--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/security/cert/X509Certificate.java Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,649 @@
+/*
+ * Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.security.cert;
+
+import java.math.BigInteger;
+import java.security.Principal;
+import java.security.PublicKey;
+import java.util.Collection;
+import java.util.Date;
+import java.util.List;
+import javax.security.auth.x500.X500Principal;
+
+import sun.security.x509.X509CertImpl;
+
+/**
+ * <p>
+ * Abstract class for X.509 certificates. This provides a standard
+ * way to access all the attributes of an X.509 certificate.
+ * <p>
+ * In June of 1996, the basic X.509 v3 format was completed by
+ * ISO/IEC and ANSI X9, which is described below in ASN.1:
+ * <pre>
+ * Certificate ::= SEQUENCE {
+ * tbsCertificate TBSCertificate,
+ * signatureAlgorithm AlgorithmIdentifier,
+ * signature BIT STRING }
+ * </pre>
+ * <p>
+ * These certificates are widely used to support authentication and
+ * other functionality in Internet security systems. Common applications
+ * include Privacy Enhanced Mail (PEM), Transport Layer Security (SSL),
+ * code signing for trusted software distribution, and Secure Electronic
+ * Transactions (SET).
+ * <p>
+ * These certificates are managed and vouched for by <em>Certificate
+ * Authorities</em> (CAs). CAs are services which create certificates by
+ * placing data in the X.509 standard format and then digitally signing
+ * that data. CAs act as trusted third parties, making introductions
+ * between principals who have no direct knowledge of each other.
+ * CA certificates are either signed by themselves, or by some other
+ * CA such as a "root" CA.
+ * <p>
+ * More information can be found in
+ * <a href="http://www.ietf.org/rfc/rfc3280.txt">RFC 3280: Internet X.509
+ * Public Key Infrastructure Certificate and CRL Profile</a>.
+ * <p>
+ * The ASN.1 definition of <code>tbsCertificate</code> is:
+ * <pre>
+ * TBSCertificate ::= SEQUENCE {
+ * version [0] EXPLICIT Version DEFAULT v1,
+ * serialNumber CertificateSerialNumber,
+ * signature AlgorithmIdentifier,
+ * issuer Name,
+ * validity Validity,
+ * subject Name,
+ * subjectPublicKeyInfo SubjectPublicKeyInfo,
+ * issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
+ * -- If present, version must be v2 or v3
+ * subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
+ * -- If present, version must be v2 or v3
+ * extensions [3] EXPLICIT Extensions OPTIONAL
+ * -- If present, version must be v3
+ * }
+ * </pre>
+ * <p>
+ * Certificates are instantiated using a certificate factory. The following is
+ * an example of how to instantiate an X.509 certificate:
+ * <pre>
+ * InputStream inStream = null;
+ * try {
+ * inStream = new FileInputStream("fileName-of-cert");
+ * CertificateFactory cf = CertificateFactory.getInstance("X.509");
+ * X509Certificate cert = (X509Certificate)cf.generateCertificate(inStream);
+ * } finally {
+ * if (inStream != null) {
+ * inStream.close();
+ * }
+ * }
+ * </pre>
+ *
+ * @author Hemma Prafullchandra
+ *
+ *
+ * @see Certificate
+ * @see CertificateFactory
+ * @see X509Extension
+ */
+
+public abstract class X509Certificate extends Certificate
+implements X509Extension {
+
+ private static final long serialVersionUID = -2491127588187038216L;
+
+ private transient X500Principal subjectX500Principal, issuerX500Principal;
+
+ /**
+ * Constructor for X.509 certificates.
+ */
+ protected X509Certificate() {
+ super("X.509");
+ }
+
+ /**
+ * Checks that the certificate is currently valid. It is if
+ * the current date and time are within the validity period given in the
+ * certificate.
+ * <p>
+ * The validity period consists of two date/time values:
+ * the first and last dates (and times) on which the certificate
+ * is valid. It is defined in
+ * ASN.1 as:
+ * <pre>
+ * validity Validity<p>
+ * Validity ::= SEQUENCE {
+ * notBefore CertificateValidityDate,
+ * notAfter CertificateValidityDate }<p>
+ * CertificateValidityDate ::= CHOICE {
+ * utcTime UTCTime,
+ * generalTime GeneralizedTime }
+ * </pre>
+ *
+ * @exception CertificateExpiredException if the certificate has expired.
