public abstract Class X509Certificate

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 }

Exceptions

CertificateExpiredException:

if the certificate has expired.

CertificateNotYetValidException:

if the certificate is not yet valid.

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.

Parameters

date:Date

the Date to check against to see if this certificate is valid at that date/time.

Exceptions

CertificateExpiredException:

if the certificate has expired with respect to the date supplied.

CertificateNotYetValidException:

if the certificate is not yet valid with respect to the date supplied.

See Also

checkValidity()

Gets the certificate constraints path length from the critical BasicConstraints extension, (OID = 2.5.29.19).

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 pathLenConstraint field (see below) is meaningful only if cA 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.

The ASN.1 definition for this is:

BasicConstraints ::= SEQUENCE {
    cA                  BOOLEAN DEFAULT FALSE,
    pathLenConstraint   INTEGER (0..MAX) OPTIONAL }

Returns:int

the value of pathLenConstraint 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 pathLenConstraint does not appear, Integer.MAX_VALUE is returned to indicate that there is no limit to the allowed length of the certification path.

Gets an unmodifiable list of Strings representing the OBJECT IDENTIFIERs of the ExtKeyUsageSyntax 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:

ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId

KeyPurposeId ::= OBJECT IDENTIFIER

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 abstract and it provides a default implementation. Subclasses should override this method with a correct implementation.

Returns:List<String>

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.

Exceptions

CertificateParsingException:

if the extension cannot be decoded

Since

1.4

Gets an immutable collection of issuer alternative names from the IssuerAltName extension, (OID = 2.5.29.18).

The ASN.1 definition of the IssuerAltName extension is:

IssuerAltName ::= GeneralNames

If this certificate does not contain an IssuerAltName extension, null is returned. Otherwise, a Collection is returned with an entry representing each GeneralName included in the extension. Each entry is a List whose first entry is an Integer (the name type, 0-8) and whose second entry is a String or a byte array (the name, in string or ASN.1 DER encoded form, respectively). More entries may exist depending on the name type. For more details about the formats used for each name type, see the getSubjectAlternativeNames method.

Note that the Collection returned may contain more than one name of the same type. Also, note that the returned Collection is immutable and any entries containing byte arrays are cloned to protect against subsequent modifications.

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 abstract and it provides a default implementation. Subclasses should override this method with a correct implementation.

Returns:Collection<List<?>>

an immutable Collection of issuer alternative names (or null)

Exceptions

CertificateParsingException:

if the extension cannot be decoded

Since

1.4

Gets the issuer (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 ::= ANY

Returns:Principal

a Principal whose name is the issuer distinguished name.

Annotations

@Deprecated

since:16

Gets the issuerUniqueID 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 5280 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.

The ASN.1 definition for this is:

issuerUniqueID  [1]  IMPLICIT UniqueIdentifier OPTIONAL

UniqueIdentifier  ::=  BIT STRING

Returns:boolean[]

the issuer unique identifier or null if it is not present in the certificate.

Returns the issuer (issuer distinguished name) value from the certificate as an X500Principal.

It is recommended that subclasses override this method.

Returns:X500Principal

an X500Principal representing the issuer distinguished name

Since

1.4

Gets a boolean array representing bits of the KeyUsage 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:

KeyUsage ::= BIT STRING {
    digitalSignature        (0),
    nonRepudiation          (1),
    keyEncipherment         (2),
    dataEncipherment        (3),
    keyAgreement            (4),
    keyCertSign             (5),
    cRLSign                 (6),
    encipherOnly            (7),
    decipherOnly            (8) }

Returns:boolean[]

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.

Gets the notAfter date from the validity period of the certificate. See getNotBefore for relevant ASN.1 definitions.

Returns:Date

the end date of the validity period.

See Also

checkValidity

Gets the notBefore date 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:Date

the start date of the validity period.

See Also

checkValidity

Gets the serialNumber 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:

serialNumber     CertificateSerialNumber

CertificateSerialNumber  ::=  INTEGER

Returns:BigInteger

the serial number.

Gets the signature algorithm name for the certificate signature algorithm. An example is the string "SHA256withRSA". 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:String

the signature algorithm name.

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 RFC 3279: Algorithms and Identifiers for the Internet X.509 Public Key Infrastructure Certificate and CRL Profile.

