Which statement is true?()
A.The time to find the value from HashMap with a Person key depends on the size of the map.
B.Deleting a Person key from a HashMap will delete all map entries for all keys of type Person.
C.Inserting a second Person object into a HashSet will cause the first Person object to be removed as a duplicate.
D.The time to determine whether a Person object is contained in a HashSet is constant and does NOT depend on the size of the map.
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What is the result?()
A.[1, 2, 3, 5]
B.[2, 1, 3, 5]
C.[2, 5, 3, 1]
D.[5, 3, 2, 1]
E.[1, 3, 5, 2]
F.Compilation fails.
G.An exception is thrown at runtime.
Which statement is true?()
A.Compilation fails because the hashCode method is not overridden.
B.A HashSet could contain multiple Person objects with the same name.
C.All Person objects will have the same hash code because the hashCode method is not overridden.
D.If a HashSet contains more than one Person object with name="Fred", then removing another Person, also with name="Fred", will remove them all.
What is the result?()
A.The code runs with no output.
B.An exception is thrown at runtime.
C.Compilation fails because of an error in line 20.
D.Compilation fails because of an error in line 21.
E.Compilation fails because of an error in line 23.
F.Compilation fails because of an error in line 25.
What is the result?()
A.3, 2, 1
B.1, 2, 3
C.Compilation fails.
D.The code runs with no output.
E.An exception is thrown at runtime.
What is the result?()
A.A,B,C
B.B,C,A
C.Compilation fails.
D.The code runs with no output
E.An exception is thrown at runtime.
What inserted at line 39, will sort the keys in the props HashMap?()
A.Arrays.sort(s);
B.s = new TreeSet(s);
C.Collections.sort(s);
D.s = new SortedSet(s);
What is the result?()
A.2,1,0
B.2,1,1
C.3,2,1
D.3,2,2
E.Compilation fails.
F.An exception is thrown at runtime.
Given that the elements of a PriorityQueue are ordered according to natural ordering, and:
What is the result?()
A.apple pear
B.banana pear
C.apple apple
D.apple banana
E.banana banana
Which three code fragments, inserted independently at line 6, will compile?()
A.list.add("foo");
B.Object o = list;
C.String s = list.get(0);
D.list = new ArrayList<String>();
E.list = new ArrayList<Object>();
Which two, inserted at line 11, will allow the code to compile?()
A.public class MinMax<?>{
B.public class MinMax<? extends Number>{
C.public class MinMax<N extends Object>{
D.public class MinMax<N extends Number>{
E.public class MinMax<? extends Object>{
F.public class MinMax<N extends Integer>{
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