+ * @exception CertificateNotYetValidException if the certificate is not
+ * yet valid.
+ */
+ public abstract void checkValidity()
+ throws CertificateExpiredException, CertificateNotYetValidException;
+
+ /**
+ * Checks that the given date is within the certificate's
+ * validity period. In other words, this determines whether the
+ * certificate would be valid at the given date/time.
+ *
+ * @param date the Date to check against to see if this certificate
+ * is valid at that date/time.
+ *
+ * @exception CertificateExpiredException if the certificate has expired
+ * with respect to the <code>date</code> supplied.
+ * @exception CertificateNotYetValidException if the certificate is not
+ * yet valid with respect to the <code>date</code> supplied.
+ *
+ * @see #checkValidity()
+ */
+ public abstract void checkValidity(Date date)
+ throws CertificateExpiredException, CertificateNotYetValidException;
+
+ /**
+ * Gets the <code>version</code> (version number) value from the
+ * certificate.
+ * The ASN.1 definition for this is:
+ * <pre>
+ * version [0] EXPLICIT Version DEFAULT v1<p>
+ * Version ::= INTEGER { v1(0), v2(1), v3(2) }
+ * </pre>
+ * @return the version number, i.e. 1, 2 or 3.
+ */
+ public abstract int getVersion();
+
+ /**
+ * Gets the <code>serialNumber</code> value from the certificate.
+ * The serial number is an integer assigned by the certification
+ * authority to each certificate. It must be unique for each
+ * certificate issued by a given CA (i.e., the issuer name and
+ * serial number identify a unique certificate).
+ * The ASN.1 definition for this is:
+ * <pre>
+ * serialNumber CertificateSerialNumber<p>
+ *
+ * CertificateSerialNumber ::= INTEGER
+ * </pre>
+ *
+ * @return the serial number.
+ */
+ public abstract BigInteger getSerialNumber();
+
+ /**
+ * <strong>Denigrated</strong>, replaced by {@linkplain
+ * #getIssuerX500Principal()}. This method returns the <code>issuer</code>
+ * as an implementation specific Principal object, which should not be
+ * relied upon by portable code.
+ *
+ * <p>
+ * Gets the <code>issuer</code> (issuer distinguished name) value from
+ * the certificate. The issuer name identifies the entity that signed (and
+ * issued) the certificate.
+ *
+ * <p>The issuer name field contains an
+ * X.500 distinguished name (DN).
+ * The ASN.1 definition for this is:
+ * <pre>
+ * issuer Name<p>
+ *
+ * Name ::= CHOICE { RDNSequence }
+ * RDNSequence ::= SEQUENCE OF RelativeDistinguishedName
+ * RelativeDistinguishedName ::=
+ * SET OF AttributeValueAssertion
+ *
+ * AttributeValueAssertion ::= SEQUENCE {
+ * AttributeType,
+ * AttributeValue }
+ * AttributeType ::= OBJECT IDENTIFIER
+ * AttributeValue ::= ANY
+ * </pre>
+ * The <code>Name</code> describes a hierarchical name composed of
+ * attributes,
+ * such as country name, and corresponding values, such as US.
+ * The type of the <code>AttributeValue</code> component is determined by
+ * the <code>AttributeType</code>; in general it will be a
+ * <code>directoryString</code>. A <code>directoryString</code> is usually
+ * one of <code>PrintableString</code>,
+ * <code>TeletexString</code> or <code>UniversalString</code>.
+ *
+ * @return a Principal whose name is the issuer distinguished name.
+ */
+ public abstract Principal getIssuerDN();
+
+ /**
+ * Returns the issuer (issuer distinguished name) value from the
+ * certificate as an <code>X500Principal</code>.
+ * <p>
+ * It is recommended that subclasses override this method.
