- All Known Implementing Classes:
public interface DomainCombinerA
DomainCombinerprovides a means to dynamically update the ProtectionDomains associated with the current
DomainCombineris passed as a parameter to the appropriate constructor for
AccessControlContext. The newly constructed context is then passed to the
AccessController.doPrivileged(..., context)method to bind the provided context (and associated
DomainCombiner) with the current execution Thread. Subsequent calls to
DomainCombiner.combineto get invoked.
The combine method takes two arguments. The first argument represents an array of ProtectionDomains from the current execution Thread, since the most recent call to
AccessController.doPrivileged. If no call to doPrivileged was made, then the first argument will contain all the ProtectionDomains from the current execution Thread. The second argument represents an array of inherited ProtectionDomains, which may be
null. ProtectionDomains may be inherited from a parent Thread, or from a privileged context. If no call to doPrivileged was made, then the second argument will contain the ProtectionDomains inherited from the parent Thread. If one or more calls to doPrivileged were made, and the most recent call was to doPrivileged(action, context), then the second argument will contain the ProtectionDomains from the privileged context. If the most recent call was to doPrivileged(action), then there is no privileged context, and the second argument will be
combinemethod investigates the two input arrays of ProtectionDomains and returns a single array containing the updated ProtectionDomains. In the simplest case, the
combinemethod merges the two stacks into one. In more complex cases, the
combinemethod returns a modified stack of ProtectionDomains. The modification may have added new ProtectionDomains, removed certain ProtectionDomains, or simply updated existing ProtectionDomains. Re-ordering and other optimizations to the ProtectionDomains are also permitted. Typically the
combinemethod bases its updates on the information encapsulated in the
AccessController.getContextmethod receives the combined stack of ProtectionDomains back from the
DomainCombiner, it returns a new AccessControlContext that has both the combined ProtectionDomains as well as the
ProtectionDomain combine(ProtectionDomain currentDomains, ProtectionDomain assignedDomains)Modify or update the provided ProtectionDomains. ProtectionDomains may be added to or removed from the given ProtectionDomains. The ProtectionDomains may be re-ordered. Individual ProtectionDomains may be modified (with a new set of Permissions, for example).
currentDomains- the ProtectionDomains associated with the current execution Thread, up to the most recent privileged
ProtectionDomain. The ProtectionDomains are listed in order of execution, with the most recently executing
ProtectionDomainresiding at the beginning of the array. This parameter may be
nullif the current execution Thread has no associated ProtectionDomains.
assignedDomains- an array of inherited ProtectionDomains. ProtectionDomains may be inherited from a parent Thread, or from a privileged
AccessControlContext. This parameter may be
nullif there are no inherited ProtectionDomains.
- a new array consisting of the updated ProtectionDomains,