java.security.cert
Class X509CRL

java.lang.Object sample code for java.lang.Object definition code for java.lang.Object 
  extended by java.security.cert.CRL sample code for java.security.cert.CRL definition code for java.security.cert.CRL 
      extended by java.security.cert.X509CRL
All Implemented Interfaces:
X509Extension sample code for java.security.cert.X509Extension definition code for java.security.cert.X509Extension

public abstract class X509CRL
extends CRL sample code for java.security.cert.CRL definition code for java.security.cert.CRL
implements X509Extension sample code for java.security.cert.X509Extension definition code for java.security.cert.X509Extension

Abstract class for an X.509 Certificate Revocation List (CRL). A CRL is a time-stamped list identifying revoked certificates. It is signed by a Certificate Authority (CA) and made freely available in a public repository.

Each revoked certificate is identified in a CRL by its certificate serial number. When a certificate-using system uses a certificate (e.g., for verifying a remote user's digital signature), that system not only checks the certificate signature and validity but also acquires a suitably- recent CRL and checks that the certificate serial number is not on that CRL. The meaning of "suitably-recent" may vary with local policy, but it usually means the most recently-issued CRL. A CA issues a new CRL on a regular periodic basis (e.g., hourly, daily, or weekly). Entries are added to CRLs as revocations occur, and an entry may be removed when the certificate expiration date is reached.

The X.509 v2 CRL format is described below in ASN.1:

 CertificateList  ::=  SEQUENCE  {
     tbsCertList          TBSCertList,
     signatureAlgorithm   AlgorithmIdentifier,
     signature            BIT STRING  }
 

More information can be found in RFC 2459, "Internet X.509 Public Key Infrastructure Certificate and CRL Profile" at http://www.ietf.org/rfc/rfc2459.txt .

The ASN.1 definition of tbsCertList is:

 TBSCertList  ::=  SEQUENCE  {
     version                 Version OPTIONAL,
                             -- if present, must be v2
     signature               AlgorithmIdentifier,
     issuer                  Name,
     thisUpdate              ChoiceOfTime,
     nextUpdate              ChoiceOfTime OPTIONAL,
     revokedCertificates     SEQUENCE OF SEQUENCE  {
         userCertificate         CertificateSerialNumber,
         revocationDate          ChoiceOfTime,
         crlEntryExtensions      Extensions OPTIONAL
                                 -- if present, must be v2
         }  OPTIONAL,
     crlExtensions           [0]  EXPLICIT Extensions OPTIONAL
                                  -- if present, must be v2
     }
 

CRLs are instantiated using a certificate factory. The following is an example of how to instantiate an X.509 CRL:

 
 InputStream inStream = new FileInputStream("fileName-of-crl");
 CertificateFactory cf = CertificateFactory.getInstance("X.509");
 X509CRL crl = (X509CRL)cf.generateCRL(inStream);
 inStream.close();
 

See Also:
CRL sample code for java.security.cert.CRL definition code for java.security.cert.CRL , CertificateFactory sample code for java.security.cert.CertificateFactory definition code for java.security.cert.CertificateFactory , X509Extension sample code for java.security.cert.X509Extension definition code for java.security.cert.X509Extension

Constructor Summary
protected X509CRL sample code for java.security.cert.X509CRL.X509CRL() definition code for java.security.cert.X509CRL.X509CRL() ()
          Constructor for X.509 CRLs.
 