+ *
+ * @return an <code>X500Principal</code> representing the issuer
+ * distinguished name
+ * @since 1.4
+ */
+ public X500Principal getIssuerX500Principal() {
+ if (issuerX500Principal == null) {
+ issuerX500Principal = X509CertImpl.getIssuerX500Principal(this);
+ }
+ return issuerX500Principal;
+ }
+
+ /**
+ * <strong>Denigrated</strong>, replaced by {@linkplain
+ * #getSubjectX500Principal()}. This method returns the <code>subject</code>
+ * as an implementation specific Principal object, which should not be
+ * relied upon by portable code.
+ *
+ * <p>
+ * Gets the <code>subject</code> (subject distinguished name) value
+ * from the certificate. If the <code>subject</code> value is empty,
+ * then the <code>getName()</code> method of the returned
+ * <code>Principal</code> object returns an empty string ("").
+ *
+ * <p> The ASN.1 definition for this is:
+ * <pre>
+ * subject Name
+ * </pre>
+ *
+ * <p>See {@link #getIssuerDN() getIssuerDN} for <code>Name</code>
+ * and other relevant definitions.
+ *
+ * @return a Principal whose name is the subject name.
+ */
+ public abstract Principal getSubjectDN();
+
+ /**
+ * Returns the subject (subject distinguished name) value from the
+ * certificate as an <code>X500Principal</code>. If the subject value
+ * is empty, then the <code>getName()</code> method of the returned
+ * <code>X500Principal</code> object returns an empty string ("").
+ * <p>
+ * It is recommended that subclasses override this method.
+ *
+ * @return an <code>X500Principal</code> representing the subject
+ * distinguished name
+ * @since 1.4
+ */
+ public X500Principal getSubjectX500Principal() {
+ if (subjectX500Principal == null) {
+ subjectX500Principal = X509CertImpl.getSubjectX500Principal(this);
+ }
+ return subjectX500Principal;
+ }
+
+ /**
+ * Gets the <code>notBefore</code> date from the validity period of
+ * the certificate.
+ * The relevant ASN.1 definitions are:
+ * <pre>
+ * validity Validity<p>
+ *
+ * Validity ::= SEQUENCE {
+ * notBefore CertificateValidityDate,
+ * notAfter CertificateValidityDate }<p>
+ * CertificateValidityDate ::= CHOICE {
+ * utcTime UTCTime,
+ * generalTime GeneralizedTime }
+ * </pre>
+ *
+ * @return the start date of the validity period.
+ * @see #checkValidity
+ */
+ public abstract Date getNotBefore();
+
+ /**
+ * Gets the <code>notAfter</code> date from the validity period of
+ * the certificate. See {@link #getNotBefore() getNotBefore}
+ * for relevant ASN.1 definitions.
+ *
+ * @return the end date of the validity period.
+ * @see #checkValidity
+ */
+ public abstract Date getNotAfter();
+
+ /**
+ * Gets the DER-encoded certificate information, the
+ * <code>tbsCertificate</code> from this certificate.
+ * This can be used to verify the signature independently.
+ *
+ * @return the DER-encoded certificate information.
+ * @exception CertificateEncodingException if an encoding error occurs.
+ */
+ public abstract byte[] getTBSCertificate()
+ throws CertificateEncodingException;
+
+ /**
+ * Gets the <code>signature</code> value (the raw signature bits) from
+ * the certificate.
+ * The ASN.1 definition for this is:
+ * <pre>
+ * signature BIT STRING
+ * </pre>
+ *
+ * @return the signature.
+ */
+ public abstract byte[] getSignature();
+
+ /**
+ * Gets the signature algorithm name for the certificate
+ * signature algorithm. An example is the string "SHA-1/DSA".
+ * The ASN.1 definition for this is:
+ * <pre>
+ * signatureAlgorithm AlgorithmIdentifier<p>
+ * AlgorithmIdentifier ::= SEQUENCE {
+ * algorithm OBJECT IDENTIFIER,
+ * parameters ANY DEFINED BY algorithm OPTIONAL }
+ * -- contains a value of the type
+ * -- registered for use with the
+ * -- algorithm object identifier value
+ * </pre>
+ *
+ * <p>The algorithm name is determined from the <code>algorithm</code>
+ * OID string.
