer 1

虽然我没有足够的信息，但我怀疑返回的列表可能是固定大小的(或以其他方式不可修改)。一个例子是我们从 Arrays.asList 获取的列表，它无法添加/删除任何内容。我们无法从结构上修改此列表。

解决方案可能是使用当前列表中的项目来初始化列表实现。 LinkedList 支持更快的删除并且可能合适。像这样的东西:

List<String> list = new LinkedList<String>(Arrays.asList(your_list));

如果符合您的要求，您也可以使用ArrayList。