Java Collections emptySortedSet() Method

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Description

The Java Collections emptySortedSet() method is used to get the empty sorted set (immutable). This set is serializable.

Declaration

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

 
public static final <T> SortedSet<T> emptySortedSet()

Parameters

NA

Return Value

NA

Exception

NA

Getting Empty SortedSet of Integers Example

The following example shows the usage of Java Collection emptySortedSet() method to get an empty sorted set of Integers. We've created an empty sorted set using emptySortedSet() method and then tried adding few elements to it which results in exception.

 
package com.tutorialspoint;

import java.util.Collections;
import java.util.SortedSet;

public class CollectionsDemo {
   public static void main(String args[]) {
      
      // create an empty sorted set    
      SortedSet<Integer> emptySortedSet = Collections.emptySortedSet();

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

      // try to add elements
      emptySortedSet.add(1);
      emptySortedSet.add(2);
   }    
}

Output

Let us compile and run the above program, this will produce the following result.Exception will be thrown as the list is immutable.

Created empty immutable sorted set: []
Exception in thread "main" java.lang.UnsupportedOperationException
	at java.base/java.util.Collections$UnmodifiableCollection.add(Collections.java:1060)
	at com.tutorialspoint.CollectionsDemo.main(CollectionsDemo.java:15)

Getting Empty SortedSet of Strings Example

The following example shows the usage of Java Collection emptySortedSet() method to get an empty sorted set of Strings. We've created an empty sorted set using emptySortedSet() method and then tried adding few elements to it which results in exception.

 
package com.tutorialspoint;

import java.util.Collections;
import java.util.SortedSet;

public class CollectionsDemo {
   public static void main(String args[]) {
      
      // create an empty sorted set    
      SortedSet<String> emptySortedSet = Collections.emptySortedSet();

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

      // try to add elements
      emptySortedSet.add("A");
      emptySortedSet.add("B");
   }    
}

Output

Let us compile and run the above program, this will produce the following result.Exception will be thrown as the list is immutable.

Created empty immutable sorted set: []
Exception in thread "main" java.lang.UnsupportedOperationException
	at java.base/java.util.Collections$UnmodifiableCollection.add(Collections.java:1060)
	at com.tutorialspoint.CollectionsDemo.main(CollectionsDemo.java:15)

Getting Empty SortedSet of Object Example

The following example shows the usage of Java Collection emptySortedSet() method to get an empty sorted set of Student objects. We've created an empty sorted set using emptySortedSet() method and then tried adding few elements to it which results in exception.

 
package com.tutorialspoint;

import java.util.Collections;
import java.util.SortedSet;

public class CollectionsDemo {
   public static void main(String args[]) {
      
      // create an empty sorted set    
      SortedSet<Student> emptySortedSet = Collections.emptySortedSet();

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

      // try to add elements
      emptySortedSet.add(new Student(1, "Julie"));
      emptySortedSet.add(new Student(2, "Robert"));
   }    
}
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 + " ]";
   }
}

Output

Let us compile and run the above program, this will produce the following result.Exception will be thrown as the list is immutable.

Created empty immutable sorted set: []
Exception in thread "main" java.lang.UnsupportedOperationException
	at java.base/java.util.Collections$UnmodifiableCollection.add(Collections.java:1060)
	at com.tutorialspoint.CollectionsDemo.main(CollectionsDemo.java:15)