java.lang.Object java.security.cert.CertificateFactory
This class defines the functionality of a certificate factory, which is used to generate certificate, certification path (CertPath) and certificate revocation list (CRL) objects from their encodings.
For encodings consisting of multiple certificates, use generateCertificates when you want to parse a collection of possibly unrelated certificates. Otherwise, use generateCertPath when you want to generate a CertPath (a certificate chain) and subsequently validate it with a CertPathValidator.
A certificate factory for X.509 must return certificates that are an instance of java.security.cert.X509Certificate, and CRLs that are an instance of java.security.cert.X509CRL.
The following example reads a file with Base64 encoded certificates, which are each bounded at the beginning by -----BEGIN CERTIFICATE-----, and bounded at the end by -----END CERTIFICATE-----. We convert the FileInputStream (which does not support mark and reset) to a BufferedInputStream (which supports those methods), so that each call to generateCertificate consumes only one certificate, and the read position of the input stream is positioned to the next certificate in the file:
FileInputStream fis = new FileInputStream(filename); BufferedInputStream bis = new BufferedInputStream(fis); CertificateFactory cf = CertificateFactory.getInstance("X.509"); while (bis.available() > 0) { Certificate cert = cf.generateCertificate(bis); System.out.println(cert.toString()); }
The following example parses a PKCS#7-formatted certificate reply stored in a file and extracts all the certificates from it:
FileInputStream fis = new FileInputStream(filename); CertificateFactory cf = CertificateFactory.getInstance("X.509"); Collection c = cf.generateCertificates(fis); Iterator i = c.iterator(); while (i.hasNext()) { Certificate cert = (Certificate)i.next(); System.out.println(cert); }
Constructor Summary | |
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protected |
CertificateFactory
(
CertificateFactorySpi
certFacSpi,
Provider
provider,
String
type) Creates a CertificateFactory object of the given type, and encapsulates the given provider implementation (SPI object) in it. |
Method Summary | |
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Certificate |
generateCertificate
(
InputStream
inStream) Generates a certificate object and initializes it with the data read from the input stream inStream. |
Collection <? extends Certificate |
generateCertificates
(
InputStream
Returns a (possibly empty) collection view of the certificates read from the given input stream inStream. |
CertPath |
generateCertPath
(
InputStream
inStream) Generates a CertPath object and initializes it with the data read from the InputStream inStream. |
CertPath |
generateCertPath
(
InputStream
inStream,
String
encoding) Generates a CertPath object and initializes it with the data read from the InputStream inStream. |
CertPath |
generateCertPath
(
List
certificates) Generates a CertPath object and initializes it with a List of Certificates. |
CRL |
generateCRL
(
InputStream
inStream) Generates a certificate revocation list (CRL) object and initializes it with the data read from the input stream inStream. |
Collection <? extends CRL |
generateCRLs
(
InputStream
Returns a (possibly empty) collection view of the CRLs read from the given input stream inStream. |
Iterator < String |
getCertPathEncodings
() Returns an iteration of the CertPath encodings supported by this certificate factory, with the default encoding first. |
static CertificateFactory |
getInstance
(
String
type) Generates a certificate factory object that implements the specified certificate type. |
static CertificateFactory |
getInstance
(
String
type,
Provider
provider) Generates a certificate factory object for the specified certificate type from the specified provider. |
static CertificateFactory |
getInstance
(
String
type,
String
provider) Generates a certificate factory object for the specified certificate type from the specified provider. |
Provider |
getProvider
() Returns the provider of this certificate factory. |
String |
getType
() Returns the name of the certificate type associated with this certificate factory. |
Methods inherited from class java.lang. Object |
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clone , equals , finalize , getClass , hashCode , notify , notifyAll , toString , wait , wait , wait |
Constructor Detail |
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protected CertificateFactory(CertificateFactorySpi certFacSpi, Provider provider, String type)
Method Detail |
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public static final CertificateFactory getInstance(String type) throws CertificateException
public static final CertificateFactory getInstance(String type, String provider) throws CertificateException, NoSuchProviderException
public static final CertificateFactory getInstance(String type, Provider provider) throws CertificateException
public final Provider getProvider()
public final String getType()
public final Certificate generateCertificate(InputStream inStream) throws CertificateException
In order to take advantage of the specialized certificate format supported by this certificate factory, the returned certificate object can be typecast to the corresponding certificate class. For example, if this certificate factory implements X.509 certificates, the returned certificate object can be typecast to the X509Certificate class.