See getSigAlgName for relevant ASN.1 definitions.

Returns:String

the signature algorithm OID string.

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 AlgorithmParameters and instantiate with the name returned by getSigAlgName.

See getSigAlgName for relevant ASN.1 definitions.

Returns:byte[]

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

Gets the signature value (the raw signature bits) from the certificate. The ASN.1 definition for this is:

signature     BIT STRING

Returns:byte[]

the signature.

Gets an immutable collection of subject alternative names from the SubjectAltName extension, (OID = 2.5.29.17).

The ASN.1 definition of the SubjectAltName extension is:

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}

OtherName ::= SEQUENCE {
     type-id    OBJECT IDENTIFIER,
     value      [0] EXPLICIT ANY DEFINED BY type-id }

If this certificate does not contain a SubjectAltName extension, null is returned. Otherwise, a Collection is returned with an entry representing each GeneralName included in the extension. Each entry is a List whose first entry is an Integer (the name type, 0-8) and whose second entry is a String or a byte array (the name, in string or ASN.1 DER encoded form, respectively). More entries may exist depending on the name type.

RFC 822, DNS, and URI names are returned as Strings, using the well-established string formats for those types (subject to the restrictions included in RFC 5280). 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 Strings represented as a series of nonnegative integers separated by periods. Directory names (distinguished names) are returned in RFC 2253 string format. No standard string format is defined for X.400 names or EDI party names. They are returned as byte arrays containing the ASN.1 DER encoded form of the name. otherNames are also returned as byte arrays containing the ASN.1 DER encoded form of the name. A third entry may also be present in the list containing the type-id of the otherName in string form, and a fourth entry containing its value as either a string (if the value is a valid supported character string) or a byte array containing the ASN.1 DER encoded form of the value without the context-specific constructed tag with number 0.

Note that the Collection returned may contain more than one name of the same type. Also, note that the returned Collection is immutable and any entries containing byte arrays are cloned to protect against subsequent modifications.

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 abstract and it provides a default implementation. Subclasses should override this method with a correct implementation.

Returns:Collection<List<?>>

an immutable Collection of subject alternative names (or null)

Exceptions

CertificateParsingException:

if the extension cannot be decoded

Since

1.4

Gets the subject (subject distinguished name) value from the certificate. If the subject value is empty, then the getName() method of the returned Principal object returns an empty string ("").

The ASN.1 definition for this is:

subject    Name

See getIssuerDN for Name and other relevant definitions.

Returns:Principal

a Principal whose name is the subject name.

Annotations

@Deprecated

since:16

Gets the subjectUniqueID value from the certificate.

The ASN.1 definition for this is:

subjectUniqueID  [2]  IMPLICIT UniqueIdentifier OPTIONAL

UniqueIdentifier  ::=  BIT STRING

Returns:boolean[]

the subject unique identifier or null if it is not present in the certificate.

Returns the subject (subject distinguished name) value from the certificate as an X500Principal. If the subject value is empty, then the getName() method of the returned X500Principal object returns an empty string ("").

It is recommended that subclasses override this method.

Returns:X500Principal

an X500Principal representing the subject distinguished name

Since

1.4

Gets the DER-encoded certificate information, the tbsCertificate from this certificate. This can be used to verify the signature independently.

Returns:byte[]

the DER-encoded certificate information.

Exceptions

CertificateEncodingException:

if an encoding error occurs.

Gets the version (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:int

the version number, i.e. 1, 2 or 3.

Overrides java.security.cert.Certificate.verify.

Verifies that this certificate was signed using the private key that corresponds to the specified public key. This method uses the signature verification engine supplied by the specified provider. Note that the specified Provider object does not have to be registered in the provider list. This method was added to version 1.8 of the Java Platform Standard Edition. In order to maintain backwards compatibility with existing service providers, this method is not abstract and it provides a default implementation.

Parameters

key:PublicKey

the PublicKey used to carry out the verification.

sigProvider:Provider

the signature provider.

Exceptions

CertificateException:

on encoding errors.

NoSuchAlgorithmException:

on unsupported signature algorithms.

InvalidKeyException:

on incorrect key.

SignatureException:

on signature errors.

UnsupportedOperationException:

if the method is not supported

Since

1.8