e199. getting the bytes of a generated key pair.txt

这里面包含了一百多个JAVA源文件

try {
        String algorithm = "DSA";  // or RSA, DH, etc.
    
        // Generate a 1024-bit Digital Signature Algorithm (DSA) key pair
        KeyPairGenerator keyGen = KeyPairGenerator.getInstance(algorithm);
        keyGen.initialize(1024);
        KeyPair keypair = keyGen.genKeyPair();
        PrivateKey privateKey = keypair.getPrivate();
        PublicKey publicKey = keypair.getPublic();
    
        // Get the bytes of the public and private keys
        byte[] privateKeyBytes = privateKey.getEncoded();
        byte[] publicKeyBytes = publicKey.getEncoded();
    
        // Get the formats of the encoded bytes
        String format = privateKey.getFormat();         // PKCS#8
        format = publicKey.getFormat();                 // X.509
    
    
        // The bytes can be converted back to public and private key objects
        KeyFactory keyFactory = KeyFactory.getInstance(algorithm);
        EncodedKeySpec privateKeySpec = new PKCS8EncodedKeySpec(privateKeyBytes);
        PrivateKey privateKey2 = keyFactory.generatePrivate(privateKeySpec);
    
        EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(publicKeyBytes);
        PublicKey publicKey2 = keyFactory.generatePublic(publicKeySpec);
    
        // The orginal and new keys are the same
        boolean same = privateKey.equals(privateKey2);  // true
        same = publicKey.equals(publicKey2);            // true
    } catch (InvalidKeySpecException e) {
    } catch (NoSuchAlgorithmException e) {
    }