java.util.Hashtable.putAll() Method

Description

The putAll(Map<? extends K,? extends V> t) method is used to copy all of the mappings from the specified Map to this Hashtable.

Declaration

Following is the declaration for java.util.Hashtable.putAll() method.

public void putAll(Map<? extends K,? extends V> t)

Parameters

• t--This is the mappings to be stored in this map.

Return Value

NA

Exception

• NullPointerException--This is thrown if the specified map is null.

Example

The following example shows the usage of java.util.Hashtable.putAll()

package com.tutorialspoint;

import java.util.*;

public class HashTableDemo {
   public static void main(String args[]) {
      // create hash table 
      Hashtable htable1 = new Hashtable(); 
      
      // create Map
      Map map=new HashMap();
      
      // put values in map
      map.put("1","TP");
      map.put("2","IS");
      map.put("3","BEST");
          
      System.out.println("Initial hash table value: "+htable1);
      System.out.println("Map values: "+map);
      
      // put map values in table
      htable1.putAll(map);
      System.out.println("Hash table value after put all: "+htable1);
   }    
}

Let us compile and run the above program, this will produce the following result.

Initial hash table value: {}
Map values: {3=BEST, 2=IS, 1=TP}
Hash table value after put all: {3=BEST, 2=IS, 1=TP}