Program: How to search a key in HashMap?

Below example shows how to find whether specified key exists or not. By using containsKey() method you can find out the key existance.

package com.java2novice.hashmap;

import java.util.HashMap;

public class MyHashMapKeySearch {
	
	public static void main(String a[]){
		HashMap<String, String> hm = new HashMap<String, String>();
		//add key-value pair to hashmap
		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 hashmap contains key first");
		} else {
			System.out.println("The hashmap does not contains key first");
		}
		if(hm.containsKey("fifth")){
			System.out.println("The hashmap contains key fifth");
		} else {
			System.out.println("The hashmap does not contains key fifth");
		}
	}
}

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