Java Collections emptySortedMap() Method with Examples

Last Updated : 03 Jan, 2022

The emptySortedMap() method of Java Collections is used to get a map that has no elements. A Sorted map is a data structure that can hold elements with key-value pairs in sorted order.

Syntax:

public static final <Key,Value> SortedMap<Key,Value> emptySortedMap()

where,

key is the key element
value is the value element

Parameters: This method does not take any parameters.

Return Type: It will return an empty sorted map that is immutable.

Example 1:

Java program to create an empty sorted map.

Java

import java.util.*;

public class GFG {
    // main method
    public static void main(String[] args)
    {
        // create an empty sorted map
        SortedMap<String, String> data
            = Collections.emptySortedMap();

        // display
        System.out.println(data);
    }
}

Output

{}

Example 2:

In this program, we are going to create an empty sorted map and add elements to the map. This method will return an error.

Java

import java.util.*;

public class GFG {
    // main method
    public static void main(String[] args)
    {
        // create an empty sorted map
        SortedMap<String, String> data
            = Collections.emptySortedMap();
      
        // add 3 elements
        data.put("1", "ojaswi");
        data.put("2", "ramya");
        data.put("3", "deepu");

        // display
        System.out.println(data);
    }
}

Output:

Exception in thread "main" java.lang.UnsupportedOperationException
    at java.util.Collections$UnmodifiableMap.put(Collections.java:1459)
    at GFG.main(GFG.java:10)

Example 3:

Java

import java.util.*;

public class GFG {
    // main method
    public static void main(String[] args)
    {
        // create an empty sorted map
        SortedMap<Integer, Integer> data
            = Collections.emptySortedMap();
      
        // add 3 elements
        data.put(1, 34);
        data.put(2, 45);
        data.put(3, 56);

        // display
        System.out.println(data);
    }
}

Output:

Exception in thread "main" java.lang.UnsupportedOperationException
    at java.util.Collections$UnmodifiableMap.put(Collections.java:1459)
    at GFG.main(GFG.java:10)