Iterate value through Java HashMap

Iterate through the values of Java HashMap example. This Java Example shows how to iterate through the values contained in the HashMap object.

In this tutorial, we are sharing an example of Iterate value through Java HashMap.

Following are the ways of traversing through a HashMap in Java programming language.

hm.entrySet() is used to retrieve all the key-value pairs called Map.Entries and stores internally into a set.
hm.entrySet().iterator() returns a iterator which acts as a cursor and points at the first element of the set and moves on till the end.
hmIterator.hasNext() checks for the next element in the set and returns a boolean
hmIterator.next() returns the next element(Map.Entry) from the set.
mapElement.getKey() returns the key of the associated Map.Entry
mapElement.getValue() return the value of the associated Map.Entry

Java HashMap program example

Copy the below program and execute to see the program output.

import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
 
public class IterateValuesOfHashMapExample {
public static void main(String[] args) {
 
//create HashMap object
HashMap hMap = new HashMap();
 
//add key value pairs to HashMap
hMap.put("1","One");
hMap.put("2","Two");
hMap.put("3","Three");
 
//get Collection of values contained in HashMap using Collection 
//values() method of HashMap class
Collection c = hMap.values();
 
//obtain an Iterator for Collection
Iterator itr = c.iterator();
 
//iterate through HashMap values iterator
while(itr.hasNext())
System.out.println(itr.next());
}
}

import java.util.Collection;

import java.util.HashMap;

import java.util.Iterator;

public class IterateValuesOfHashMapExample {

public static void main(String[] args) {

//create HashMap object

HashMap hMap = new HashMap();

//add key value pairs to HashMap

hMap.put("1","One");

hMap.put("2","Two");

hMap.put("3","Three");

//get Collection of values contained in HashMap using Collection

//values() method of HashMap class

Collection c = hMap.values();

//obtain an Iterator for Collection

Iterator itr = c.iterator();

//iterate through HashMap values iterator

while(itr.hasNext())

System.out.println(itr.next());

}

Output:

Three
Two
One

Java HashMap program example 2

// Import the HashMap class
import java.util.HashMap;

public class MyClass {
  public static void main(String[] args) {
    // Create a HashMap object called capitalCities
    HashMap<String, String> capitalCities = new HashMap<String, String>();

    // Add keys and values (Country, City)
    capitalCities.put("England", "London");
    capitalCities.put("Germany", "Berlin");
    capitalCities.put("Norway", "Oslo");
    capitalCities.put("USA", "Washington DC");
    System.out.println(capitalCities);
  }
}

// Import the HashMap class

import java.util.HashMap;

public class MyClass {

public static void main(String[] args) {

// Create a HashMap object called capitalCities

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

// Add keys and values (Country, City)

capitalCities.put("England", "London");

capitalCities.put("Germany", "Berlin");

capitalCities.put("Norway", "Oslo");

capitalCities.put("USA", "Washington DC");

System.out.println(capitalCities);

}

program output:

{USA=Washington DC, Norway=Oslo, England=London, Germany=Berlin}

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Iterate value through Java HashMap

Java HashMap program example

Java HashMap program example 2

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