+ *
+ * @return the signature algorithm name.
+ */
+ public abstract String getSigAlgName();
+
+ /**
+ * Gets the signature algorithm OID string from the certificate.
+ * An OID is represented by a set of nonnegative whole numbers separated
+ * by periods.
+ * For example, the string "1.2.840.10040.4.3" identifies the SHA-1
+ * with DSA signature algorithm defined in
+ * <a href="http://www.ietf.org/rfc/rfc3279.txt">RFC 3279: Algorithms and
+ * Identifiers for the Internet X.509 Public Key Infrastructure Certificate
+ * and CRL Profile</a>.
+ *
+ * <p>See {@link #getSigAlgName() getSigAlgName} for
+ * relevant ASN.1 definitions.
+ *
+ * @return the signature algorithm OID string.
+ */
+ public abstract String getSigAlgOID();
+
+ /**
+ * Gets the DER-encoded signature algorithm parameters from this
+ * certificate's signature algorithm. In most cases, the signature
+ * algorithm parameters are null; the parameters are usually
+ * supplied with the certificate's public key.
+ * If access to individual parameter values is needed then use
+ * {@link java.security.AlgorithmParameters AlgorithmParameters}
+ * and instantiate with the name returned by
+ * {@link #getSigAlgName() getSigAlgName}.
+ *
+ * <p>See {@link #getSigAlgName() getSigAlgName} for
+ * relevant ASN.1 definitions.
+ *
+ * @return the DER-encoded signature algorithm parameters, or
+ * null if no parameters are present.
+ */
+ public abstract byte[] getSigAlgParams();
+
+ /**
+ * Gets the <code>issuerUniqueID</code> value from the certificate.
+ * The issuer unique identifier is present in the certificate
+ * to handle the possibility of reuse of issuer names over time.
+ * RFC 3280 recommends that names not be reused and that
+ * conforming certificates not make use of unique identifiers.
+ * Applications conforming to that profile should be capable of
+ * parsing unique identifiers and making comparisons.
+ *
+ * <p>The ASN.1 definition for this is:
+ * <pre>
+ * issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL<p>
+ * UniqueIdentifier ::= BIT STRING
+ * </pre>
+ *
+ * @return the issuer unique identifier or null if it is not
+ * present in the certificate.
+ */
+ public abstract boolean[] getIssuerUniqueID();
+
+ /**
+ * Gets the <code>subjectUniqueID</code> value from the certificate.
+ *
+ * <p>The ASN.1 definition for this is:
+ * <pre>
+ * subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL<p>
+ * UniqueIdentifier ::= BIT STRING
+ * </pre>
+ *
+ * @return the subject unique identifier or null if it is not
+ * present in the certificate.
+ */
+ public abstract boolean[] getSubjectUniqueID();
+
+ /**
+ * Gets a boolean array representing bits of
+ * the <code>KeyUsage</code> extension, (OID = 2.5.29.15).
+ * The key usage extension defines the purpose (e.g., encipherment,
+ * signature, certificate signing) of the key contained in the
+ * certificate.
+ * The ASN.1 definition for this is:
+ * <pre>
+ * KeyUsage ::= BIT STRING {
+ * digitalSignature (0),
+ * nonRepudiation (1),
+ * keyEncipherment (2),
+ * dataEncipherment (3),
+ * keyAgreement (4),
+ * keyCertSign (5),
+ * cRLSign (6),
+ * encipherOnly (7),
+ * decipherOnly (8) }
+ * </pre>
+ * RFC 3280 recommends that when used, this be marked
+ * as a critical extension.
+ *
+ * @return the KeyUsage extension of this certificate, represented as
+ * an array of booleans. The order of KeyUsage values in the array is
+ * the same as in the above ASN.1 definition. The array will contain a
+ * value for each KeyUsage defined above. If the KeyUsage list encoded
+ * in the certificate is longer than the above list, it will not be
+ * truncated. Returns null if this certificate does not
+ * contain a KeyUsage extension.
