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How come, in Java, I can write List<?> list = new LinkedList<Double>(); but not List<Container<?>> list = new LinkedList<Container<Double>>(); where Container is just something like public class Container<T> { ... } This came up because I have a method that accepts a List<Container<?>> , and I would like to use Arrays.asList to pass arguments to it: process(Arrays.asList(new Container<Double>(), new Container<Double>())); But the language doesn't allow this, because it infers the type of Arrays.asList to be List<Container<Double>> , and that is not assignable to List<Container<?>> . If I add a String-parameterized Container to the call, process(Arrays.asList(new Container<Double>(), new Container<String>())); it still doesn't work, because it infers the type List<Container<? extends Serializable & Comparable<?>>> for Arrays.asList. Only if I pass in something that is neither Comparable nor Serializable does it work properly. Of course, I can put in a cast and get the compiler to shut up, but I'm wondering if I'm doing something wrong here.

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