# Class CertStore

java.lang.Object
java.security.cert.CertStore

public class CertStore extends Object
A class for retrieving `Certificate`s and `CRL`s from a repository.

This class uses a provider-based architecture. To create a `CertStore`, call one of the static `getInstance` methods, passing in the type of `CertStore` desired, any applicable initialization parameters and optionally the name of the provider desired.

Once the `CertStore` has been created, it can be used to retrieve `Certificate`s and `CRL`s by calling its `getCertificates` and `getCRLs` methods.

Unlike a `KeyStore`, which provides access to a cache of private keys and trusted certificates, a `CertStore` is designed to provide access to a potentially vast repository of untrusted certificates and CRLs. For example, an LDAP implementation of `CertStore` provides access to certificates and CRLs stored in one or more directories using the LDAP protocol and the schema as defined in the RFC service attribute.

Every implementation of the Java platform is required to support the following standard `CertStore` type:

- `Collection`

This type is described in the CertStore section of the Java Security Standard Algorithm Names Specification. Consult the release documentation for your implementation to see if any other types are supported.

Concurrent Access

All public methods of `CertStore` objects must be thread-safe. That is, multiple threads may concurrently invoke these methods on a single `CertStore` object (or more than one) with no ill effects. This allows a `CertPathBuilder` to search for a CRL while simultaneously searching for further certificates, for instance.

The static methods of this class are also guaranteed to be thread-safe. Multiple threads may concurrently invoke the static methods defined in this class with no ill effects.

Since:
  1.4
External Specifications
  - Java Security Standard Algorithm Names

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `CertStore(CertStoreSpi storeSpi, Provider provider, String type, CertStoreParameters params)`
  Creates a `CertStore` object of the given type, and encapsulates the given provider implementation (SPI object) in it.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `final Collection<? extends Certificate>`
  `getCertificates(CertSelector selector)`
  Returns a `Collection` of `Certificate`s that match the specified selector.
  `final CertStoreParameters`
  `getCertStoreParameters()`
  Returns the parameters used to initialize this `CertStore`.
  `final Collection<? extends CRL>`
  `getCRLs(CRLSelector selector)`
  Returns a `Collection` of `CRL`s that match the specified selector.
  `static final String`
  `getDefaultType()`
  Returns the default `CertStore` type as specified by the `certstore.type` security property, or the string "LDAP" if no such property exists.
  `static CertStore`
  `getInstance(String type, CertStoreParameters params)`
  Returns a `CertStore` object that implements the specified `CertStore` type and is initialized with the specified parameters.
  `static CertStore`
  `getInstance(String type, CertStoreParameters params, String provider)`
  Returns a `CertStore` object that implements the specified `CertStore` type.
  `static CertStore`
  `getInstance(String type, CertStoreParameters params, Provider provider)`
  Returns a `CertStore` object that implements the specified `CertStore` type.
  `final Provider`
  `getProvider()`
  Returns the provider of this `CertStore`.
  `final String`
  `getType()`
  Returns the type of this `CertStore`.

  ### Methods declared in class Object

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

- ## Constructor Details

  - ### CertStore

    protected CertStore(CertStoreSpi storeSpi, Provider provider, String type, CertStoreParameters params)
    Creates a `CertStore` object of the given type, and encapsulates the given provider implementation (SPI object) in it.
    Parameters:
      `storeSpi` - the provider implementation
      `provider` - the provider
      `type` - the type
      `params` - the initialization parameters (may be `null`)

- ## Method Details

  - ### getCertificates

    public final Collection<? extends Certificate> getCertificates(CertSelector selector) throws CertStoreException
    Returns a `Collection` of `Certificate`s that match the specified selector. If no `Certificate`s match the selector, an empty `Collection` will be returned.

    For some `CertStore` types, the resulting `Collection` may not contain all of the `Certificate`s that match the selector. For instance, an LDAP `CertStore` may not search all entries in the directory. Instead, it may just search entries that are likely to contain the `Certificate`s it is looking for.

    Some `CertStore` implementations (especially LDAP `CertStore`s) may throw a `CertStoreException` unless a non-null `CertSelector` is provided that includes specific criteria that can be used to find the certificates. Issuer and/or subject names are especially useful criteria.

    Parameters:
      `selector` - A `CertSelector` used to select which `Certificate`s should be returned. Specify `null` to return all `Certificate`s (if supported).
    Returns:
      A `Collection` of `Certificate`s that match the specified selector (never `null`)
    Throws:
      `CertStoreException` - if an exception occurs

  - ### getCRLs

    public final Collection<? extends CRL> getCRLs(CRLSelector selector) throws CertStoreException
    Returns a `Collection` of `CRL`s that match the specified selector. If no `CRL`s match the selector, an empty `Collection` will be returned.

    For some `CertStore` types, the resulting `Collection` may not contain all of the `CRL`s that match the selector. For instance, an LDAP `CertStore` may not search all entries in the directory. Instead, it may just search entries that are likely to contain the `CRL`s it is looking for.

    Some `CertStore` implementations (especially LDAP `CertStore`s) may throw a `CertStoreException` unless a non-null `CRLSelector` is provided that includes specific criteria that can be used to find the CRLs. Issuer names and/or the certificate to be checked are especially useful.

    Parameters:
      `selector` - A `CRLSelector` used to select which `CRL`s should be returned. Specify `null` to return all `CRL`s (if supported).
    Returns:
      A `Collection` of `CRL`s that match the specified selector (never `null`)
    Throws:
      `CertStoreException` - if an exception occurs

  - ### getInstance

    public static CertStore getInstance(String type, CertStoreParameters params) throws InvalidAlgorithmParameterException, NoSuchAlgorithmException
    Returns a `CertStore` object that implements the specified `CertStore` type and is initialized with the specified parameters.

