KeyFactory getInstance() method in Java with Examples

getInstance(String algorithm)

The getInstance() method of java.security.KeyFactory class returns a object of KeyFactory type that applys the assigned KeyFactory algorithm.

Syntax:

public static KeyFactory
  getInstance(String algorithm)
  throws NoSuchAlgorithmException

Parameters: This method seeks the standard Algorithm as a parameter whose instance is to be created to this KeyFactory instance.



Return Value: This method returns a new key factory object.

Exception: This method throws following exception:

  • NoSuchAlgorithmException: if no provider is available to support an key factory spi application for the particular algorithm.
  • NullPointerException: if algorithm is null.

Below are the examples to illustrate the getInstance() method:

Example 1:

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java program to demonstrate
// getInstance() method
  
import java.security.*;
import java.util.*;
  
public class GFG1 {
    public static void main(String[] argv)
    {
  
        try {
  
            // creating the object of KeyFactory
            // and getting instance
            // By usng getInstance() method
            KeyFactory sr
                = KeyFactory.getInstance("DSA");
  
            // getting the algoritm of KeyFactory object
            String str = sr.getAlgorithm();
  
            // printing the status
            System.out.println("algorithm : " + str);
        }
  
        catch (NoSuchAlgorithmException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (NullPointerException e) {
  
            System.out.println("Exception thrown : " + e);
        }
    }
}

chevron_right


Output:

algorithm : DSA

Example 2: To show NoSuchAlgorithmException

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java program to demonstrate
// getInstance() method
  
import java.security.*;
import java.util.*;
  
public class GFG1 {
    public static void main(String[] argv)
    {
  
        try {
  
            // creating the object of KeyFactory
            // and getting instance
            // By usng getInstance() method
            KeyFactory sr = KeyFactory.getInstance("GEEKS");
  
            // getting the algoritm of KeyFactory object
            String str = sr.getAlgorithm();
  
            // printing the status
            System.out.println("algorithm : " + str);
        }
  
        catch (NoSuchAlgorithmException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (NullPointerException e) {
  
            System.out.println("Exception thrown : " + e);
        }
    }
}

chevron_right


Output:

Exception thrown :
 java.security.NoSuchAlgorithmException:
 GEEKS KeyFactory not available

getInstance(String algorithm, String provider)

The getInstance() method of java.security.KeyFactory class returns a object of KeyFactory type that applys the assigned KeyFactory algorithm and assigned provider object.

Syntax:

public static KeyFactory
  getInstance(String algorithm, String provider)
  throws NoSuchAlgorithmException

Parameters: This method seeks the following arguments as a parameters:


  • algorithm: which is the name of the algorithm specified to get the instance.
  • provider: which is the name of the provider to be specified

Return Value: This method returns an new key factory object.

Exception: This method throws following exceptions:

  • NoSuchAlgorithmException:– if no provider is available to support an key factory spi application for the particular algorithm.
  • IllegalArgumentException:– if the provider is null.
  • NullPointerException:– if algorithm is null

Below are the examples to illustrate the getInstance() method:

Example 1:

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java program to demonstrate
// getInstance() method
  
import java.security.*;
import java.util.*;
  
public class GFG1 {
    public static void main(String[] argv)
    {
        try {
            // creating the object of KeyFactory
            // and getting instance
            // By usng getInstance() method
            KeyFactory sr
                = KeyFactory.getInstance(
                    "DSA", "SUN");
  
            // getting the algoritm of KeyFactory object
            String str = sr.getAlgorithm();
  
            // printing the status
            System.out.println("algorithm : " + str);
        }
  
        catch (NoSuchAlgorithmException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (NullPointerException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (NoSuchProviderException e) {
  
            System.out.println("Exception thrown : " + e);
        }
    }
}

chevron_right


Output:

algorithm : DSA

Example 2: To show NoSuchAlgorithmException

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java program to demonstrate
// getInstance() method
  
import java.security.*;
import java.util.*;
  
public class GFG1 {
    public static void main(String[] argv)
    {
        try {
            // creating the object of KeyFactory
            // and getting instance
            // By usng getInstance() method
            KeyFactory sr
                = KeyFactory.getInstance(
                    "RSA", "SUN");
  
            // getting the algoritm of KeyFactory object
            String str = sr.getAlgorithm();
  
            // printing the status
            System.out.println("algorithm : " + str);
        }
  
        catch (NoSuchAlgorithmException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (NullPointerException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (NoSuchProviderException e) {
  
            System.out.println("Exception thrown : " + e);
        }
    }
}

chevron_right


Output:

Exception thrown :
 java.security.NoSuchAlgorithmException:
 no such algorithm: RSA for provider SUN

Reference: https://docs.oracle.com/javase/9/docs/api/java/security/KeyFactory.html#getInstance-java.lang.String-



My Personal Notes arrow_drop_up

Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.