KeyPairGenerator genKeyPair() method in Java

A key pair can be generated using the genKeyPair() method in the class java.security.KeyPairGenerator. This method requires no parameters and it returns the key pair that is generated.

A program that demonstrates this is given as follows −

Example

 Live Demo

import java.security.*;
import java.util.*;
public class Demo {
   public static void main(String[] argv) throws Exception {
      try {
         KeyPairGenerator kpGenerator = KeyPairGenerator.getInstance("RSA");
         KeyPair keyPair = kpGenerator.genKeyPair();
         System.out.println(keyPair);
      } catch (NoSuchAlgorithmException e) {
         System.out.println("Error!!! NoSuchAlgorithmException");
      }
   }
}

Output

java.security.KeyPair@12a3a380

Now let us understand the above program.

A key pair is generated using the genKeyPair() method and then this key pair is displayed. If the algorithm is wrong, then the exception NoSuchAlgorithmException is thrown. A code snippet that demonstrates is given as follows −

try {
   KeyPairGenerator kpGenerator = KeyPairGenerator.getInstance("RSA");
   KeyPair keyPair = kpGenerator.genKeyPair();
   System.out.println(keyPair);
} catch (NoSuchAlgorithmException e) {
   System.out.println("Error!!! NoSuchAlgorithmException");
}