Class UserPrincipalLookupService
- java.lang.Object
-
- java.nio.file.attribute.UserPrincipalLookupService
public abstract class UserPrincipalLookupService extends Object
An object to lookup user and group principals by name. A UserPrincipal
represents an identity that may be used to determine access rights to objects in a file system. A GroupPrincipal
represents a group identity. A UserPrincipalLookupService
defines methods to lookup identities by name or group name (which are typically user or account names). Whether names and group names are case sensitive or not depends on the implementation. The exact definition of a group is implementation specific but typically a group represents an identity created for administrative purposes so as to determine the access rights for the members of the group. In particular it is implementation specific if the namespace for names and groups is the same or is distinct. To ensure consistent and correct behavior across platforms it is recommended that this API be used as if the namespaces are distinct. In other words, the lookupPrincipalByName
should be used to lookup users, and lookupPrincipalByGroupName
should be used to lookup groups.
- Since:
- 1.7
- See Also:
FileSystem.getUserPrincipalLookupService()
Constructor Summary
Modifier | Constructor | Description |
---|---|---|
protected | UserPrincipalLookupService() | Initializes a new instance of this class. |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
abstract GroupPrincipal | lookupPrincipalByGroupName(String group) | Lookup a group principal by group name. |
abstract UserPrincipal | lookupPrincipalByName(String name) | Lookup a user principal by name. |
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Constructor Detail
UserPrincipalLookupService
protected UserPrincipalLookupService()
Initializes a new instance of this class.
Method Detail
lookupPrincipalByName
public abstract UserPrincipal lookupPrincipalByName(String name) throws IOException
Lookup a user principal by name.
- Parameters:
-
name
- the string representation of the user principal to lookup - Returns:
- a user principal
- Throws:
-
UserPrincipalNotFoundException
- the principal does not exist -
IOException
- if an I/O error occurs -
SecurityException
- In the case of the default provider, and a security manager is installed, it checksRuntimePermission
("lookupUserInformation")
lookupPrincipalByGroupName
public abstract GroupPrincipal lookupPrincipalByGroupName(String group) throws IOException
Lookup a group principal by group name.
Where an implementation does not support any notion of group then this method always throws UserPrincipalNotFoundException
. Where the namespace for user accounts and groups is the same, then this method is identical to invoking lookupPrincipalByName
.
- Parameters:
-
group
- the string representation of the group to lookup - Returns:
- a group principal
- Throws:
-
UserPrincipalNotFoundException
- the principal does not exist or is not a group -
IOException
- if an I/O error occurs -
SecurityException
- In the case of the default provider, and a security manager is installed, it checksRuntimePermission
("lookupUserInformation")