+ */
+ public abstract boolean[] getKeyUsage();
+
+ /**
+ * Gets an unmodifiable list of Strings representing the OBJECT
+ * IDENTIFIERs of the <code>ExtKeyUsageSyntax</code> field of the
+ * extended key usage extension, (OID = 2.5.29.37). It indicates
+ * one or more purposes for which the certified public key may be
+ * used, in addition to or in place of the basic purposes
+ * indicated in the key usage extension field. The ASN.1
+ * definition for this is:
+ * <pre>
+ * ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId<p>
+ *
+ * KeyPurposeId ::= OBJECT IDENTIFIER<p>
+ * </pre>
+ *
+ * Key purposes may be defined by any organization with a
+ * need. Object identifiers used to identify key purposes shall be
+ * assigned in accordance with IANA or ITU-T Rec. X.660 |
+ * ISO/IEC/ITU 9834-1.
+ * <p>
+ * This method was added to version 1.4 of the Java 2 Platform Standard
+ * Edition. In order to maintain backwards compatibility with existing
+ * service providers, this method is not <code>abstract</code>
+ * and it provides a default implementation. Subclasses
+ * should override this method with a correct implementation.
+ *
+ * @return the ExtendedKeyUsage extension of this certificate,
+ * as an unmodifiable list of object identifiers represented
+ * as Strings. Returns null if this certificate does not
+ * contain an ExtendedKeyUsage extension.
+ * @throws CertificateParsingException if the extension cannot be decoded
+ * @since 1.4
+ */
+ public List<String> getExtendedKeyUsage() throws CertificateParsingException {
+ return X509CertImpl.getExtendedKeyUsage(this);
+ }
+
+ /**
+ * Gets the certificate constraints path length from the
+ * critical <code>BasicConstraints</code> extension, (OID = 2.5.29.19).
+ * <p>
+ * The basic constraints extension identifies whether the subject
+ * of the certificate is a Certificate Authority (CA) and
+ * how deep a certification path may exist through that CA. The
+ * <code>pathLenConstraint</code> field (see below) is meaningful
+ * only if <code>cA</code> is set to TRUE. In this case, it gives the
+ * maximum number of CA certificates that may follow this certificate in a
+ * certification path. A value of zero indicates that only an end-entity
+ * certificate may follow in the path.
+ * <p>
+ * The ASN.1 definition for this is:
+ * <pre>
+ * BasicConstraints ::= SEQUENCE {
+ * cA BOOLEAN DEFAULT FALSE,
+ * pathLenConstraint INTEGER (0..MAX) OPTIONAL }
+ * </pre>
+ *
+ * @return the value of <code>pathLenConstraint</code> if the
+ * BasicConstraints extension is present in the certificate and the
+ * subject of the certificate is a CA, otherwise -1.
+ * If the subject of the certificate is a CA and
+ * <code>pathLenConstraint</code> does not appear,
+ * <code>Integer.MAX_VALUE</code> is returned to indicate that there is no
+ * limit to the allowed length of the certification path.
+ */
+ public abstract int getBasicConstraints();
+
+ /**
+ * Gets an immutable collection of subject alternative names from the
+ * <code>SubjectAltName</code> extension, (OID = 2.5.29.17).
+ * <p>
+ * The ASN.1 definition of the <code>SubjectAltName</code> extension is:
+ * <pre>
+ * SubjectAltName ::= GeneralNames
+ *
+ * GeneralNames :: = SEQUENCE SIZE (1..MAX) OF GeneralName
+ *
+ * GeneralName ::= CHOICE {
+ * otherName [0] OtherName,
+ * rfc822Name [1] IA5String,
+ * dNSName [2] IA5String,
+ * x400Address [3] ORAddress,
+ * directoryName [4] Name,
+ * ediPartyName [5] EDIPartyName,
+ * uniformResourceIdentifier [6] IA5String,
+ * iPAddress [7] OCTET STRING,
+ * registeredID [8] OBJECT IDENTIFIER}
+ * </pre>
+ * <p>
+ * If this certificate does not contain a <code>SubjectAltName</code>
+ * extension, <code>null</code> is returned. Otherwise, a
+ * <code>Collection</code> is returned with an entry representing each
+ * <code>GeneralName</code> included in the extension. Each entry is a
+ * <code>List</code> whose first entry is an <code>Integer</code>
+ * (the name type, 0-8) and whose second entry is a <code>String</code>
+ * or a byte array (the name, in string or ASN.1 DER encoded form,
+ * respectively).
