Java Program to get Tail Map from TreeMap

Java 8Object Oriented ProgrammingProgramming

To get Tail Map from TreeMap, let us first create a TreeMap and set key-value pair −

TreeMap<String, String>tMap = new TreeMap<String, String>();
tMap.put("1", "A");
tMap.put("2", "B");
tMap.put("3", "C");
tMap.put("4", "D");
tMap.put("5", "E");
tMap.put("6", "F");
tMap.put("7", "G");

Now, let’s say you need to get the tailmap from 2 i.e. all the key-value pairs after 2. For that, use the method tailMap() −

SortedMapmap = tMap.tailMap("2");

Example

 Live Demo

import java.util.SortedMap;
import java.util.TreeMap;
public class Demo {
   public static void main(String[] args) {
      TreeMap<String, String>tMap = new TreeMap();
      tMap.put("1", "A");
      tMap.put("2", "B");
      tMap.put("3", "C");
      tMap.put("4", "D");
      tMap.put("5", "E");
      tMap.put("6", "F");
      tMap.put("7", "G");
      tMap.put("8", "H");
      tMap.put("9", "I");
      tMap.put("10", "J");
      SortedMap map = tMap.tailMap("2");
      System.out.println("Sub Map = " + map);
      map = tMap.tailMap("8");
      System.out.println("Sub Map = " + map);
      map = tMap.tailMap("1");
      System.out.println("Sub Map = " + map);
   }
}

Output

Sub Map = {2=B, 3=C, 4=D, 5=E, 6=F, 7=G, 8=H, 9=I}
Sub Map = {8=H, 9=I}
Sub Map = {1=A, 10=J, 2=B, 3=C, 4=D, 5=E, 6=F, 7=G, 8=H, 9=I}
raja
Published on 24-Apr-2019 09:07:25
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