Collections
11.Which of the following methods is used to get a synchronized version of a collection?
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A. Collections.synchronizedCollection()
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B. Collections.synchronizedMap()
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C. Collections.synchronizedList()
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D. All of the above
All of the above
All of the above
12.Which of the following collections allow duplicate values but not duplicate keys?
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A. HashSet
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B. ArrayList
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C. TreeMap
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D. HashMap
HashMap
HashMap
13.What will be the output of the following?
Map map = new LinkedHashMap<>();
map.put("A", "1");
map.put("B", "2");
map.put("A", "3");
System.out.println(map);
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A. {A=1, B=2, A=3}
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B. {B=2, A=3}
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C. {A=3, B=2}
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D. {A=1, B=2}
{A=3, B=2}
{A=3, B=2}