Java：为什么在调用 .readObject() 时，具有引用泛型类型的 ArrayList 不计为强制转换？
我正在从保存文件加载 ArrayList，该文件具有推断的泛型类型，但 eclpise 告诉我我还没有检查强制转换，为什么不 (ArrayList 算作强制转换吗？(TypeOfObject) 算作强制转换时，
game.evilSprites = (ArrayList<EvilSprite>) OIS.readObject();
将对象转换为邪恶精灵有效...
game.evilSprite = (EvilSprite) OIS.readObject();
编辑：太好了，谢谢，所以它至少是一个有效的转换，我如何检查它以删除警告？
I am loading an ArrayList from a save file which has a generic type inferred, but eclpise is telling me I haven't checked the cast, why doesn't (ArrayList< TypeOfObject >) count as a cast when (TypeOfObject) does?
game.evilSprites = (ArrayList<EvilSprite>) OIS.readObject();
casting the object as an evilSprite works...
game.evilSprite = (EvilSprite) OIS.readObject();
EDIT: great, thank you, so it is at least a valid cast, how do I check it to remove the warning?
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它确实算作强制转换，但无法正确检查。在执行时，由于类型擦除，对象没有关于它是否是
ArrayList、ArrayListIt does count as a cast, but it can't be checked properly. At execution time, an object has no information about whether it's an
ArrayList<String>, anArrayList<Object>etc, due to type erasure. So your cast is checking that it's anArrayListof some kind, but you could still get aClassCastExceptionwhen you try to fetch a sprite out of it - the values may not all beEvilSpritereferences.