Question

我正在尝试创建一个在每个索引处都有字符串数组的Arraylist。我使用了以下代码：

ArrayList<String[]> deliveryTimes = new ArrayList<String[]>();
String[] str = new String[times.size()];//times is an Arraylist of string
for(int i=0; i<times.size();i++){
    str[i] = times.get(i);
}
deliveryTimes.add(str);

使用上面的代码，str数组的所有元素都在deliveryTimes arraylist中的不同索引处添加。但我想在索引处添加str作为数组。所以它应该如下：

[["a","b","c"],["aa","bb","cc"],["aaa","bbb","ccc"]]

但它就像：

["a","b","c","aa","bb","cc","aaa","bbb","ccc"]

Answer 1

....
String[] first = new String[]{"a", "b", "c"};
String[] second = new String[]{"aa", "bb", "cc"};
String[] third = new String[]{"aaa", "bbb", "ccc"};

addArrays(first, second, third);

...

ArrayList<ArrayList<String>> addArrays(String[]... strings) {
    ArrayList<ArrayList<String>> allTimes = new ArrayList<>(strings.length);

    for (String[] array : strings) {
        allTimes.add(new ArrayList<>(Arrays.asList(array)));
    }

    return allTimes;
}

allTimes包含：[[a，b，c]，[aa，bb，cc]，[aaa，bbb，ccc]]

Answer 2

您的deliveryTimes列表只包含一个String[]。将多个String[]添加到deliveryTimes列表。

ArrayList<String[]> deliveryTimes = new ArrayList<String[]>();

String[] one = new String[]{"a", "b", "c"};
String[] two = new String[]{"aa", "bb", "cc"};
String[] three = new String[]{"aaa", "bbb", "ccc"};

deliveryTimes.add(one);
deliveryTimes.add(two);
deliveryTimes.add(three);

for (String[] str : deliveryTimes) {
    System.out.println(Arrays.toString(str));
}

<强>输出

[a，b，c]

[aa，bb，cc]

[aaa，bbb，ccc]

您需要拆分时间列表并将它们分别添加到deliveryTimes列表。

创建数组的arraylist

2 个答案: