Java Hashtable elements() Method

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Description

The Java Hashtable elements() method is used to return an enumeration of the values in this hashtable.

Declaration

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

public Enumeration<V> elements()

Parameters

NA

Return Value

The method call returns an enumeration of the values in this hashtable.

Exception

NA

Getting Enumeration of Values of a HashTable of Integer, Integer Pair Example

The following example shows the usage of Java Hashtable elements() method to iterate over the values of a Hashtable using Enumeration. We've created a Hashtable object of Integer,Integer pairs. Then few entries are added. An enumeration is retrieved using elements() method and then it is iterated to print the values of the hashtable.

package com.tutorialspoint;

import java.util.Enumeration;
import java.util.Hashtable;

public class HashtableDemo {
   public static void main(String args[]) {
      
      // create hash table
      Hashtable<Integer,Integer> hashtable = new Hashtable<>();

      // populate hash table
      hashtable.put(1, 1);
      hashtable.put(2, 2);
      hashtable.put(3, 3); 

      Enumeration<Integer> enumeration = hashtable.elements();
      
      while(enumeration.hasMoreElements()) {
         System.out.println(enumeration.nextElement());
      }
   }    
}

Output

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

3
2
1

Getting Enumeration of Values of a HashTable of Integer, String Pair Example

The following example shows the usage of Java Hashtable elements() method to iterate over the values of a Hashtable using Enumeration. We've created a Hashtable object of Integer,String pairs. Then few entries are added. An enumeration is retrieved using elements() method and then it is iterated to print the values of the hashtable.

package com.tutorialspoint;

import java.util.Enumeration;
import java.util.Hashtable;

public class HashtableDemo {
   public static void main(String args[]) {
      
      // create hash table
      Hashtable<Integer,String> hashtable = new Hashtable<>();

      // populate hash table
      hashtable.put(1, "tutorials");
      hashtable.put(2, "point");
      hashtable.put(3, "is best"); 

      Enumeration<String> enumeration = hashtable.elements();
      
      while(enumeration.hasMoreElements()) {
         System.out.println(enumeration.nextElement());
      }
   }    
}

Output

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

is best
point
tutorials

Getting Enumeration of Values of a HashTable of Integer, Object Pair Example

The following example shows the usage of Java Hashtable elements() method to iterate over the values of a Hashtable using Enumeration. We've created a Hashtable object of Integer,Student pairs. Then few entries are added. An enumeration is retrieved using elements() method and then it is iterated to print the values of the hashtable.

package com.tutorialspoint;

import java.util.Enumeration;
import java.util.Hashtable;

public class HashtableDemo {
   public static void main(String args[]) {
      
      // create hash table
      Hashtable<Integer,Student> hashtable = new Hashtable<>();

      // populate hash table
      hashtable.put(1, new Student(1, "Julie"));
      hashtable.put(2, new Student(2, "Robert"));
      hashtable.put(3, new Student(3, "Adam"));

      Enumeration<Student> enumeration = hashtable.elements();
      
      while(enumeration.hasMoreElements()) {
         System.out.println(enumeration.nextElement());
      } 
   }    
}
class Student {
   int rollNo;
   String name;

   Student(int rollNo, String name){
      this.rollNo = rollNo;
      this.name = name;
   }

   @Override
   public String toString() {
      return "[ " + this.rollNo + ", " + this.name + " ]";
   }
   @Override
   public boolean equals(Object obj) {
      if(obj == null) return false;
      Student s = (Student)obj;
      return this.rollNo == s.rollNo && this.name.equalsIgnoreCase(s.name);
   }
}

Output

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

[ 3, Adam ]
[ 2, Robert ]
[ 1, Julie ]