Method Summary
 boolean equals sample code for java.security.cert.X509CRL.equals(java.lang.Object) definition code for java.security.cert.X509CRL.equals(java.lang.Object) (Object sample code for java.lang.Object definition code for java.lang.Object  other)
          Compares this CRL for equality with the given object.
abstract  byte[] getEncoded sample code for java.security.cert.X509CRL.getEncoded() definition code for java.security.cert.X509CRL.getEncoded() ()
          Returns the ASN.1 DER-encoded form of this CRL.
abstract  Principal sample code for java.security.Principal definition code for java.security.Principal getIssuerDN sample code for java.security.cert.X509CRL.getIssuerDN() definition code for java.security.cert.X509CRL.getIssuerDN() ()
          Denigrated, replaced by getIssuerX500Principal() sample code for java.security.cert.X509CRL.getIssuerX500Principal() definition code for java.security.cert.X509CRL.getIssuerX500Principal() .
 X500Principal sample code for javax.security.auth.x500.X500Principal definition code for javax.security.auth.x500.X500Principal getIssuerX500Principal sample code for java.security.cert.X509CRL.getIssuerX500Principal() definition code for java.security.cert.X509CRL.getIssuerX500Principal() ()
          Returns the issuer (issuer distinguished name) value from the CRL as an X500Principal.
abstract  Date sample code for java.util.Date definition code for java.util.Date getNextUpdate sample code for java.security.cert.X509CRL.getNextUpdate() definition code for java.security.cert.X509CRL.getNextUpdate() ()
          Gets the nextUpdate date from the CRL.
abstract  X509CRLEntry sample code for java.security.cert.X509CRLEntry definition code for java.security.cert.X509CRLEntry getRevokedCertificate sample code for java.security.cert.X509CRL.getRevokedCertificate(java.math.BigInteger) definition code for java.security.cert.X509CRL.getRevokedCertificate(java.math.BigInteger) (BigInteger sample code for java.math.BigInteger definition code for java.math.BigInteger  serialNumber)
          Gets the CRL entry, if any, with the given certificate serialNumber.
 X509CRLEntry sample code for java.security.cert.X509CRLEntry definition code for java.security.cert.X509CRLEntry getRevokedCertificate sample code for java.security.cert.X509CRL.getRevokedCertificate(java.security.cert.X509Certificate) definition code for java.security.cert.X509CRL.getRevokedCertificate(java.security.cert.X509Certificate) (X509Certificate sample code for java.security.cert.X509Certificate definition code for java.security.cert.X509Certificate  certificate)
          Get the CRL entry, if any, for the given certificate.
abstract  Set sample code for java.util.Set definition code for java.util.Set <? extends X509CRLEntry sample code for java.security.cert.X509CRLEntry definition code for java.security.cert.X509CRLEntry > getRevokedCertificates sample code for java.security.cert.X509CRL.getRevokedCertificates() definition code for java.security.cert.X509CRL.getRevokedCertificates() ()
          Gets all the entries from this CRL.
abstract  String sample code for java.lang.String definition code for java.lang.String getSigAlgName sample code for java.security.cert.X509CRL.getSigAlgName() definition code for java.security.cert.X509CRL.getSigAlgName() ()
          Gets the signature algorithm name for the CRL signature algorithm.
abstract  String sample code for java.lang.String definition code for java.lang.String getSigAlgOID sample code for java.security.cert.X509CRL.getSigAlgOID() definition code for java.security.cert.X509CRL.getSigAlgOID() ()
          Gets the signature algorithm OID string from the CRL.
abstract  byte[] getSigAlgParams sample code for java.security.cert.X509CRL.getSigAlgParams() definition code for java.security.cert.X509CRL.getSigAlgParams() ()
          Gets the DER-encoded signature algorithm parameters from this CRL's signature algorithm.
abstract  byte[] getSignature sample code for java.security.cert.X509CRL.getSignature() definition code for java.security.cert.X509CRL.getSignature() ()
          Gets the signature value (the raw signature bits) from the CRL.
abstract  byte[] getTBSCertList sample code for java.security.cert.X509CRL.getTBSCertList() definition code for java.security.cert.X509CRL.getTBSCertList() ()
          Gets the DER-encoded CRL information, the tbsCertList from this CRL.
abstract  Date sample code for java.util.Date definition code for java.util.Date getThisUpdate sample code for java.security.cert.X509CRL.getThisUpdate() definition code for java.security.cert.X509CRL.getThisUpdate() ()
          Gets the thisUpdate date from the CRL.
abstract  int getVersion sample code for java.security.cert.X509CRL.getVersion() definition code for java.security.cert.X509CRL.getVersion() ()
          Gets the version (version number) value from the CRL.
 int hashCode sample code for java.security.cert.X509CRL.hashCode() definition code for java.security.cert.X509CRL.hashCode() ()
          Returns a hashcode value for this CRL from its encoded form.
abstract  void verify sample code for java.security.cert.X509CRL.verify(java.security.PublicKey) definition code for java.security.cert.X509CRL.verify(java.security.PublicKey) (PublicKey sample code for java.security.PublicKey definition code for java.security.PublicKey  key)
          Verifies that this CRL was signed using the private key that corresponds to the given public key.
abstract  void verify sample code for java.security.cert.X509CRL.verify(java.security.PublicKey, java.lang.String) definition code for java.security.cert.X509CRL.verify(java.security.PublicKey, java.lang.String) (PublicKey sample code for java.security.PublicKey definition code for java.security.PublicKey  key, String sample code for java.lang.String definition code for java.lang.String  sigProvider)
          Verifies that this CRL was signed using the private key that corresponds to the given public key.
 
