sun.security.mule.jgss
Class ProviderList

java.lang.Object
  sun.security.mule.jgss.ProviderList

public final class ProviderList
extends Object

This class stores the list of providers that this GSS-Implementation is configured to use. The GSSManagerImpl class queries this class whenever it needs a mechanism's factory.

This class stores an ordered list of pairs of the form . When it attempts to instantiate a mechanism defined by oid o, it steps through the list looking for an entry with oid=o, or with oid=null. (An entry with oid=null matches all mechanisms.) When it finds such an entry, the corresponding provider is approached for the mechanism's factory class. At instantiation time this list in initialized to contain those system wide providers that contain a property of the form "GssApiMechanism.x.y.z..." where "x.y.z..." is a numeric object identifier with numbers x, y, z, etc. Such a property is defined to map to that provider's implementation of the MechanismFactory interface for the mechanism x.y.z... As and when a MechanismFactory is instantiated, it is cached for future use.

An application can cause more providers to be added by means of the addProviderAtFront and addProviderAtEnd methods on GSSManager which get delegated to this class. The addProviderAtFront method can also cause a change in the ordering of the providers without adding any new providers, by causing a provider to move up in a list. The method addProviderAtEnd can only add providers at the end of the list if they are not already in the list. The rationale is that an application will call addProviderAtFront when it wants a provider to be used in preference over the default ones. And it will call addProviderAtEnd when it wants a provider to be used in case the system ones don't suffice.

If a mechanism's factory is being obtained from a provider as a result of encountering a entryof the form where oid is non-null, then the assumption is that the application added this entry and it wants this mechanism to be obtained from this provider. Thus is the provider does not actually contain the requested mechanism, an exception will be thrown. However, if the entry were of the form , then it is viewed more liberally and is simply skipped over if the provider does not claim to support the requested mechanism.

Field Summary

static Oid

DEFAULT_MECH_OID

Constructor Summary

ProviderList(int caller, boolean useNative, Config kerberosConfig)

Method Summary

void	addProviderAtEnd(Provider p, Oid mechOid)
void	addProviderAtFront(Provider p, Oid mechOid)
MechanismFactory	getMechFactory(Oid mechOid)
MechanismFactory	getMechFactory(Oid mechOid, Provider p) Obtains a MechanismFactory for a given mechanism.
Oid[]	getMechs()

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_MECH_OID

public static final Oid DEFAULT_MECH_OID

Constructor Detail

ProviderList

public ProviderList(int caller,
                    boolean useNative,
                    Config kerberosConfig)

Method Detail

getMechFactory

public MechanismFactory getMechFactory(Oid mechOid)
                                throws GSSException

Throws:

GSSException

getMechFactory

public MechanismFactory getMechFactory(Oid mechOid,
                                       Provider p)
                                throws GSSException

Obtains a MechanismFactory for a given mechanism. If the specified provider is not null, then the impl from the provider is used. Otherwise, the most preferred impl based on the configured preferences is used.

Parameters:

mechOid - the oid of the desired mechanism

Returns:

a MechanismFactory for the desired mechanism.

Throws:

GSSException - when the specified provider does not support the desired mechanism, or when no provider supports the desired mechanism.

getMechs

public Oid[] getMechs()

addProviderAtFront

public void addProviderAtFront(Provider p,
                               Oid mechOid)
                        throws GSSException

Throws:

GSSException

addProviderAtEnd

public void addProviderAtEnd(Provider p,
                             Oid mechOid)
                      throws GSSException

Throws:

GSSException