Copy map content to another hashmap in java

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We can use putAll() method to copy map content to another hashmap in java.

putAll(Map m): Puts all the entries from m into this map.

Syntax: 

public void putAll(Map m)

Example

package com.w3schools;
 
import java.util.HashMap;
 
public class Test {
  public static void main(String args[]){
	//Create HashMap object.
	HashMap<Integer, String> hashMap = new HashMap<Integer, String>();
 
	//Add objects to the HashSet.
	hashMap.put(4, "Roxy");
	hashMap.put(2, "Sunil");
	hashMap.put(5, "Sandy");
	hashMap.put(1, "Munish");
	hashMap.put(3, "Pardeep");
 	//Print the HashMap object.
	System.out.println("HashMap elements:");
	System.out.println(hashMap);
 
	//Create a sub map
	HashMap<Integer, String> subMap = new HashMap<Integer, String>();
	//Add elements
        subMap.put(6, "Ajay");
        subMap.put(7, "Vikas");
        hashMap.putAll(subMap);
 
        //Print the HashMap object.
      	System.out.println("HashMap elements:");
      	System.out.println(hashMap);
  }
}

Output

HashMap elements:
{1=Munish, 2=Sunil, 3=Pardeep, 4=Roxy, 5=Sandy}
HashMap elements:
{1=Munish, 2=Sunil, 3=Pardeep, 4=Roxy, 5=Sandy, 6=Ajay, 7=Vikas}