/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package java.security;
import java.io.IOException;
import java.security.spec.AlgorithmParameterSpec;
import java.security.spec.InvalidParameterSpecException;
import org.apache.harmony.security.fortress.Engine;
/**
* {@code AlgorithmParameters} is an engine class which provides algorithm
* parameters.
*/
public class AlgorithmParameters {
/**
* The service name.
*/
private static final String SEVICE = "AlgorithmParameters";
/**
* Used to access common engine functionality.
*/
private static final Engine ENGINE = new Engine(SEVICE);
/**
* The security provider.
*/
private final Provider provider;
/**
* The SPI implementation.
*/
private final AlgorithmParametersSpi spiImpl;
/**
* The security algorithm.
*/
private final String algorithm;
/**
* The initialization state.
*/
private boolean initialized;
/**
* Constructs a new instance of {@code AlgorithmParameters} with the given
* arguments.
*
* @param algPramSpi
* the concrete implementation.
* @param provider
* the security provider.
* @param algorithm
* the name of the algorithm.
*/
protected AlgorithmParameters(AlgorithmParametersSpi algPramSpi,
Provider provider, String algorithm) {
this.provider = provider;
this.algorithm = algorithm;
this.spiImpl = algPramSpi;
}
/**
* Returns a new instance of {@code AlgorithmParameters} for the specified
* algorithm.
*
* @param algorithm
* the name of the algorithm to use.
* @return a new instance of {@code AlgorithmParameters} for the specified
* algorithm.
* @throws NoSuchAlgorithmException
* if the specified algorithm is not available.
* @throws NullPointerException
* if {@code algorithm} is {@code null}.
*/
public static AlgorithmParameters getInstance(String algorithm)
throws NoSuchAlgorithmException {
if (algorithm == null) {
throw new NullPointerException();
}
Engine.SpiAndProvider sap = ENGINE.getInstance(algorithm, null);
return new AlgorithmParameters((AlgorithmParametersSpi) sap.spi, sap.provider, algorithm);
}
/**
* Returns a new instance of {@code AlgorithmParameters} from the specified
* provider for the specified algorithm.
*
* @param algorithm
* the name of the algorithm to use.
* @param provider
* name of the provider of the {@code AlgorithmParameters}.
* @return a new instance of {@code AlgorithmParameters} for the specified
* algorithm.
* @throws NoSuchAlgorithmException
* if the specified algorithm is not available.
* @throws NoSuchProviderException
* if the specified provider is not available.
* @throws IllegalArgumentException if {@code provider == null || provider.isEmpty()}
* @throws NullPointerException
* if {@code algorithm} is {@code null}.
*/
public static AlgorithmParameters getInstance(String algorithm,
String provider) throws NoSuchAlgorithmException,
NoSuchProviderException {
if (provider == null || provider.isEmpty()) {
throw new IllegalArgumentException();
}
Provider p = Security.getProvider(provider);
if (p == null) {
throw new NoSuchProviderException(provider);
}
return getInstance(algorithm, p);
}
/**
* Returns a new instance of {@code AlgorithmParameters} from the specified
* provider for the specified algorithm.
*
* @param algorithm
* the name of the algorithm to use.
* @param provider
* the provider of the {@code AlgorithmParameters}.
* @return a new instance of {@code AlgorithmParameters} for the specified
* algorithm.
* @throws NoSuchAlgorithmException
* if the specified algorithm is not available.
* @throws NullPointerException
* if {@code algorithm} is {@code null}.
* @throws IllegalArgumentException if {@code provider == null}
*/
public static AlgorithmParameters getInstance(String algorithm,
Provider provider) throws NoSuchAlgorithmException {
if (provider == null) {
throw new IllegalArgumentException();
}
if (algorithm == null) {
throw new NullPointerException();
}
Object spi = ENGINE.getInstance(algorithm, provider, null);
return new AlgorithmParameters((AlgorithmParametersSpi) spi, provider, algorithm);
}
/**
* Returns the provider associated with this {@code AlgorithmParameters}.