Methods inherited from class java.security.cert.CRL sample code for java.security.cert.CRL definition code for java.security.cert.CRL
getType sample code for java.security.cert.CRL.getType() definition code for java.security.cert.CRL.getType() , isRevoked sample code for java.security.cert.CRL.isRevoked(java.security.cert.Certificate) definition code for java.security.cert.CRL.isRevoked(java.security.cert.Certificate) , toString sample code for java.security.cert.CRL.toString() definition code for java.security.cert.CRL.toString()
 
Methods inherited from class java.lang.Object sample code for java.lang.Object definition code for java.lang.Object
clone sample code for java.lang.Object.clone() definition code for java.lang.Object.clone() , finalize sample code for java.lang.Object.finalize() definition code for java.lang.Object.finalize() , getClass sample code for java.lang.Object.getClass() definition code for java.lang.Object.getClass() , notify sample code for java.lang.Object.notify() definition code for java.lang.Object.notify() , notifyAll sample code for java.lang.Object.notifyAll() definition code for java.lang.Object.notifyAll() , wait sample code for java.lang.Object.wait() definition code for java.lang.Object.wait() , wait sample code for java.lang.Object.wait(long) definition code for java.lang.Object.wait(long) , wait sample code for java.lang.Object.wait(long, int) definition code for java.lang.Object.wait(long, int)
 
Methods inherited from interface java.security.cert.X509Extension sample code for java.security.cert.X509Extension definition code for java.security.cert.X509Extension
getCriticalExtensionOIDs sample code for java.security.cert.X509Extension.getCriticalExtensionOIDs() definition code for java.security.cert.X509Extension.getCriticalExtensionOIDs() , getExtensionValue sample code for java.security.cert.X509Extension.getExtensionValue(java.lang.String) definition code for java.security.cert.X509Extension.getExtensionValue(java.lang.String) , getNonCriticalExtensionOIDs sample code for java.security.cert.X509Extension.getNonCriticalExtensionOIDs() definition code for java.security.cert.X509Extension.getNonCriticalExtensionOIDs() , hasUnsupportedCriticalExtension sample code for java.security.cert.X509Extension.hasUnsupportedCriticalExtension() definition code for java.security.cert.X509Extension.hasUnsupportedCriticalExtension()
 

Constructor Detail

X509CRL sample code for java.security.cert.X509CRL() definition code for java.security.cert.X509CRL()

protected X509CRL()
Constructor for X.509 CRLs.

Method Detail

equals sample code for java.security.cert.X509CRL.equals(java.lang.Object) definition code for java.security.cert.X509CRL.equals(java.lang.Object)

public boolean equals(Object sample code for java.lang.Object definition code for java.lang.Object  other)
Compares this CRL for equality with the given object. If the other object is an instanceof X509CRL, then its encoded form is retrieved and compared with the encoded form of this CRL.

Overrides:
equals sample code for java.lang.Object.equals(java.lang.Object) definition code for java.lang.Object.equals(java.lang.Object) in class Object sample code for java.lang.Object definition code for java.lang.Object
Parameters:
other - the object to test for equality with this CRL.
Returns:
true iff the encoded forms of the two CRLs match, false otherwise.
See Also:
Object.hashCode() sample code for java.lang.Object.hashCode() definition code for java.lang.Object.hashCode() , Hashtable sample code for java.util.Hashtable definition code for java.util.Hashtable

hashCode sample code for java.security.cert.X509CRL.hashCode() definition code for java.security.cert.X509CRL.hashCode()

public int hashCode()
Returns a hashcode value for this CRL from its encoded form.

