如何创建只有一个数组的对象数组列表？ [英] How to create a List of Object arrays that has only one array?

问题描述

我有以下代码片段，我不明白为什么不工作：

I have the following code snippet, which I can't understand why doesn't work:

List<Object[]> listOfObjectArrays;
listOfObjectArrays = new ArrayList<>();
Object[] objectArray = new Object[] {1, "two", null};
listOfObjectArrays.add(objectArray);
// works just fine

listOfObjectArrays = Arrays.asList(objectArray, objectArray);
// works just fine

listOfObjectArrays = Arrays.asList(objectArray); // *
// compile error: Incompatible types. Required: List<java.lang.Object[]> Found: List<java.lang.Object>

listOfObjectArrays = Arrays.asList(new Object[] {1, "two", null});
// compile error: Incompatible types. Required: List<java.lang.Object[]> Found: List<java.lang.Object>

有人可以请我指向正确的方向吗？

Could somebody please point me in the right direction?

我已经看到 Jon Skeet的回答另一个问题，但最后一个例子对我没有效果。即使我在标有的行中向 Object 或 Object [] * 我得到一个编译错误。

I already saw Jon Skeet's answer on an other question, but the last example there does not work for me. Even if I add a cast to either Object or Object[] in the line marked with * I get a compile error.

推荐答案

Object [] 通过明确指定类型参数：

You can always tell Java that you want a list of Object[] by specifying the type parameter explicitly:

Object[] objectArray = { 1, "two", null };
List<Object[]> listOfObjectArrays = Arrays.<Object[]>asList(objectArray);

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