Java Collections emptyMap() Method with Examples

The emptyMap() method of Java Collections is a method that is used to return an empty map such that we can not change the data in map IE it is immutable.

Syntax:

public static final <Key,Value> Map<Key,Value> emptyMap()   

where, 

• key is the key element
• value is the value element

Parameters: This will not accept any parameters,

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

Exceptions: It will not arise any exception.

Example 1:

Java

// Java program to create an empty map
import java.util.*;

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

        System.out.println(data);
    }
}

Output

{}

Example 2:

Java

// Java program to create an
// empty map and add elements
// We will get an error because
// the method will work on only
// an empty map
import java.util.*;

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

        // add element
        data.put("1", "python/R");

        System.out.println(data);
    }
}

Output:

Exception in thread "main" java.lang.UnsupportedOperationException
    at java.util.AbstractMap.put(AbstractMap.java:209)
    at GFG.main(GFG.java:8)