Overrides:
hashCode sample code for java.lang.Object.hashCode() definition code for java.lang.Object.hashCode() in class Object sample code for java.lang.Object definition code for java.lang.Object
Returns:
the hashcode value.
See Also:
Object.equals(java.lang.Object) sample code for java.lang.Object.equals(java.lang.Object) definition code for java.lang.Object.equals(java.lang.Object) , Hashtable sample code for java.util.Hashtable definition code for java.util.Hashtable

getEncoded sample code for java.security.cert.X509CRL.getEncoded() definition code for java.security.cert.X509CRL.getEncoded()

public abstract byte[] getEncoded()
                           throws CRLException sample code for java.security.cert.CRLException definition code for java.security.cert.CRLException 
Returns the ASN.1 DER-encoded form of this CRL.

Returns:
the encoded form of this certificate
Throws:
CRLException sample code for java.security.cert.CRLException definition code for java.security.cert.CRLException - if an encoding error occurs.

verify sample code for java.security.cert.X509CRL.verify(java.security.PublicKey) definition code for java.security.cert.X509CRL.verify(java.security.PublicKey)

public abstract void verify(PublicKey sample code for java.security.PublicKey definition code for java.security.PublicKey  key)
                     throws CRLException sample code for java.security.cert.CRLException definition code for java.security.cert.CRLException ,
                            NoSuchAlgorithmException sample code for java.security.NoSuchAlgorithmException definition code for java.security.NoSuchAlgorithmException ,
                            InvalidKeyException sample code for java.security.InvalidKeyException definition code for java.security.InvalidKeyException ,
                            NoSuchProviderException sample code for java.security.NoSuchProviderException definition code for java.security.NoSuchProviderException ,
                            SignatureException sample code for java.security.SignatureException definition code for java.security.SignatureException 
Verifies that this CRL was signed using the private key that corresponds to the given public key.

Parameters:
key - the PublicKey used to carry out the verification.
Throws:
NoSuchAlgorithmException sample code for java.security.NoSuchAlgorithmException definition code for java.security.NoSuchAlgorithmException - on unsupported signature algorithms.
InvalidKeyException sample code for java.security.InvalidKeyException definition code for java.security.InvalidKeyException - on incorrect key.
NoSuchProviderException sample code for java.security.NoSuchProviderException definition code for java.security.NoSuchProviderException - if there's no default provider.
SignatureException sample code for java.security.SignatureException definition code for java.security.SignatureException - on signature errors.
CRLException sample code for java.security.cert.CRLException definition code for java.security.cert.CRLException - on encoding errors.

verify sample code for java.security.cert.X509CRL.verify(java.security.PublicKey, java.lang.String) definition code for java.security.cert.X509CRL.verify(java.security.PublicKey, java.lang.String)

public abstract void verify(PublicKey sample code for java.security.PublicKey definition code for java.security.PublicKey  key,
                            String sample code for java.lang.String definition code for java.lang.String  sigProvider)
                     throws CRLException sample code for java.security.cert.CRLException definition code for java.security.cert.CRLException ,
                            NoSuchAlgorithmException sample code for java.security.NoSuchAlgorithmException definition code for java.security.NoSuchAlgorithmException ,
                            InvalidKeyException sample code for java.security.InvalidKeyException definition code for java.security.InvalidKeyException ,
                            NoSuchProviderException sample code for java.security.NoSuchProviderException definition code for java.security.NoSuchProviderException ,
                            SignatureException sample code for java.security.SignatureException definition code for java.security.SignatureException 
Verifies that this CRL was signed using the private key that corresponds to the given public key. This method uses the signature verification engine supplied by the given provider.

Parameters:
key - the PublicKey used to carry out the verification.
sigProvider - the name of the signature provider.
Throws:
NoSuchAlgorithmException sample code for java.security.NoSuchAlgorithmException definition code for java.security.NoSuchAlgorithmException - on unsupported signature algorithms.
InvalidKeyException sample code for java.security.InvalidKeyException definition code for java.security.InvalidKeyException - on incorrect key.
NoSuchProviderException sample code for java.security.NoSuchProviderException definition code for java.security.NoSuchProviderException - on incorrect provider.
SignatureException sample code for java.security.SignatureException definition code for java.security.SignatureException - on signature errors.
CRLException sample code for java.security.cert.CRLException definition code for java.security.cert.CRLException - on encoding errors.

getVersion sample code for java.security.cert.X509CRL.getVersion() definition code for java.security.cert.X509CRL.getVersion()

public abstract int getVersion()
Gets the version (version number) value from the CRL. The ASN.1 definition for this is:
 version    Version OPTIONAL,
             -- if present, must be v2

