The basic X.509 format was defined by ISO/IEC and ANSI X9 and is described below in ASN.1:
 Certificate  ::=  SEQUENCE  {
     tbsCertificate       TBSCertificate,
     signatureAlgorithm   AlgorithmIdentifier,
     signature            BIT STRING  }
 
 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).
These certificates are managed and vouched for by Certificate Authorities (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.
 The ASN.1 definition of tbsCertificate is:
 
 TBSCertificate  ::=  SEQUENCE  {
     version         [0]  EXPLICIT Version DEFAULT v1,
     serialNumber         CertificateSerialNumber,
     signature            AlgorithmIdentifier,
     issuer               Name,
     validity             Validity,
     subject              Name,
     subjectPublicKeyInfo SubjectPublicKeyInfo,
     }
 
 Here is sample code to instantiate an X.509 certificate:
 InputStream inStream = new FileInputStream("fileName-of-cert");
 X509Certificate cert = X509Certificate.getInstance(inStream);
 inStream.close();
 
 OR
 byte[] certData = <certificate read from a file, say> X509Certificate cert = X509Certificate.getInstance(certData);
 In either case, the code that instantiates an X.509 certificate
 consults the value of the cert.provider.x509v1 security property
 to locate the actual implementation or instantiates a default implementation.
 
 The cert.provider.x509v1 property is set to a default
 implementation for X.509 such as:
 
cert.provider.x509v1=com.sun.security.cert.internal.x509.X509V1CertImpl
 The value of this cert.provider.x509v1 property has to be
 changed to instantiate another implementation. If this security
 property is not set, a default implementation will be used.
 Currently, due to possible security restrictions on access to
 Security properties, this value is looked up and cached at class
 initialization time and will fallback on a default implementation if
 the Security property is not accessible.
 
Note: The classes in the package javax.security.cert
 exist for compatibility with earlier versions of the
 Java Secure Sockets Extension (JSSE). New applications should instead
 use the standard Java SE certificate classes located in
 java.security.cert.
- Since:
- 1.4
- See Also:
- 
Constructor SummaryConstructorsConstructorDescriptionDeprecated, for removal: This API element is subject to removal in a future version.Constructor for subclasses to call.
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Method SummaryModifier and TypeMethodDescriptionabstract voidDeprecated, for removal: This API element is subject to removal in a future version.Checks that the certificate is currently valid.abstract voidcheckValidity(Date date) Deprecated, for removal: This API element is subject to removal in a future version.Checks that the specified date is within the certificate's validity period.static final X509CertificategetInstance(byte[] certData) Deprecated, for removal: This API element is subject to removal in a future version.Instantiates an X509Certificate object, and initializes it with the specified byte array.static final X509CertificategetInstance(InputStream inStream) Deprecated, for removal: This API element is subject to removal in a future version.Instantiates an X509Certificate object, and initializes it with the data read from the input streaminStream.abstract PrincipalDeprecated, for removal: This API element is subject to removal in a future version.Gets theissuer(issuer distinguished name) value from the certificate.abstract DateDeprecated, for removal: This API element is subject to removal in a future version.Gets thenotAfterdate from the validity period of the certificate.abstract DateDeprecated, for removal: This API element is subject to removal in a future version.Gets thenotBeforedate from the validity period of the certificate.abstract BigIntegerDeprecated, for removal: This API element is subject to removal in a future version.Gets theserialNumbervalue from the certificate.abstract StringDeprecated, for removal: This API element is subject to removal in a future version.Gets the signature algorithm name for the certificate signature algorithm.abstract StringDeprecated, for removal: This API element is subject to removal in a future version.Gets the signature algorithm OID string from the certificate.abstract byte[]Deprecated, for removal: This API element is subject to removal in a future version.Gets the DER-encoded signature algorithm parameters from this certificate's signature algorithm.abstract PrincipalDeprecated, for removal: This API element is subject to removal in a future version.Gets thesubject(subject distinguished name) value from the certificate.abstract intDeprecated, for removal: This API element is subject to removal in a future version.Gets theversion(version number) value from the certificate.Methods declared in class javax.security.cert.Certificateequals, getEncoded, getPublicKey, hashCode, toString, verify, verify
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Constructor Details- 
X509Certificatepublic X509Certificate()Deprecated, for removal: This API element is subject to removal in a future version.Constructor for subclasses to call.
 
- 
- 
Method Details- 
getInstanceDeprecated, for removal: This API element is subject to removal in a future version.Instantiates an X509Certificate object, and initializes it with the data read from the input streaminStream. The implementation (X509Certificate is an abstract class) is provided by the class specified as the value of thecert.provider.x509v1security property.Note: Only one DER-encoded certificate is expected to be in the input stream. Also, all X509Certificate subclasses must provide a constructor of the form: public <subClass>(InputStream inStream) ...- Parameters:
- inStream- an input stream with the data to be read to initialize the certificate.
- Returns:
- an X509Certificate object initialized with the data from the input stream.
- Throws:
- CertificateException- if a class initialization or certificate parsing error occurs.
 
