CodesJava

Easy learning with example program codes

how to copy map content to another hashtable?


Hashtable:

Hashtable extends Dictionary class and implements Map interface. It contains elements in key-value pair. It not allowed duplicate key. It is synchronized. It can’t contain null key or value. It uses hashcode() method for finding the position of the elements.

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

Example:

package com.codesjava;
 
import java.util.HashMap;
import java.util.Hashtable;
 
public class Test {
  public static void main(String args[]){
	//Create Hashtable object.
	Hashtable<String, String> hashtable = new Hashtable<String, String>();
	//Add objects to the Hashtable.
	hashtable.put("1", "Jai");
	hashtable.put("2", "Mahesh");
	hashtable.put("3","Vivek");
        System.out.println(hashtable);
        HashMap<String, String> hashMap = new HashMap<String, String>();
        hashMap.put("4", "Vishal");
        hashMap.put("5", "Hemant");
        hashtable.putAll(hashMap);
        System.out.println(hashtable);
  }
}

Output

{3=Vivek, 2=Mahesh, 1=Jai}
{5=Hemant, 4=Vishal, 3=Vivek, 2=Mahesh, 1=Jai}


Copyright © 2018 CodesJava DMCA.com Protection Status SiteMap