Version ::= INTEGER { v1(0), v2(1), v3(2) } -- v3 does not apply to CRLs but appears for consistency -- with definition of Version for certs

Returns:
the version number, i.e. 1 or 2.

getIssuerDN sample code for java.security.cert.X509CRL.getIssuerDN() definition code for java.security.cert.X509CRL.getIssuerDN()

public abstract Principal sample code for java.security.Principal definition code for java.security.Principal  getIssuerDN()
Denigrated, replaced by getIssuerX500Principal() sample code for java.security.cert.X509CRL.getIssuerX500Principal() definition code for java.security.cert.X509CRL.getIssuerX500Principal() . This method returns the issuer as an implementation specific Principal object, which should not be relied upon by portable code.

Gets the issuer (issuer distinguished name) value from the CRL. The issuer name identifies the entity that signed (and issued) the CRL.

The issuer name field contains an X.500 distinguished name (DN). The ASN.1 definition for this is:

 issuer    Name

 Name ::= CHOICE { RDNSequence }
 RDNSequence ::= SEQUENCE OF RelativeDistinguishedName
 RelativeDistinguishedName ::=
     SET OF AttributeValueAssertion

 AttributeValueAssertion ::= SEQUENCE {
                               AttributeType,
                               AttributeValue }
 AttributeType ::= OBJECT IDENTIFIER
 AttributeValue ::= ANY
 
The Name describes a hierarchical name composed of attributes, such as country name, and corresponding values, such as US. The type of the AttributeValue component is determined by the AttributeType; in general it will be a directoryString. A directoryString is usually one of PrintableString, TeletexString or UniversalString.

Returns:
a Principal whose name is the issuer distinguished name.

getIssuerX500Principal sample code for java.security.cert.X509CRL.getIssuerX500Principal() definition code for java.security.cert.X509CRL.getIssuerX500Principal()

public X500Principal sample code for javax.security.auth.x500.X500Principal definition code for javax.security.auth.x500.X500Principal  getIssuerX500Principal()
Returns the issuer (issuer distinguished name) value from the CRL as an X500Principal.

It is recommended that subclasses override this method.

Returns:
an X500Principal representing the issuer distinguished name
Since:
1.4

getThisUpdate sample code for java.security.cert.X509CRL.getThisUpdate() definition code for java.security.cert.X509CRL.getThisUpdate()

public abstract Date sample code for java.util.Date definition code for java.util.Date  getThisUpdate()
Gets the thisUpdate date from the CRL. The ASN.1 definition for this is:
 thisUpdate   ChoiceOfTime
 ChoiceOfTime ::= CHOICE {
     utcTime        UTCTime,
     generalTime    GeneralizedTime }
 

Returns:
the thisUpdate date from the CRL.

getNextUpdate sample code for java.security.cert.X509CRL.getNextUpdate() definition code for java.security.cert.X509CRL.getNextUpdate()

public abstract Date sample code for java.util.Date definition code for java.util.Date  getNextUpdate()
Gets the nextUpdate date from the CRL.

Returns:
the nextUpdate date from the CRL, or null if not present.

getRevokedCertificate sample code for java.security.cert.X509CRL.getRevokedCertificate(java.math.BigInteger) definition code for java.security.cert.X509CRL.getRevokedCertificate(java.math.BigInteger)

public abstract X509CRLEntry sample code for java.security.cert.X509CRLEntry definition code for java.security.cert.X509CRLEntry  getRevokedCertificate(BigInteger sample code for java.math.BigInteger definition code for java.math.BigInteger  serialNumber)
Gets the CRL entry, if any, with the given certificate serialNumber.

Parameters:
serialNumber - the serial number of the certificate for which a CRL entry is to be looked up
Returns:
the entry with the given serial number, or null if no such entry exists in this CRL.
See Also:
X509CRLEntry sample code for java.security.cert.X509CRLEntry definition code for java.security.cert.X509CRLEntry

getRevokedCertificate sample code for java.security.cert.X509CRL.getRevokedCertificate(java.security.cert.X509Certificate) definition code for java.security.cert.X509CRL.getRevokedCertificate(java.security.cert.X509Certificate)

public X509CRLEntry sample code for java.security.cert.X509CRLEntry definition code for java.security.cert.X509CRLEntry  getRevokedCertificate(X509Certificate sample code for java.security.cert.X509Certificate definition code for java.security.cert.X509Certificate  certificate)
Get the CRL entry, if any, for the given certificate.