In the case of a certificate factory for X.509 certificates, the certificate provided in inStream must be DER-encoded and may be supplied in binary or printable (Base64) encoding. If the certificate is provided in Base64 encoding, it must be bounded at the beginning by -----BEGIN CERTIFICATE-----, and must be bounded at the end by -----END CERTIFICATE-----.
Note that if the given input stream does not support mark and reset , this method will consume the entire input stream. Otherwise, each call to this method consumes one certificate and the read position of the input stream is positioned to the next available byte after the inherent end-of-certificate marker. If the data in the input stream does not contain an inherent end-of-certificate marker (other than EOF) and there is trailing data after the certificate is parsed, a CertificateException is thrown.
public final Iterator< String> getCertPathEncodings()
Attempts to modify the returned Iterator via its remove method result in an UnsupportedOperationException.
public final CertPath generateCertPath(InputStream inStream) throws CertificateException
public final CertPath generateCertPath(InputStream inStream, String encoding) throws CertificateException
public final CertPath generateCertPath(List certificates) throws CertificateException
The certificates supplied must be of a type supported by the CertificateFactory. They will be copied out of the supplied List object.
public final Collection<? extends Certificate> generateCertificates(InputStream inStream) throws CertificateException
In order to take advantage of the specialized certificate format supported by this certificate factory, each element in the returned collection view can be typecast to the corresponding certificate class. For example, if this certificate factory implements X.509 certificates, the elements in the returned collection can be typecast to the X509Certificate class.
In the case of a certificate factory for X.509 certificates, inStream may contain a sequence of DER-encoded certificates in the formats described for generateCertificate . In addition, inStream may contain a PKCS#7 certificate chain. This is a PKCS#7 SignedData object, with the only significant field being certificates . In particular, the signature and the contents are ignored. This format allows multiple certificates to be downloaded at once. If no certificates are present, an empty collection is returned.
Note that if the given input stream does not support mark and reset , this method will consume the entire input stream.
public final CRL generateCRL(InputStream inStream) throws CRLException
In order to take advantage of the specialized CRL format supported by this certificate factory, the returned CRL object can be typecast to the corresponding CRL class. For example, if this certificate factory implements X.509 CRLs, the returned CRL object can be typecast to the X509CRL class.
Note that if the given input stream does not support mark and reset , this method will consume the entire input stream. Otherwise, each call to this method consumes one CRL and the read position of the input stream is positioned to the next available byte after the the inherent end-of-CRL marker. If the data in the input stream does not contain an inherent end-of-CRL marker (other than EOF) and there is trailing data after the CRL is parsed, a CRLException is thrown.
public final Collection<? extends CRL> generateCRLs(InputStream inStream) throws CRLException
In order to take advantage of the specialized CRL format supported by this certificate factory, each element in the returned collection view can be typecast to the corresponding CRL class. For example, if this certificate factory implements X.509 CRLs, the elements in the returned collection can be typecast to the X509CRL class.
In the case of a certificate factory for X.509 CRLs, inStream may contain a sequence of DER-encoded CRLs. In addition, inStream may contain a PKCS#7 CRL set. This is a PKCS#7 SignedData object, with the only significant field being crls . In particular, the signature and the contents are ignored. This format allows multiple CRLs to be downloaded at once. If no CRLs are present, an empty collection is returned.
Note that if the given input stream does not support mark and reset , this method will consume the entire input stream.