Remove all Hashtable elements in Java

Deleting all values from a Hashtable is done in two different ways:
  1. By browsing the table and deleting the current element.
  2. By directly calling the method clear().

1) Browse and delete the key-value pairs of Hashtable

This method is useful when you don't want to remove all values by adding a statement that tests whether the item that is going to be deleted is affected. In this example we don't make exceptions, so we delete everything.

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

public class removeAll_Hashtable {
 public static void main(String[] s) {
 Hashtable table = new Hashtable(); 
 table.put("1", "val1"); 
 table.put("2", "val2"); 
 table.put("3", "val3"); 
 
 Enumeration e = table.keys(); 
 while (e.hasMoreElements()) {
 String key = (String) e.nextElement(); 
 System.out.println(key + " : " + table.get(key)); 
 table.remove(key); 
 }
 System.out.println("After deletion"); 
 System.out.println(table); 
 }
}
Output: 

3: val3
2: val2
1: val1
After deletion
{}

2) Delete key-value peers in calling the clear()

This method is finer because it saves us from writing code.

public void clear(): Empty the entire table so that it does not contain any items.

import java.util.Hashtable; 

public class removeAll_Hashtable {
 public static void main(String[] s) {
 Hashtable table = new Hashtable(); 
 table.put("1", "val1"); 
 table.put("2", "val2"); 
 table.put("3", "val3"); 
 
 table.clear(); 
 System.out.println("After calling clear()"); 
 System.out.println(table); 
 }
}
Output: 

After calling clear()
{}
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