How do you sort collection of StringBuffer object in java?

Problem statement: Given the collection of StringBuffer objects.
StringBuffer sb1 = new StringBuffer("Z");
StringBuffer sb2 = new StringBuffer("A");
StringBuffer sb3 = new StringBuffer("P");

You have to sort it either way, meaning natural order or custom order.

Answer:
// ASCENDING ORDER:

1. import java.util.Comparator;
2. import java.util.TreeSet;
3. public class Test {
4. public static void main(String[] args) {
5. SortStringBufferObject s = new SortStringBufferObject();
6. TreeSet<StringBuffer> t = new TreeSet<>(s);
7. t.add(new StringBuffer("Z"));
8. t.add(new StringBuffer("A"));
9. t.add(new StringBuffer("P"));
10. System.out.println(t);
11. }
12. }
13. class SortStringBufferObject implements Comparator<StringBuffer> {
14. public int compare(StringBuffer sb1, StringBuffer sb2) {
15. return sb1.toString().compareTo(sb2.toString());
16. }
17. }

Output:

[A, P, Z] 

// DESCENDING ORDER:

1. import java.util.Comparator;
2. import java.util.TreeSet;
3. public class Test {
4. public static void main(String[] args) {
5. SortStringBufferObject s = new SortStringBufferObject();
6. TreeSet<StringBuffer> t = new TreeSet<>(s);
7. t.add(new StringBuffer("Z"));
8. t.add(new StringBuffer("A"));
9. t.add(new StringBuffer("P"));
10. System.out.println(t);
11. }
12. }
13. class SortStringBufferObject implements Comparator<StringBuffer> {
14. public int compare(StringBuffer sb1, StringBuffer sb2) {
15. return sb2.toString().compareTo(sb1.toString());
16. }
17. }

Output:

[Z, P, A]
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