/*
Create Java Hashtable from HashMap example
This Java Example shows how to copy all key value pairs from HashMap Object to
Hashtable Object using putAll method of java Hashtable class.
*/
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.HashMap;
public class CreateHashtableFromHashMap {
public static void main(String[] args) {
//create HashMap
HashMap hMap = new HashMap();
//populate HashMap
hMap.put("1","One");
hMap.put("2","Two");
hMap.put("3","Three");
//create new Hashtable
Hashtable ht = new Hashtable();
//populate Hashtable
ht.put("1","This value would be REPLACED !!");
ht.put("4","Four");
//print values of Hashtable before copy from HashMap
System.out.println("Hashtable contents before copy");
Enumeration e = ht.elements();
while(e.hasMoreElements())
System.out.println(e.nextElement());
/*
To copy values from HashMap to Hashtable use
void putAll(Map m) method of Hashtable class.
Please note that this method will REPLACE existing mapping of
a key if any in the Hashtable
*/
ht.putAll(hMap);
//display contents of Hashtable
System.out.println("Hashtable contents after copy");
e = ht.elements();
while(e.hasMoreElements())
System.out.println(e.nextElement());
}
}
/*
Output would be
Hashtable contents before copy
Four
This value would be REPLACED !!
Hashtable contents after copy
Four
Three
Two
One
*/
