通用数组创建错误 [英] Generic array creation error

问题描述

我正在尝试做这样的事情:-

I am trying do something like this:-

public static ArrayList<myObject>[] a = new ArrayList<myObject>[2];

myObject 是一个类.我收到此错误:- 通用数组创建(箭头指向新的.)

myObject is a class. I am getting this error:- Generic array creation (arrow is pointing to new.)

推荐答案

您不能拥有泛型类的数组.Java 根本不支持它.

You can't have arrays of generic classes. Java simply doesn't support it.

您应该考虑使用集合而不是数组.例如，

You should consider using a collection instead of an array. For instance,

public static ArrayList<List<MyObject>> a = new ArrayList<List<MyObject>();

另一种解决方法"是创建一个像这样的辅助类

Another "workaround" is to create an auxilliary class like this

class MyObjectArrayList extends ArrayList<MyObject> { }

然后创建一个MyObjectArrayList的数组.

这是一篇关于为什么会这样的好文章不允许在该语言中.文章给出了以下示例，说明如果允许它会发生什么:

Here is a good article on why this is not allowed in the language. The article gives the following example of what could happen if it was allowed:

List<String>[] lsa = new List<String>[10]; // illegal
Object[] oa = lsa;  // OK because List<String> is a subtype of Object
List<Integer> li = new ArrayList<Integer>();
li.add(new Integer(3));
oa[0] = li; 
String s = lsa[0].get(0); 

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