Getting Synchronized Map from Java HashMap

HashMap is a non synchronized collection class. If we want to perform thread-safe operations on it then we must have to synchronize it explicitly. In order to synchronize it explicitly the synchronizedMap() method of java.util.Collections class is used to return a synchronized (thread-safe) map backed by the specified map.

// Get synchronized map using Collections.synchronizedMap()

Map<Integer, String> synchrMap = Collections.synchronizedMap(hmap);

To iterate the synchronized map we use a synchronized block:

// Synchronized block
synchronized (synchrMap) {

      // Iterate synchronized map
      for (Map.Entry<Integer, String> entry : synchrMap.entrySet()) {

        // Print key : value
        System.out.println(entry.getKey() + " : " + entry.getValue());
        
      }
}

Implementation:

Synchronized Map : 
1 : Akshay
2 : Bina
3 : Chintu