How to get key and value of HashMap in java.

How to get key and value of HashMap in java.

The HashMap extends AbstractMap and implements Map interface. It is available in java.util package. It stores value in the form of key/values pair. The put(key,value) method is used for adding entry in map.
entrySet()– It is a method of HashMap class.  Returns a Set of entries(Key/Value) of corresponding map.
getKey()– It is a method of Map.Entry interface. Returns key of corresponding entry.
getValue()– It is a method of Map.Entry interface. Returns value of corresponding entry.

Code: 
AccessKeyValueOfHashMap.java

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
public class AccessKeyValueOfHashMap {
       
public static void main(String[] args) {
               
// Create a Empty HashMap
               
HashMap<String, String> obHashMap = new HashMap<String, String>();
               
// Put values in hash map
                obHashMap
.put("AB", "1");
                obHashMap
.put("EF", "2");
                obHashMap
.put("Gh", "3");
                obHashMap
.put("CD", "4");
               
//Store entry (Key/Value)of HashMap in set
               
Set mapSet = (Set) obHashMap.entrySet();
               
//Create iterator on Set
               
Iterator mapIterator = mapSet.iterator();
               
System.out.println("Display the key/value of HashMap.");
               
while (mapIterator.hasNext()) {
                       
Map.Entry mapEntry = (Map.Entry) mapIterator.next();
                       
// getKey Method of HashMap access a key of map
                       
String keyValue = (String) mapEntry.getKey();
                       
//getValue method returns corresponding key's value
                       
String value = (String) mapEntry.getValue();
                       
System.out.println("Key : " + keyValue + "= Value : " + value);
               
}
       
}
}
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