我正在使用 BouncyCastle 1.57 （bcprov-jdk15on，bcmail-jdk15on和bcpkix-jdk15on）和
Java 7 。
您可以使用
JcaPEMKeyConverter该类读取私钥。以下代码适用于带有和不带有密码的密钥：
import org.bouncycastle.jce.provider.BouncyCastleProvider;import org.bouncycastle.openssl.PEMDecryptorProvider;import org.bouncycastle.openssl.PEMEncryptedKeyPair;import org.bouncycastle.openssl.PEMKeyPair;import org.bouncycastle.openssl.PEMParser;import org.bouncycastle.openssl.jcajce.JcaPEMKeyConverter;import org.bouncycastle.openssl.jcajce.JcePEMDecryptorProviderBuilder;// don't forget to add the providerSecurity.addProvider(new BouncyCastleProvider());String password = "your password";// reads your key filePEMParser pemParser = new PEMParser(new FileReader(keyFile));Object object = pemParser.readObject();JcaPEMKeyConverter converter = new JcaPEMKeyConverter().setProvider("BC");KeyPair kp;if (object instanceof PEMEncryptedKeyPair) { // Encrypted key - we will use provided password PEMEncryptedKeyPair ckp = (PEMEncryptedKeyPair) object; // uses the password to decrypt the key PEMDecryptorProvider decProv = new JcePEMDecryptorProviderBuilder().build(password.toCharArray()); kp = converter.getKeyPair(ckp.decryptKeyPair(decProv));} else { // Unencrypted key - no password needed PEMKeyPair ukp = (PEMKeyPair) object; kp = converter.getKeyPair(ukp);}// RSAKeyFactory keyFac = KeyFactory.getInstance("RSA");RSAPrivateCrtKeySpec privateKey = keyFac.getKeySpec(kp.getPrivate(), RSAPrivateCrtKeySpec.class);System.out.println(privateKey.getClass());所述
privateKey的类将是
java.security.spec.RSAPrivateCrtKeySpec（延伸
RSAPrivateKeySpec）。