This method can be used to lookup CRL entries in indirect CRLs, that means CRLs that contain entries from issuers other than the CRL issuer. The default implementation will only return entries for certificates issued by the CRL issuer. Subclasses that wish to support indirect CRLs should override this method.

Parameters:
certificate - the certificate for which a CRL entry is to be looked up
Returns:
the entry for the given certificate, or null if no such entry exists in this CRL.
Throws:
NullPointerException sample code for java.lang.NullPointerException definition code for java.lang.NullPointerException - if certificate is null
Since:
1.5

getRevokedCertificates sample code for java.security.cert.X509CRL.getRevokedCertificates() definition code for java.security.cert.X509CRL.getRevokedCertificates()

public abstract Set sample code for java.util.Set definition code for java.util.Set <? extends X509CRLEntry sample code for java.security.cert.X509CRLEntry definition code for java.security.cert.X509CRLEntry > getRevokedCertificates()
Gets all the entries from this CRL. This returns a Set of X509CRLEntry objects.

Returns:
all the entries or null if there are none present.
See Also:
X509CRLEntry sample code for java.security.cert.X509CRLEntry definition code for java.security.cert.X509CRLEntry

getTBSCertList sample code for java.security.cert.X509CRL.getTBSCertList() definition code for java.security.cert.X509CRL.getTBSCertList()

public abstract byte[] getTBSCertList()
                               throws CRLException sample code for java.security.cert.CRLException definition code for java.security.cert.CRLException 
Gets the DER-encoded CRL information, the tbsCertList from this CRL. This can be used to verify the signature independently.

Returns:
the DER-encoded CRL information.
Throws:
CRLException sample code for java.security.cert.CRLException definition code for java.security.cert.CRLException - if an encoding error occurs.

getSignature sample code for java.security.cert.X509CRL.getSignature() definition code for java.security.cert.X509CRL.getSignature()

public abstract byte[] getSignature()
Gets the signature value (the raw signature bits) from the CRL. The ASN.1 definition for this is:
 signature     BIT STRING  
 

Returns:
the signature.

getSigAlgName sample code for java.security.cert.X509CRL.getSigAlgName() definition code for java.security.cert.X509CRL.getSigAlgName()

public abstract String sample code for java.lang.String definition code for java.lang.String  getSigAlgName()
Gets the signature algorithm name for the CRL signature algorithm. An example is the string "SHA-1/DSA". The ASN.1 definition for this is:
 signatureAlgorithm   AlgorithmIdentifier

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

The algorithm name is determined from the algorithm OID string.

Returns:
the signature algorithm name.

getSigAlgOID sample code for java.security.cert.X509CRL.getSigAlgOID() definition code for java.security.cert.X509CRL.getSigAlgOID()

public abstract String sample code for java.lang.String definition code for java.lang.String  getSigAlgOID()
Gets the signature algorithm OID string from the CRL. 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, as per RFC 2459.

See getSigAlgName sample code for java.security.cert.X509CRL.getSigAlgName() definition code for java.security.cert.X509CRL.getSigAlgName() for relevant ASN.1 definitions.

Returns:
the signature algorithm OID string.

getSigAlgParams sample code for java.security.cert.X509CRL.getSigAlgParams() definition code for java.security.cert.X509CRL.getSigAlgParams()

public abstract byte[] getSigAlgParams()
Gets the DER-encoded signature algorithm parameters from this CRL's signature algorithm. In most cases, the signature algorithm parameters are null; the parameters are usually supplied with the public key. If access to individual parameter values is needed then use AlgorithmParameters sample code for java.security.AlgorithmParameters definition code for java.security.AlgorithmParameters and instantiate with the name returned by getSigAlgName sample code for java.security.cert.X509CRL.getSigAlgName() definition code for java.security.cert.X509CRL.getSigAlgName() .

See getSigAlgName sample code for java.security.cert.X509CRL.getSigAlgName() definition code for java.security.cert.X509CRL.getSigAlgName() for relevant ASN.1 definitions.

Returns:
the DER-encoded signature algorithm parameters, or null if no parameters are present.