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Java Program to retrieve the set of all keys in HashMap
First, create a HashMap and add elements
HashMap hm = new HashMap();
hm.put("Wallet", new Integer(700));
hm.put("Belt", new Integer(600));
hm.put("Backpack", new Integer(1200));Now, retrieve all the keys
Set keys = hm.keySet();
System.out.println("
Keys...");
Iterator i = keys.iterator();
while (i.hasNext()) {
System.out.println(i.next());
}The following is an example to get the set of all key in HashMap
Example
import java.util.*;
public class Demo {
public static void main(String args[]) {
// Create hash map
HashMap hm = new HashMap();
hm.put("Wallet", new Integer(700));
hm.put("Belt", new Integer(600));
hm.put("Backpack", new Integer(1200));
System.out.println("Map = "+hm);
Set keys = hm.keySet();
System.out.println("
Keys...");
Iterator i = keys.iterator();
while (i.hasNext()) {
System.out.println(i.next());
}
}
}The following is the output
Map = {Backpack=1200, Belt=600, Wallet=700}
Keys...
Backpack
Belt
Wallet
Updated on: 30-Jul-2019
194 Views
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