    This method traverses the list of registered security Providers, starting with the most preferred Provider. A new CertStore object encapsulating the CertStoreSpi implementation from the first Provider that supports the specified type is returned.

    Note that the list of registered providers may be retrieved via the `Security.getProviders()` method.

    The `CertStore` that is returned is initialized with the specified `CertStoreParameters`. The type of parameters needed may vary between different types of `CertStore`s. Note that the specified `CertStoreParameters` object is cloned.

    Implementation Note:
      The JDK Reference Implementation additionally uses the `jdk.security.provider.preferred` `Security` property to determine the preferred provider order for the specified algorithm. This may be different from the order of providers returned by `Security.getProviders()`.
    Parameters:
      `type` - the name of the requested `CertStore` type. See the CertStore section in the Java Security Standard Algorithm Names Specification for information about standard types.
      `params` - the initialization parameters (may be `null`).
    Returns:
      a `CertStore` object that implements the specified `CertStore` type
    Throws:
      `InvalidAlgorithmParameterException` - if the specified initialization parameters are inappropriate for this `CertStore`
      `NoSuchAlgorithmException` - if no `Provider` supports a `CertStoreSpi` implementation for the specified type
      `NullPointerException` - if `type` is `null`
    External Specifications
      - Java Security Standard Algorithm Names
    See Also:
      - `Provider`

  - ### getInstance

    public static CertStore getInstance(String type, CertStoreParameters params, String provider) throws InvalidAlgorithmParameterException, NoSuchAlgorithmException, NoSuchProviderException
    Returns a `CertStore` object that implements the specified `CertStore` type.

    A new CertStore object encapsulating the CertStoreSpi implementation from the specified provider is returned. The specified provider must be registered in the security provider list.

    Note that the list of registered providers may be retrieved via the `Security.getProviders()` method.

    The `CertStore` that is returned is initialized with the specified `CertStoreParameters`. The type of parameters needed may vary between different types of `CertStore`s. Note that the specified `CertStoreParameters` object is cloned.

    Parameters:
      `type` - the requested `CertStore` type. See the CertStore section in the Java Security Standard Algorithm Names Specification for information about standard types.
      `params` - the initialization parameters (may be `null`).
      `provider` - the name of the provider.
    Returns:
      a `CertStore` object that implements the specified type
    Throws:
      `IllegalArgumentException` - if the `provider` is `null` or empty
      `InvalidAlgorithmParameterException` - if the specified initialization parameters are inappropriate for this `CertStore`
      `NoSuchAlgorithmException` - if a `CertStoreSpi` implementation for the specified type is not available from the specified provider
      `NoSuchProviderException` - if the specified provider is not registered in the security provider list
      `NullPointerException` - if `type` is `null`
    External Specifications
      - Java Security Standard Algorithm Names
    See Also:
      - `Provider`

  - ### getInstance

    public static CertStore getInstance(String type, CertStoreParameters params, Provider provider) throws NoSuchAlgorithmException, InvalidAlgorithmParameterException
    Returns a `CertStore` object that implements the specified `CertStore` type.

    A new CertStore object encapsulating the CertStoreSpi implementation from the specified Provider object is returned. Note that the specified Provider object does not have to be registered in the provider list.

    The `CertStore` that is returned is initialized with the specified `CertStoreParameters`. The type of parameters needed may vary between different types of `CertStore`s. Note that the specified `CertStoreParameters` object is cloned.

    Parameters:
      `type` - the requested `CertStore` type. See the CertStore section in the Java Security Standard Algorithm Names Specification for information about standard types.
      `params` - the initialization parameters (may be `null`).
      `provider` - the provider.
    Returns:
      a `CertStore` object that implements the specified type
    Throws:
      `IllegalArgumentException` - if the `provider` is null
      `InvalidAlgorithmParameterException` - if the specified initialization parameters are inappropriate for this `CertStore`
      `NoSuchAlgorithmException` - if a `CertStoreSpi` implementation for the specified type is not available from the specified Provider object
      `NullPointerException` - if `type` is `null`
    External Specifications
      - Java Security Standard Algorithm Names
    See Also:
      - `Provider`

  - ### getCertStoreParameters

    public final CertStoreParameters getCertStoreParameters()
    Returns the parameters used to initialize this `CertStore`. Note that the `CertStoreParameters` object is cloned before it is returned.
    Returns:
      the parameters used to initialize this `CertStore` (may be `null`)

  - ### getType

    public final String getType()
    Returns the type of this `CertStore`.
    Returns:
      the type of this `CertStore`

  - ### getProvider

    public final Provider getProvider()
    Returns the provider of this `CertStore`.
    Returns:
      the provider of this `CertStore`

  - ### getDefaultType

    public static final String getDefaultType()
    Returns the default `CertStore` type as specified by the `certstore.type` security property, or the string "LDAP" if no such property exists.

    The default `CertStore` type can be used by applications that do not want to use a hard-coded type when calling one of the `getInstance` methods, and want to provide a default `CertStore` type in case a user does not specify its own.

    The default `CertStore` type can be changed by setting the value of the `certstore.type` security property to the desired type.

    Returns:
      the default `CertStore` type as specified by the `certstore.type` security property, or the string "LDAP" if no such property exists.
    See Also:
      - security properties