- 
getInstanceDeprecated, for removal: This API element is subject to removal in a future version.Instantiates an X509Certificate object, and initializes it with the specified byte array. The implementation (X509Certificate is an abstract class) is provided by the class specified as the value of thecert.provider.x509v1security property.Note: All X509Certificate subclasses must provide a constructor of the form: public <subClass>(InputStream inStream) ...- Parameters:
- certData- a byte array containing the DER-encoded certificate.
- Returns:
- an X509Certificate object initialized with the data
         from certData.
- Throws:
- CertificateException- if a class initialization or certificate parsing error occurs.
 
- 
checkValiditypublic abstract void checkValidity() throws CertificateExpiredException, CertificateNotYetValidExceptionDeprecated, for removal: This API element is subject to removal in a future version.Checks that the certificate is currently valid. It is if the current date and time are within the validity period given in the certificate.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: validity Validity Validity ::= SEQUENCE { notBefore CertificateValidityDate, notAfter CertificateValidityDate } CertificateValidityDate ::= CHOICE { utcTime UTCTime, generalTime GeneralizedTime }- Throws:
- CertificateExpiredException- if the certificate has expired.
- CertificateNotYetValidException- if the certificate is not yet valid.
 
- 
checkValiditypublic abstract void checkValidity(Date date) throws CertificateExpiredException, CertificateNotYetValidException Deprecated, for removal: This API element is subject to removal in a future version.Checks that the specified date is within the certificate's validity period. In other words, this determines whether the certificate would be valid at the specified date/time.- Parameters:
- date- the Date to check against to see if this certificate is valid at that date/time.
- Throws:
- CertificateExpiredException- if the certificate has expired with respect to the- datesupplied.
- CertificateNotYetValidException- if the certificate is not yet valid with respect to the- datesupplied.
- See Also:
 
- 
getVersionpublic abstract int getVersion()Deprecated, for removal: This API element is subject to removal in a future version.Gets theversion(version number) value from the certificate. The ASN.1 definition for this is:version [0] EXPLICIT Version DEFAULT v1 Version ::= INTEGER { v1(0), v2(1), v3(2) }- Returns:
- the version number from the ASN.1 encoding, i.e. 0, 1 or 2.
 
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getSerialNumberDeprecated, for removal: This API element is subject to removal in a future version.Gets theserialNumbervalue 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:serialNumber CertificateSerialNumber CertificateSerialNumber ::= INTEGER - Returns:
- the serial number.
 
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getIssuerDNDeprecated, for removal: This API element is subject to removal in a future version.Gets theissuer(issuer distinguished name) value from the certificate. The issuer name identifies the entity that signed (and issued) the certificate.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 ::= ANYTheNamedescribes a hierarchical name composed of attributes, such as country name, and corresponding values, such as US. The type of theAttributeValuecomponent is determined by theAttributeType; in general it will be adirectoryString. AdirectoryStringis usually one ofPrintableString,TeletexStringorUniversalString.- Returns:
- a Principal whose name is the issuer distinguished name.
 
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getSubjectDNDeprecated, for removal: This API element is subject to removal in a future version.Gets thesubject(subject distinguished name) value from the certificate. The ASN.1 definition for this is:subject Name See getIssuerDNforNameand other relevant definitions.- Returns:
- a Principal whose name is the subject name.
- See Also:
 
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getNotBeforeDeprecated, for removal: This API element is subject to removal in a future version.Gets thenotBeforedate from the validity period of the certificate. The relevant ASN.1 definitions are:validity Validity Validity ::= SEQUENCE { notBefore CertificateValidityDate, notAfter CertificateValidityDate } CertificateValidityDate ::= CHOICE { utcTime UTCTime, generalTime GeneralizedTime }- Returns:
- the start date of the validity period.
- See Also:
 
- 
getNotAfterDeprecated, for removal: This API element is subject to removal in a future version.Gets thenotAfterdate from the validity period of the certificate. SeegetNotBeforefor relevant ASN.1 definitions.- Returns:
- the end date of the validity period.
- See Also:
 
- 
getSigAlgNameDeprecated, for removal: This API element is subject to removal in a future version.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: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 valueThe algorithm name is determined from the algorithmOID string.- Returns:
- the signature algorithm name.
 
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getSigAlgOIDDeprecated, for removal: This API element is subject to removal in a future version.Gets the signature algorithm OID string from the certificate. An OID is represented by a set of positive 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 the PKIX part I.See getSigAlgNamefor relevant ASN.1 definitions.- Returns:
- the signature algorithm OID string.
 
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getSigAlgParamspublic abstract byte[] getSigAlgParams()Deprecated, for removal: This API element is subject to removal in a future version.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.See getSigAlgNamefor relevant ASN.1 definitions.- Returns:
- the DER-encoded signature algorithm parameters, or null if no parameters are present.
 
 
- 
java.security.certinstead.