6.Which generic wildcard allows both read and write?
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A. <?>
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B. <T>
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C. <? extends T>
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D. T<?>
<T>
<T>
7.What is the purpose of <? extends T>?
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A. Accepts any superclass of T
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B. Accepts T only
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C. Accepts T and subclasses of T
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D. Doesn't allow null
Accepts T and subclasses of T
Accepts T and subclasses of T
8. What is the meaning of <? super T> in generics?
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A. Accepts any subclass of T
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B. Accepts only T
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C. Accepts T and any superclass
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D. Accepts only superclasses
Accepts T and any superclass
Accepts T and any superclass
9. Which of these operations is allowed on a List<? extends Number>?
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A. list.add(1);
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B. list.add(null);
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C. list.add(1.0);
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D. list.clear();
list.add(null);
list.add(null);