+ * <p>
+ * <a href="http://www.ietf.org/rfc/rfc822.txt">RFC 822</a>, DNS, and URI
+ * names are returned as <code>String</code>s,
+ * using the well-established string formats for those types (subject to
+ * the restrictions included in RFC 3280). IPv4 address names are
+ * returned using dotted quad notation. IPv6 address names are returned
+ * in the form "a1:a2:...:a8", where a1-a8 are hexadecimal values
+ * representing the eight 16-bit pieces of the address. OID names are
+ * returned as <code>String</code>s represented as a series of nonnegative
+ * integers separated by periods. And directory names (distinguished names)
+ * are returned in <a href="http://www.ietf.org/rfc/rfc2253.txt">
+ * RFC 2253</a> string format. No standard string format is
+ * defined for otherNames, X.400 names, EDI party names, or any
+ * other type of names. They are returned as byte arrays
+ * containing the ASN.1 DER encoded form of the name.
+ * <p>
+ * Note that the <code>Collection</code> returned may contain more
+ * than one name of the same type. Also, note that the returned
+ * <code>Collection</code> is immutable and any entries containing byte
+ * arrays are cloned to protect against subsequent modifications.
+ * <p>
+ * This method was added to version 1.4 of the Java 2 Platform Standard
+ * Edition. In order to maintain backwards compatibility with existing
+ * service providers, this method is not <code>abstract</code>
+ * and it provides a default implementation. Subclasses
+ * should override this method with a correct implementation.
+ *
+ * @return an immutable <code>Collection</code> of subject alternative
+ * names (or <code>null</code>)
+ * @throws CertificateParsingException if the extension cannot be decoded
+ * @since 1.4
+ */
+ public Collection<List<?>> getSubjectAlternativeNames()
+ throws CertificateParsingException {
+ return X509CertImpl.getSubjectAlternativeNames(this);
+ }
+
+ /**
+ * Gets an immutable collection of issuer alternative names from the
+ * <code>IssuerAltName</code> extension, (OID = 2.5.29.18).
+ * <p>
+ * The ASN.1 definition of the <code>IssuerAltName</code> extension is:
+ * <pre>
+ * IssuerAltName ::= GeneralNames
+ * </pre>
+ * The ASN.1 definition of <code>GeneralNames</code> is defined
+ * in {@link #getSubjectAlternativeNames getSubjectAlternativeNames}.
+ * <p>
+ * If this certificate does not contain an <code>IssuerAltName</code>
+ * extension, <code>null</code> is returned. Otherwise, a
+ * <code>Collection</code> is returned with an entry representing each
+ * <code>GeneralName</code> included in the extension. Each entry is a
+ * <code>List</code> whose first entry is an <code>Integer</code>
+ * (the name type, 0-8) and whose second entry is a <code>String</code>
+ * or a byte array (the name, in string or ASN.1 DER encoded form,
+ * respectively). For more details about the formats used for each
+ * name type, see the <code>getSubjectAlternativeNames</code> method.
+ * <p>
+ * Note that the <code>Collection</code> returned may contain more
+ * than one name of the same type. Also, note that the returned
+ * <code>Collection</code> is immutable and any entries containing byte
+ * arrays are cloned to protect against subsequent modifications.
+ * <p>
+ * This method was added to version 1.4 of the Java 2 Platform Standard
+ * Edition. In order to maintain backwards compatibility with existing
+ * service providers, this method is not <code>abstract</code>
+ * and it provides a default implementation. Subclasses
+ * should override this method with a correct implementation.
+ *
+ * @return an immutable <code>Collection</code> of issuer alternative
+ * names (or <code>null</code>)
+ * @throws CertificateParsingException if the extension cannot be decoded
+ * @since 1.4
+ */
+ public Collection<List<?>> getIssuerAlternativeNames()
+ throws CertificateParsingException {
+ return X509CertImpl.getIssuerAlternativeNames(this);
+ }
+}