content: /*
   *  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.
   */
  
  /**
  * @author Alexander Y. Kleymenov
  * @version $Revision$
  */
  
  package android.framework.org.apache.harmony.security_custom.x509;
  
  import java.util.Arrays;
  import android.framework.org.apache.harmony.security_custom.asn1.ASN1Any;
  import android.framework.org.apache.harmony.security_custom.asn1.ASN1Oid;
  import android.framework.org.apache.harmony.security_custom.asn1.ASN1Sequence;
  import android.framework.org.apache.harmony.security_custom.asn1.ASN1Type;
  import android.framework.org.apache.harmony.security_custom.asn1.BerInputStream;
  import android.framework.org.apache.harmony.security_custom.asn1.ObjectIdentifier;
  import android.framework.org.apache.harmony.security_custom.utils.AlgNameMapper;
  
  
  /**
   * The class encapsulates the ASN.1 DER encoding/decoding work
   * with the Algorithm Identifier which is a part of X.509 certificate
   * (as specified in RFC 3280 -
   *  Internet X.509 Public Key Infrastructure.
   *  Certificate and Certificate Revocation List (CRL) Profile.
   *  http://www.ietf.org/rfc/rfc3280.txt):
   *
   * <pre>
   *  AlgorithmIdentifier ::= SEQUENCE {
   *      algorithm OBJECT IDENTIFIER,
   *      parameters ANY DEFINED BY algorithm OPTIONAL
   *  }
   * </pre>
   */
  public final class AlgorithmIdentifier {
      /** the value of algorithm field */
      private String algorithm;
      /** the name of the algorithm */
      private String algorithmName;
      /** the value of parameters field */
      private byte[] parameters;
      /** the encoding of AlgorithmIdentifier value */
      private byte[] encoding;
  
      public AlgorithmIdentifier(String algorithm) {
          this(algorithm, null, null);
      }
  
      public AlgorithmIdentifier(String algorithm, byte[] parameters) {
          this(algorithm, parameters, null);
      }
  
      private AlgorithmIdentifier(String algorithm, byte[] parameters, byte[] encoding) {
          this.algorithm = algorithm;
          this.parameters = parameters;
          this.encoding = encoding;
      }
  
      /**
       * Returns the value of algorithm field of the structure.
       */
      public String getAlgorithm() {
          return algorithm;
      }
  
      /**
       * Returns the name of the algorithm corresponding to
       * its OID. If there is no the such correspondence,
       * algorithm OID is returned.
       */
      public String getAlgorithmName() {
          if (algorithmName == null) {
              algorithmName = AlgNameMapper.map2AlgName(algorithm);
              if (algorithmName == null) {
                  algorithmName = algorithm;
              }
          }
          return algorithmName;
      }
  
      /**
       * Returns the value of parameters field of the structure.
       */
      public byte[] getParameters() {
          return parameters;
      }
  
      /**
       * Returns ASN.1 encoded form of this X.509 AlgorithmIdentifier value.
       */
      public byte[] getEncoded() {
          if (encoding == null) {
              encoding = ASN1.encode(this);
          }
          return encoding;
      }
  
      @Override public boolean equals(Object ai) {
          if (!(ai instanceof AlgorithmIdentifier)) {
              return false;
          }
          AlgorithmIdentifier algid = (AlgorithmIdentifier) ai;
          return (algorithm.equals(algid.algorithm))
              && ((parameters == null)
                      ? algid.parameters == null
                      : Arrays.equals(parameters, algid.parameters));
      }
  
      @Override public int hashCode() {
          return algorithm.hashCode() * 37 + (parameters != null ? Arrays.hashCode(parameters) : 0);
      }
  
      public void dumpValue(StringBuilder sb) {
          sb.append(getAlgorithmName());
          if (parameters == null) {
              sb.append(", no params, ");
          } else {
              sb.append(", params unparsed, ");
          }
          sb.append("OID = ");
          sb.append(getAlgorithm());
      }
  
      /**
       * Custom AlgorithmIdentifier DER encoder/decoder
       */
      public static final ASN1Sequence ASN1 = new ASN1Sequence(new ASN1Type[] {
              ASN1Oid.getInstance(), ASN1Any.getInstance() }) {
          {
              setOptional(1); // parameters are optional
          }
  
          @Override protected Object getDecodedObject(BerInputStream in) {
              Object[] values = (Object[]) in.content;
              return new AlgorithmIdentifier(ObjectIdentifier
                      .toString((int[]) values[0]), (byte[]) values[1]);
          }
  
          @Override protected void getValues(Object object, Object[] values) {
  
              AlgorithmIdentifier aID = (AlgorithmIdentifier) object;
  
              values[0] = ObjectIdentifier.toIntArray(aID.getAlgorithm());
              values[1] = aID.getParameters();
          }
      };
  }
  