*
* @return the provider associated with this {@code AlgorithmParameters}.
*/
public final Provider getProvider() {
return provider;
}
/**
* Returns the name of the algorithm.
*
* @return the name of the algorithm.
*/
public final String getAlgorithm() {
return algorithm;
}
/**
* Initializes this {@code AlgorithmParameters} with the specified {@code
* AlgorithmParameterSpec}.
*
* @param paramSpec
* the parameter specification.
* @throws InvalidParameterSpecException
* if this {@code AlgorithmParameters} has already been
* initialized or the given {@code paramSpec} is not appropriate
* for initializing this {@code AlgorithmParameters}.
*/
public final void init(AlgorithmParameterSpec paramSpec)
throws InvalidParameterSpecException {
if (initialized) {
throw new InvalidParameterSpecException("Parameter has already been initialized");
}
spiImpl.engineInit(paramSpec);
initialized = true;
}
/**
* Initializes this {@code AlgorithmParameters} with the specified {@code
* byte[]} using the default decoding format for parameters. The default
* encoding format is ASN.1.
*
* @param params
* the encoded parameters.
* @throws IOException
* if this {@code AlgorithmParameters} has already been
* initialized, or the parameter could not be encoded.
*/
public final void init(byte[] params) throws IOException {
if (initialized) {
throw new IOException("Parameter has already been initialized");
}
spiImpl.engineInit(params);
initialized = true;
}
/**
* Initializes this {@code AlgorithmParameters} with the specified {@code
* byte[]} using the specified decoding format.
*
* @param params
* the encoded parameters.
* @param format
* the name of the decoding format.
* @throws IOException
* if this {@code AlgorithmParameters} has already been
* initialized, or the parameter could not be encoded.
*/
public final void init(byte[] params, String format) throws IOException {
if (initialized) {
throw new IOException("Parameter has already been initialized");
}
spiImpl.engineInit(params, format);
initialized = true;
}
/**
* Returns the {@code AlgorithmParameterSpec} for this {@code
* AlgorithmParameters}.
*
* @param paramSpec
* the type of the parameter specification in which this
* parameters should be converted.
* @return the {@code AlgorithmParameterSpec} for this {@code
* AlgorithmParameters}.
* @throws InvalidParameterSpecException
* if this {@code AlgorithmParameters} has already been
* initialized, or if this parameters could not be converted to
* the specified class.
*/
public final <T extends AlgorithmParameterSpec> T getParameterSpec(Class<T> paramSpec)
throws InvalidParameterSpecException {
if (!initialized) {
throw new InvalidParameterSpecException("Parameter has not been initialized");
}
return spiImpl.engineGetParameterSpec(paramSpec);
}
/**
* Returns this {@code AlgorithmParameters} in their default encoding
* format. The default encoding format is ASN.1.
*
* @return the encoded parameters.
* @throws IOException
* if this {@code AlgorithmParameters} has already been
* initialized, or if this parameters could not be encoded.
*/
public final byte[] getEncoded() throws IOException {
if (!initialized) {
throw new IOException("Parameter has not been initialized");
}
return spiImpl.engineGetEncoded();
}
/**
* Returns this {@code AlgorithmParameters} in the specified encoding
* format.
*
* @param format
* the name of the encoding format.
* @return the encoded parameters.
* @throws IOException
* if this {@code AlgorithmParameters} has already been
* initialized, or if this parameters could not be encoded.
*/
public final byte[] getEncoded(String format) throws IOException {
if (!initialized) {
throw new IOException("Parameter has not been initialized");
}
return spiImpl.engineGetEncoded(format);
}
/**
* Returns a string containing a concise, human-readable description of this
* {@code AlgorithmParameters}.
*
* @return a printable representation for this {@code AlgorithmParameters}.
*/
@Override
public final String toString() {
if (!initialized) {
return null;
}
return spiImpl.engineToString();
}
}