/**
* Returns a KeyPairGenerator object that generates public/private key pairs for the specified
* algorithm.
*
* <p>This method traverses the list of registered security Providers, starting with the most
* preferred Provider. A new KeyPairGenerator object encapsulating the KeyPairGeneratorSpi
* implementation from the first Provider that supports the specified algorithm is returned.
*
* <p>Note that the list of registered providers may be retrieved via the {@link
* Security#getProviders() Security.getProviders()} method.
*
* @param algorithm the standard string name of the algorithm. See Appendix A in the <a href=
* "../../../technotes/guides/security/crypto/CryptoSpec.html#AppA"> Java Cryptography
* Architecture API Specification & Reference </a> for information about standard
* algorithm names.
* @return the new KeyPairGenerator object.
* @exception NoSuchAlgorithmException if no Provider supports a KeyPairGeneratorSpi
* implementation for the specified algorithm.
* @see Provider
*/
public static KeyPairGenerator getInstance(String algorithm) throws NoSuchAlgorithmException {
List<Service> list = GetInstance.getServices("KeyPairGenerator", algorithm);
Iterator<Service> t = list.iterator();
if (t.hasNext() == false) {
throw new NoSuchAlgorithmException(algorithm + " KeyPairGenerator not available");
}
// find a working Spi or KeyPairGenerator subclass
NoSuchAlgorithmException failure = null;
do {
Service s = t.next();
try {
Instance instance = GetInstance.getInstance(s, KeyPairGeneratorSpi.class);
if (instance.impl instanceof KeyPairGenerator) {
return getInstance(instance, algorithm);
} else {
return new Delegate(instance, t, algorithm);
}
} catch (NoSuchAlgorithmException e) {
if (failure == null) {
failure = e;
}
}
} while (t.hasNext());
throw failure;
}
/*
* Returns an array of objects: the first object in the array is
* an instance of an implementation of the requested algorithm
* and type, and the second object in the array identifies the provider
* of that implementation.
* The <code>provider</code> argument can be null, in which case all
* configured providers will be searched in order of preference.
*/
static Object[] getImpl(String algorithm, String type, String provider)
throws NoSuchAlgorithmException, NoSuchProviderException {
if (provider == null) {
return GetInstance.getInstance(type, getSpiClass(type), algorithm).toArray();
} else {
return GetInstance.getInstance(type, getSpiClass(type), algorithm, provider).toArray();
}
}
static Instance getInstance(String type, Class<?> clazz, String algorithm, Provider provider)
throws NoSuchAlgorithmException {
Service s = GetInstance.getService(type, algorithm, provider);
Exception ve = JceSecurity.getVerificationResult(provider);
if (ve != null) {
String msg = "JCE cannot authenticate the provider " + provider.getName();
throw new SecurityException(msg, ve);
}
return GetInstance.getInstance(s, clazz);
}
static Instance getInstance(String type, Class<?> clazz, String algorithm, String provider)
throws NoSuchAlgorithmException, NoSuchProviderException {
Service s = GetInstance.getService(type, algorithm, provider);
Exception ve = getVerificationResult(s.getProvider());
if (ve != null) {
String msg = "JCE cannot authenticate the provider " + provider;
throw (NoSuchProviderException) new NoSuchProviderException(msg).initCause(ve);
}
return GetInstance.getInstance(s, clazz);
}
/**
* Returns a {@code CertPathValidator} object that implements the specified algorithm.
*
* <p>A new CertPathValidator object encapsulating the CertPathValidatorSpi implementation from
* the specified Provider object is returned. Note that the specified Provider object does not
* have to be registered in the provider list.
*
* @param algorithm the name of the requested {@code CertPathValidator} algorithm. See the
* CertPathValidator section in the <a href=
* "{@docRoot}/../technotes/guides/security/StandardNames.html#CertPathValidator"> Java
* Cryptography Architecture Standard Algorithm Name Documentation</a> for information about
* standard algorithm names.
* @param provider the provider.
* @return a {@code CertPathValidator} object that implements the specified algorithm.
* @exception NoSuchAlgorithmException if a CertPathValidatorSpi implementation for the specified
* algorithm is not available from the specified Provider object.
* @exception IllegalArgumentException if the {@code provider} is null.
