Given the code fragment:
public class Foo {
public static void main (String [ ] args) {
Map
unsortMap.put (10, "z");
unsortMap.put (5, "b");
unsortMap.put (1, "d");
unsortMap.put (7, "e");
unsortMap.put (50, "j");
Map
Comparator
@Override public int compare (Integer o1, Integer o2) {return o2.compareTo
(o2); } } );
treeMap.putAll (unsortMap);
for (Map.Entry
System.out.print (entry.getValue () + " ");
}
}
}
What is the result?
The code creates an unsorted HashMap with several key-value pairs and then transfers these entries into a TreeMap. The TreeMap uses a custom Comparator to sort its keys. The custom Comparator uses o2.compareTo(o1), which sorts the keys in descending order. Therefore, iterating through the TreeMap's entries will print the values corresponding to the keys sorted in descending order: 50, 10, 7, 5, 1. This results in the output: j z e b d.
Its B,tested with return o1.compareTo(o2).If you test it with return o2.compareTo(o2) answer is C.
I meant return o2.compareTo(o1) for answer C
a single z will be printed if with return o2.compareTo(o2); While a TreeMap cannot contain duplicate keys.
answer B: d b e z j tested; note the typo, it must be return o1.compareTo(o2);
C is correct as o2.compareTo(o1) sorts keys in descending order.
C is correct. Sort is DESC( I think this is a typo )
The answer is C. I believe there is a typo in compare method. The second o2 should be o1. Otherwise it only prints single z which makes no sense.