Bounded wilcard not working for List inserted in Map
The following code explains my problem:
interface f1 {}
interface f2 extends f1{}
1. List<? extends f1> l1 = new ArrayList<f2>();
2. Map<String, ? extends f1> m1 = new HashMap<String, f2>();
3. Map<String, List<? extends f1>> m2 = new Hash开发者_如何转开发Map<String, List<f2>>();
No. 1 and 2 work but no. 3 gives an error on eclipse. It says: Type mismatch: cannot convert from HashMap<String,List<f2>> to Map<String,List<? extends f1>>
Could you please help me figure out why.
Use
Map<String, ? extends List<? extends f1>> m2 = new HashMap<String, List<f2>>();
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