To get subset from sorted set

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This tutorial explains how  to To get subset from sorted set.

To implement your own sorting functionality with TreeSet on user defined objects,

you have to pass Comparator object along with TreeSet constructor call.

The Comparator implementation holds the sorting logic.

Example

import java.util.Comparator;

import java.util.Set;

import java.util.TreeSet;

public class MySetSublist

{

   public static void main(String a[])

{         

       TreeSet<String> ts = new TreeSet<String>(new MyStrComp());

       ts.add("RED");

       ts.add("ORANGE");

       ts.add("BLUE");

       ts.add("GREEN");

       ts.add("WHITE");

       ts.add("BROWN");

       ts.add("YELLOW");

       ts.add("BLACK");

       System.out.println(ts);

       Set<String> subSet = ts.subSet("GREEN", "WHITE");

       System.out.println("sub set: "+subSet);

       subSet = ts.subSet("GREEN", true, "WHITE", true);

       System.out.println("sub set: "+subSet);

       subSet = ts.subSet("GREEN", false, "WHITE", true);

       System.out.println("sub set: "+subSet);

   }

}

class MyStrComp implements Comparator<String>

{

   @Override

   public int compare(String str1, String str2) {

       return str1.compareTo(str2);

   }     

}

Output

         [BLACK, BLUE, BROWN, GREEN, ORANGE, RED, WHITE, YELLOW]

        sub set: [GREEN, ORANGE, RED]

        sub set: [GREEN, ORANGE, RED, WHITE]

        sub set: [ORANGE, RED, WHITE]

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