Skip to content
Related Articles

Related Articles

Improve Article
KeyStore getCertificate() method in Java with Examples
  • Last Updated : 14 Oct, 2019

The getCertificate() method of java.security.KeyStore class is used to provide the certificate for the requested alias. .

Syntax:

public final Certificate
  getCertificate(String alias)
  throws KeyStoreException

Parameter: This method accepts the name of the alias as a parameter whose certificate is to be fetched.

Return Value: This method returns the certificate for the requested alias if it exists.

Exception: This method throws KeyStoreException if you don’t initialize this keystore.



Note: All the programs in this article won’t run on online IDE as no ‘privatekey’ Keystore exists. You can check this code on Java compiler on your system. To check this code, create a Keystore ‘privatekey’ on your system and set your own keystore password to access that keystore.

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

Example 1:




// Java program to demonstrate
// getCertificate() method
  
import java.security.*;
import java.security.cert.*;
import java.util.*;
import java.io.*;
  
public class GFG {
    public static void main(String[] argv)
    {
        try {
  
            // creating the object of KeyStore
            // and getting instance
            // By usng getInstance() method
            KeyStore sr = KeyStore.getInstance("JKS");
  
            // keystore password is required to access keystore
            char[] pass = ("123456").toCharArray();
  
            // creating and intializing object of InputStream
            InputStream is
                = new FileInputStream(
                    "f:/java/private key.store");
  
            // intializing keystore object
            sr.load(is, pass);
  
            // getting the certificate
            // using getCertificate() method
            X509Certificate cert
                = (X509Certificate)sr
                      .getCertificate("ftpkey");
  
            // display the result
            System.out.println("Certificate version : "
                               + cert.getVersion());
        }
  
        catch (NoSuchAlgorithmException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (NullPointerException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (KeyStoreException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (FileNotFoundException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (IOException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (CertificateException e) {
  
            System.out.println("Exception thrown : " + e);
        }
    }
}
Output:
Certificate version : 3

Example 2: For KeyStoreException




// Java program to demonstrate
// getCertificate() method
  
import java.security.*;
import java.security.cert.*;
import java.util.*;
import java.io.*;
  
public class GFG {
    public static void main(String[] argv)
    {
        try {
  
            // creating the object of KeyStore
            // and getting instance
            // By usng getInstance() method
            KeyStore sr = KeyStore.getInstance("JKS");
  
            // intializing keystore object
            // sr.load(is, pass);
  
            // getting the certificate
            // using getCertificate() method
            X509Certificate cert
                = (X509Certificate)sr
                      .getCertificate("ftpkey");
  
            // display the result
            System.out.println("Certificate version : "
                               + cert.getVersion());
        }
        catch (NullPointerException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (KeyStoreException e) {
  
            System.out.println("Exception thrown : " + e);
        }
    }
}
Output:
Exception thrown :
 java.security.KeyStoreException:
 Uninitialized keystore

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

Attention reader! Don’t stop learning now. Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready. To complete your preparation from learning a language to DS Algo and many more,  please refer Complete Interview Preparation Course.




My Personal Notes arrow_drop_up
Recommended Articles
Page :