LISTS, STACKS, QUEUES, AND PRIORITY QUEUES - Introduction to Java Programming: Comprehensive Version - page 776

The output for list1 is [white, black, green, blue] . The copy method performs a
shallow copy: only the references of the elements from the source list are copied.
You can use the nCopies(int n, Object o) method to create an immutable list that
consists of n copies of the specified object. For example, the following code creates a list with
five Calendar objects.

nCopies

List<GregorianCalendar> list1 = Collections.nCopies
( 5 , new GregorianCalendar( 2005 , 0 , 1 ));

The list created from the nCopies method is immutable, so you cannot add, remove, or
update elements in the list. All the elements have the same references.
You can use the fill(List list, Object o) method to replace all the elements in the
list with the specified element. For example, the following code displays [black, black,
black] .

fill

List<String> list = Arrays.asList( "red" , "green" , "blue" );
Collections.fill(list, "black" );
System.out.println(list);

You can use the max and min methods for finding the maximum and minimum elements
in a collection. The elements must be comparable using the Comparable interface or the
Comparator interface. For example, the following code displays the largest and smallest
strings in a collection.

max and min methods

Collection<String> collection = Arrays.asList( "red" , "green" , "blue" );
System.out.println(Collections.max(collection));
System.out.println(Collections.min(collection));

The disjoint(collection1, collection2) method returns true if the two collections
have no elements in common. For example, in the following code, disjoint(collection1,
collection2) returns false , but disjoint(collection1, collection3) returns true .

disjoint method

Collection<String> collection1 = Arrays.asList( "red" , "cyan" );
Collection<String> collection2 = Arrays.asList( "red" , "blue" );
Collection<String> collection3 = Arrays.asList( "pink" , "tan" );
System.out.println(Collections.disjoint(collection1, collection2));
System.out.println(Collections.disjoint(collection1, collection3));

The frequency(collection, element) method finds the number of occurrences of the
element in the collection. For example, frequency(collection, "red") returns 2 in the
following code.

frequency method

Collection<String> collection = Arrays.asList( "red" , "cyan" , "red" );
System.out.println(Collections.frequency(collection, "red" ));

20.17

✓ ✓

Are all the methods in the Collections class static?

Check

20.18

Point

Which of the following static methods in the Collections class are for lists, and
which are for collections?

sort, binarySearch, reverse, shuffle, max, min, disjoint, frequency

20.19 Show the output of the following code:

import java.util.*;

public class Test {
public static void main(String[] args) {