Kotlin使数据类的构造函数同时接受List和MutableList,但存储它们的可变实例 [英] Kotlin make constructor of data class accept both List and MutableList but store a mutable instance of them
问题描述
我想制作一个可以同时接受列表和可变列表的数据类,如果列表是MutableList的实例,则直接使其成为属性,如果它是List,则将其转换为MutableList,然后存储它。
I want to make a data class which can accept both list and mutable-list and if the list is instance of MutableList then directly make it a property else if it is a List then convert it into a MutableList and then store it.
data class SidebarCategory(val title: String, val groups: MutableList<SidebarGroup>) {
constructor(title: String, groups: List<SidebarGroup>) :
this(title, if (groups is MutableList<SidebarGroup>) groups else groups.toMutableList())
}
在上面的代码中,平台声明冲突:以下声明具有相同的JVM签名该类的辅助构造函数(第二行)抛出code>错误。
In the above code Platform declaration clash: The following declarations have the same JVM signature
error is thrown by the secondary constructor of the class (2nd line).
我该如何处理?我应该使用所谓的假构造函数(Companion.invoke())还是有更好的解决方法?
How should I approach this? Should I use a so called fake constructor (Companion.invoke()) or is there any better work-around?
推荐答案
List
和 MutableList
映射到相同的 java.util.List
类(映射类型),因此从JMV看起来像 SidebarCategory
具有两个相同的构造函数。
List
and MutableList
are mapped to the same java.util.List
class (mapped-types), so from JMV it will look like SidebarCategory
has two identical constructors.
您可以使用 Collection
代替 List
第二个构造函数。
Instead of List
, you can use Collection
in the second constructor.
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