java.util.Collections.emptySet() Method


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Description

The emptySet() method is used to get the empty set (immutable). This set is serializable.

Declaration

Following is the declaration for java.util.Collections.emptySet() method.

public static final <T> Set<T> emptySet()

Parameters

NA

Return Value

NA

Exception

NA

Example

The following example shows the usage of java.util.Collections.emptySet()

Live Demo
package com.tutorialspoint;

import java.util.*;

public class CollectionsDemo {
   public static void main(String args[]) {

      // create an empty set    
      Set emptyset = Collections.emptySet();

      System.out.println("Created empty immutable set: "+emptyset);  

      // try to add elements
      emptyset.add("Adding");
   }    
}

Let us compile and run the above program, this will produce the following result.The set is immutable so adding elements will throw exception.

Created empty immutable set: []
Exception in thread "main" java.lang.UnsupportedOperationException

java_util_collections.htm

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