Program: How to search a key in TreeMap?

Below example shows how to find out whether a specific key exists in the TreeMap or not. By using containsKey() method you can find out keys presence in the TreeMap.

package com.java2novice.treemap;

import java.util.TreeMap;

public class MyTreeMapKeySearch {
	
	public static void main(String a[]){
		TreeMap<String, String> hm = new TreeMap<String, String>();
		
		//add key-value pair to TreeMap
		hm.put("first", "FIRST INSERTED");
		hm.put("second", "SECOND INSERTED");
		hm.put("third","THIRD INSERTED");
		System.out.println(hm);
		if(hm.containsKey("first")){
			System.out.println("The TreeMap contains key first");
		} else {
			System.out.println("The TreeMap does not contains key first");
		}
		if(hm.containsKey("fifth")){
			System.out.println("The TreeMap contains key fifth");
		} else {
			System.out.println("The TreeMap does not contains key fifth");
		}
	}
}

{first=FIRST INSERTED, second=SECOND INSERTED, third=THIRD INSERTED}
The TreeMap contains key first
The TreeMap does not contains key fifth