Question

Language: Java

Topic: HashMap, Sets, if - else statements

Question: How do you check if your Scanner input matches any of the objects in a HashMap?

For example, if you have

HashMap<String, String> hash = new HashMap<>();

The hash map includes String objects, with the key being names, and value being age number and their address.

if you ask for string name in scanner , how do you see if the hashmap contains this key given by user scanner. And then give the value of this key., if it exist in hashmap.

Answer 1

Program:

package collections;

import java.util.*;

public class HashMapQuestion {

public static void main(String[] args) {

Scanner in=new Scanner(System.in);

System.out.println("Enter name : ");

String name=in.nextLine();

int c=0;

HashMap<String,String> map=new HashMap<>();

map.put("Rahul","Age - 26 , Address - Preet Vihar");

map.put("Neha"," Age -22 , Address - Azad Nagar");

map.put("Roy"," Age -24 , Address - Lakshmi Nagar");

for(Map.Entry<String,String> m:map.entrySet()) {

if(m.getKey().equals(name+"")) {

c=1;

System.out.println("The Age and Address of ");

System.out.println(m.getKey()+" is : "+m.getValue());}}

if(c==0) {

System.out.println("Entry does not match! ");}

}

}

Output:

Enter name :

Neha

The Age and Address of

Neha is : Age -22 , Address - Azad Nagar