String encodedURL = Base64.getUrlEncoder()
                       .encodeToString(actualURL_String.getBytes());

byte[] decodedURLBytes = Base64.getUrlDecoder().decode(encodedURLString);

String actualURL= new String(decodedURLBytes);

// Java program to demonstrate
// URL encoding using Base64 class
  
import java.util.*;
public class GFG {
    public static void main(String[] args)
    {
        // create a sample url String to encode
        String sampleURL = "https:// www.geeksforgeeks.org/";
  
        // print actual URL String
        System.out.println("Sample URL:\n"
                           + sampleURL);
  
        // Encode into Base64 URL format
        String encodedURL = Base64.getUrlEncoder()
                                .encodeToString(sampleURL.getBytes());
  
        // print encoded URL
        System.out.println("encoded URL:\n"
                           + encodedURL);
    }
}

Sample URL:
https://www.geeksforgeeks.org/
encoded URL:
aHR0cHM6Ly93d3cuZ2Vla3Nmb3JnZWVrcy5vcmcv

// Java program to demonstrate
// Decoding Basic Base 64 format to String
  
import java.util.*;
public class GFG {
    public static void main(String[] args)
    {
        // create a encoded URL to decode
        String encoded = "aHR0cHM6Ly93d3cuZ2Vla3Nmb3JnZWVrcy5vcmcv";
  
        // print encoded URL
        System.out.println("encoded URL:\n"
                           + encoded);
  
        // decode into String URL from encoded format
        byte[] actualByte = Base64.getUrlDecoder()
                                .decode(encoded);
  
        String actualURLString = new String(actualByte);
  
        // print actual String
        System.out.println("actual String:\n"
                           + actualURLString);
    }
}

encoded URL:
aHR0cHM6Ly93d3cuZ2Vla3Nmb3JnZWVrcy5vcmcv
actual String:
https://www.geeksforgeeks.org/