Java 泛型问题 T extends Collections

[我是松哥]

public class MyGeneric <T extends Collections> {
T x;
MyGeneric(T x) {
this.x = x;
}
public static void main(String[] str) {
List<String> arrayList = new ArrayList<String>();
MyGeneric<?> test = new MyGeneric<List<String>>(arrayList); //此行出错，啥原因？
}
}

[I,Frankenstein]

你知道Collection 跟 Collections 的区别么？List 怎么会是Collections的子类呢？

[我是松哥]

Sorry, 知道原因了 Collections 应该是 Collection. public class MyGeneric <T extends Collection> { T x; MyGeneric(T x) { this.x = x; } public static void main(String[] str) { List<String> arrayList = new ArrayList<String>(); MyGeneric<?> test = new MyGeneric<List<String>>(arrayList); //ok } }

[我是松哥]

谢谢，很多没有用java,忘了:(