# Class PKIXRevocationChecker

java.lang.Object
java.security.cert.PKIXCertPathChecker
java.security.cert.PKIXRevocationChecker

All Implemented Interfaces:
  `Cloneable, CertPathChecker`

public abstract class PKIXRevocationChecker extends PKIXCertPathChecker
A `PKIXCertPathChecker` for checking the revocation status of certificates with the PKIX algorithm.

A `PKIXRevocationChecker` checks the revocation status of certificates with the Online Certificate Status Protocol (OCSP) or Certificate Revocation Lists (CRLs). OCSP is described in RFC 2560 and is a network protocol for determining the status of a certificate. A CRL is a time-stamped list identifying revoked certificates, and RFC 5280 describes an algorithm for determining the revocation status of certificates using CRLs.

Each `PKIXRevocationChecker` must be able to check the revocation status of certificates with OCSP and CRLs. By default, OCSP is the preferred mechanism for checking revocation status, with CRLs as the fallback mechanism. However, this preference can be switched to CRLs with the `PREFER_CRLS` option. In addition, the fallback mechanism can be disabled with the `NO_FALLBACK` option.

A `PKIXRevocationChecker` is obtained by calling the `getRevocationChecker` method of a PKIX `CertPathValidator`. Additional parameters and options specific to revocation can be set (by calling the `setOcspResponder` method for instance). The `PKIXRevocationChecker` is added to a `PKIXParameters` object using the `addCertPathChecker` or `setCertPathCheckers` method, and then the `PKIXParameters` is passed along with the `CertPath` to be validated to the `validate` method of a PKIX `CertPathValidator`. When supplying a revocation checker in this manner, it will be used to check revocation irrespective of the setting of the `RevocationEnabled` flag, and will override the default revocation checking mechanism of the PKIX service provider. Similarly, a `PKIXRevocationChecker` may be added to a `PKIXBuilderParameters` object for use with a PKIX `CertPathBuilder`.

Note that when a `PKIXRevocationChecker` is added to `PKIXParameters`, it clones the `PKIXRevocationChecker`; thus any subsequent modifications to the `PKIXRevocationChecker` have no effect.

Any parameter that is not set (or is set to `null`) will be set to the default value for that parameter.

Concurrent Access

Unless otherwise specified, the methods defined in this class are not thread-safe. Multiple threads that need to access a single object concurrently should synchronize amongst themselves and provide the necessary locking. Multiple threads each manipulating separate objects need not synchronize.

Since:
  1.8
External Specifications
  - RFC 2560: X.509 Internet Public Key Infrastructure Online Certificate Status Protocol - OCSP
  - RFC 5280: Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `static enum`
  `PKIXRevocationChecker.Option`
  Various revocation options that can be specified for the revocation checking mechanism.

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `PKIXRevocationChecker()`
  Default constructor.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `PKIXRevocationChecker`
  `clone()`
  Returns a clone of this object.
  `List<Extension>`
  `getOcspExtensions()`
  Gets the optional OCSP request extensions.
  `URI`
  `getOcspResponder()`
  Gets the URI that identifies the location of the OCSP responder.
  `X509Certificate`
  `getOcspResponderCert()`
  Gets the OCSP responder's certificate.
  `Map<X509Certificate, byte[]>`
  `getOcspResponses()`
  Gets the OCSP responses.
  `Set<PKIXRevocationChecker.Option>`
  `getOptions()`
  Gets the revocation options.
  `abstract List<CertPathValidatorException>`
  `getSoftFailExceptions()`
  Returns a list containing the exceptions that are ignored by the revocation checker when the `SOFT_FAIL` option is set.
  `void`
  `setOcspExtensions(List<Extension> extensions)`
  Sets the optional OCSP request extensions.
  `void`
  `setOcspResponder(URI uri)`
  Sets the URI that identifies the location of the OCSP responder.
  `void`
  `setOcspResponderCert(X509Certificate cert)`
  Sets the OCSP responder's certificate.
  `void`
  `setOcspResponses(Map<X509Certificate, byte[]> responses)`
  Sets the OCSP responses.
  `void`
  `setOptions(Set<PKIXRevocationChecker.Option> options)`
  Sets the revocation options.

