Question

I need to convert certificate from DER format to pkcs#12 format. I know I can do this using openssl command. I am looking for java API / Class which can do this job.
Any help will be appreciated.

Answer 1

You can try to load the PKCS#12 container as a keystore:

java.security.KeyStore ks = java.security.KeyStore.getInstance("PKCS12");
ks.load(new java.io.FileInputStream("yourStore.p12"), "yourPassword".toCharArray());

Once loaded, you can enumerate the elements inside the container:

for(Enumeration enum = ks.aliases(); enum.hasMoreElements(); ) {
    String alias = (String) enum.nextElement();
    System.out.println("@:" + alias);
    if (ks.isKeyEntry(alias)) {
        System.out.println("return PrivateKey");
        PrivateKey pk = (PrivateKey) ks.getKey(alias, password);
        // ...
    }
}