Class PublicKey

java.lang.Object
com.codename1.security.Key
com.codename1.security.PublicKey
public final class PublicKey extends Key

A public key -- paired with a PrivateKey to form a key pair. Carries the algorithm name ("RSA" or "EC") and the encoded key bytes.

PEM files (-----BEGIN PUBLIC KEY-----) go through fromPem(String), which strips the armor and decodes the base64 for you, and which also takes the -----BEGIN CERTIFICATE----- file a server or gateway is more likely to hand out; fromX509(String, byte[]) is the lower level entry point for callers that already hold the DER bytes.

  • Field Details

  • Method Details

    • fromX509

      public static PublicKey fromX509(String algorithm, byte[] x509Der)
      Wraps an X.509 / SubjectPublicKeyInfo (SPKI) DER blob. This is the format produced by openssl rsa -pubout or openssl ec -pubout.

    • rsa

      public static PublicKey rsa(byte[] x509Der)
      Convenience: build an RSA PublicKey from a fromX509(String, byte[]) X.509 blob.

    • fromPem

      public static PublicKey fromPem(String pem)

      Parses a PEM-encoded public key, determining the algorithm from the key itself. This is the form openssl rsa -pubout and every backend key store hands out:

      InputStream is = Display.getInstance().getResourceAsStream(MyApp.class, "/public.pem");
PublicKey key = PublicKey.fromPem(Util.readInputStream(is));

      Accepts a PUBLIC KEY (SPKI) block, the older PKCS#1 RSA PUBLIC KEY block, and -- for keys carried in JSON or a build hint rather than a file -- bare base64 with no -----BEGIN----- armor at all. Line endings, blank lines and text surrounding the block are ignored, and in a file holding several blocks the first public key is the one used.

      A CERTIFICATE block is accepted as well, and its subject public key is used. That covers the file a backend usually hands out -- a TLS or signing certificate rather than a bare key -- without the caller having to run openssl x509 -pubkey -noout first. In a certificate chain the leaf comes first, so the key that comes out is the chain's own. Note that nothing is being trusted by doing this: the signature and the validity dates are not checked, and the certificate is read only as a container for the key it names.

      Throws CryptoException if the text is not a public key, if it is passphrase-encrypted, or if the key is neither RSA nor EC.

    • fromPem

      public static PublicKey fromPem(byte[] pem)
      fromPem(String) over the raw bytes of a .pem file, so a stream read with Util.readInputStream can be passed straight in. The bytes are decoded as UTF-8.

    • fromPem

      public static PublicKey fromPem(String algorithm, String pem)
      fromPem(String) with the algorithm supplied by the caller rather than read from the key. Use this only for a key whose algorithm OID this class does not recognize but the platform does.

    • fromPem

      public static PublicKey fromPem(String algorithm, byte[] pem)
      fromPem(String,String) over the raw bytes of a .pem file.