  ### Methods declared in class PKIXCertPathChecker

  `check, check, getSupportedExtensions, init, isForwardCheckingSupported`

  ### Methods declared in class Object

  `equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Constructor Details

  - ### PKIXRevocationChecker

    protected PKIXRevocationChecker()
    Default constructor.

- ## Method Details

  - ### setOcspResponder

    public void setOcspResponder(URI uri)
    Sets the URI that identifies the location of the OCSP responder. This overrides the `ocsp.responderURL` security property and any responder specified in a certificate's Authority Information Access Extension, as defined in RFC 5280.
    Parameters:
      `uri` - the responder URI

  - ### getOcspResponder

    public URI getOcspResponder()
    Gets the URI that identifies the location of the OCSP responder. This overrides the `ocsp.responderURL` security property. If this parameter or the `ocsp.responderURL` property is not set, the location is determined from the certificate's Authority Information Access Extension, as defined in RFC 5280.
    Returns:
      the responder URI, or `null` if not set

  - ### setOcspResponderCert

    public void setOcspResponderCert(X509Certificate cert)
    Sets the OCSP responder's certificate. This overrides the `ocsp.responderCertSubjectName`, `ocsp.responderCertIssuerName`, and `ocsp.responderCertSerialNumber` security properties.
    Parameters:
      `cert` - the responder's certificate

  - ### getOcspResponderCert

    public X509Certificate getOcspResponderCert()
    Gets the OCSP responder's certificate. This overrides the `ocsp.responderCertSubjectName`, `ocsp.responderCertIssuerName`, and `ocsp.responderCertSerialNumber` security properties. If this parameter or the aforementioned properties are not set, then the responder's certificate is determined as specified in RFC 2560.
    Returns:
      the responder's certificate, or `null` if not set

  - ### setOcspExtensions

    public void setOcspExtensions(List<Extension> extensions)
    Sets the optional OCSP request extensions.
    Parameters:
      `extensions` - a list of extensions. The list is copied to protect against subsequent modification.

  - ### getOcspExtensions

    public List<Extension> getOcspExtensions()
    Gets the optional OCSP request extensions.
    Returns:
      an unmodifiable list of extensions. The list is empty if no extensions have been specified.

  - ### setOcspResponses

    public void setOcspResponses(Map<X509Certificate, byte[]> responses)
    Sets the OCSP responses. These responses are used to determine the revocation status of the specified certificates when OCSP is used.
    Parameters:
      `responses` - a map of OCSP responses. Each key is an `X509Certificate` that maps to the corresponding DER-encoded OCSP response for that certificate. A deep copy of the map is performed to protect against subsequent modification.

  - ### getOcspResponses

    public Map<X509Certificate, byte[]> getOcspResponses()
    Gets the OCSP responses. These responses are used to determine the revocation status of the specified certificates when OCSP is used.
    Returns:
      a map of OCSP responses. Each key is an `X509Certificate` that maps to the corresponding DER-encoded OCSP response for that certificate. A deep copy of the map is returned to protect against subsequent modification. Returns an empty map if no responses have been specified.

  - ### setOptions

    public void setOptions(Set<PKIXRevocationChecker.Option> options)
    Sets the revocation options.
    Parameters:
      `options` - a set of revocation options. The set is copied to protect against subsequent modification.

  - ### getOptions

    public Set<PKIXRevocationChecker.Option> getOptions()
    Gets the revocation options.
    Returns:
      an unmodifiable set of revocation options. The set is empty if no options have been specified.

  - ### getSoftFailExceptions

    public abstract List<CertPathValidatorException> getSoftFailExceptions()
    Returns a list containing the exceptions that are ignored by the revocation checker when the `SOFT_FAIL` option is set. The list is cleared each time `init` is called. The list is ordered in ascending order according to the certificate index returned by `getIndex` method of each entry.

    An implementation of `PKIXRevocationChecker` is responsible for adding the ignored exceptions to the list.

    Returns:
      an unmodifiable list containing the ignored exceptions. The list is empty if no exceptions have been ignored.

  - ### clone

    public PKIXRevocationChecker clone()
    Description copied from class: `PKIXCertPathChecker`
    Returns a clone of this object. Calls the `Object.clone()` method. All subclasses which maintain state must support and override this method, if necessary.
    Overrides:
      `clone` in class `PKIXCertPathChecker`
    Returns:
      a copy of this `PKIXCertPathChecker`
    See Also:
      - `Cloneable`