* @see java.security.Provider
*/
public static CertPathValidator getInstance(String algorithm, Provider provider)
throws NoSuchAlgorithmException {
Instance instance =
GetInstance.getInstance(
"CertPathValidator", CertPathValidatorSpi.class, algorithm, provider);
return new CertPathValidator(
(CertPathValidatorSpi) instance.impl, instance.provider, algorithm);
}
/**
* Returns a <code>KeyManagerFactory</code> object that acts as a factory for key managers.
*
* <p>This method traverses the list of registered security Providers, starting with the most
* preferred Provider. A new KeyManagerFactory object encapsulating the KeyManagerFactorySpi
* implementation from the first Provider that supports the specified algorithm is returned.
*
* <p>Note that the list of registered providers may be retrieved via the {@link
* Security#getProviders() Security.getProviders()} method.
*
* @implNote The JDK Reference Implementation additionally uses the {@code
* jdk.security.provider.preferred} {@link Security#getProperty(String) Security} property to
* determine the preferred provider order for the specified algorithm. This may be different
* than the order of providers returned by {@link Security#getProviders()
* Security.getProviders()}.
* @param algorithm the standard name of the requested algorithm. See the <a href=
* "{@docRoot}/../technotes/guides/security/jsse/JSSERefGuide.html"> Java Secure Socket
* Extension Reference Guide </a> for information about standard algorithm names.
* @return the new {@code KeyManagerFactory} object
* @throws NoSuchAlgorithmException if no {@code Provider} supports a {@code KeyManagerFactorySpi}
* implementation for the specified algorithm
* @throws NullPointerException if {@code algorithm} is {@code null}
* @see java.security.Provider
*/
public static final KeyManagerFactory getInstance(String algorithm)
throws NoSuchAlgorithmException {
Objects.requireNonNull(algorithm, "null algorithm name");
GetInstance.Instance instance =
GetInstance.getInstance("KeyManagerFactory", KeyManagerFactorySpi.class, algorithm);
return new KeyManagerFactory(
(KeyManagerFactorySpi) instance.impl, instance.provider, algorithm);
}
static Instance getInstance(String type, Class<?> clazz, String algorithm)
throws NoSuchAlgorithmException {
List<Service> services = GetInstance.getServices(type, algorithm);
NoSuchAlgorithmException failure = null;
for (Service s : services) {
if (canUseProvider(s.getProvider()) == false) {
// allow only signed providers
continue;
}
try {
Instance instance = GetInstance.getInstance(s, clazz);
return instance;
} catch (NoSuchAlgorithmException e) {
failure = e;
}
}
throw new NoSuchAlgorithmException("Algorithm " + algorithm + " not available", failure);
}
static Object[] getImpl(String algorithm, String type, Provider provider, Object params)
throws NoSuchAlgorithmException, InvalidAlgorithmParameterException {
return GetInstance.getInstance(type, getSpiClass(type), algorithm, params, provider).toArray();
}
/*
* Returns an array of objects: the first object in the array is
* an instance of an implementation of the requested algorithm
* and type, and the second object in the array identifies the provider
* of that implementation.
* The <code>provider</code> argument cannot be null.
*/
static Object[] getImpl(String algorithm, String type, Provider provider)
throws NoSuchAlgorithmException {
return GetInstance.getInstance(type, getSpiClass(type), algorithm, provider).toArray();
}
/**
* Returns a KeyPairGenerator object that generates public/private key pairs for the specified
* algorithm.
*
* <p>A new KeyPairGenerator object encapsulating the KeyPairGeneratorSpi implementation from the
* specified Provider object is returned. Note that the specified Provider object does not have to
* be registered in the provider list.
*
* @param algorithm the standard string name of the algorithm. See Appendix A in the <a href=
* "../../../technotes/guides/security/crypto/CryptoSpec.html#AppA"> Java Cryptography
* Architecture API Specification & Reference </a> for information about standard
* algorithm names.
* @param provider the provider.
* @return the new KeyPairGenerator object.
* @exception NoSuchAlgorithmException if a KeyPairGeneratorSpi implementation for the specified
* algorithm is not available from the specified Provider object.
* @exception IllegalArgumentException if the specified provider is null.
* @see Provider
* @since 1.4
*/
public static KeyPairGenerator getInstance(String algorithm, Provider provider)
throws NoSuchAlgorithmException {
Instance instance =
GetInstance.getInstance("KeyPairGenerator", KeyPairGeneratorSpi.class, algorithm, provider);
return getInstance(instance, algorithm);
}