UserPrincipalLookupService (Java Platform SE 8 ) (original) (raw)

• 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

  Constructors

  Modifier	Constructor	Description
  protected	UserPrincipalLookupService()	Initializes a new instance of this class.

  • Method Summary

  All Methods Instance Methods Abstract Methods

  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 inherited from class java.lang.[Object](../../../../java/lang/Object.html "class in java.lang")  
     `[clone](../../../../java/lang/Object.html#clone--), [equals](../../../../java/lang/Object.html#equals-java.lang.Object-), [finalize](../../../../java/lang/Object.html#finalize--), [getClass](../../../../java/lang/Object.html#getClass--), [hashCode](../../../../java/lang/Object.html#hashCode--), [notify](../../../../java/lang/Object.html#notify--), [notifyAll](../../../../java/lang/Object.html#notifyAll--), [toString](../../../../java/lang/Object.html#toString--), [wait](../../../../java/lang/Object.html#wait--), [wait](../../../../java/lang/Object.html#wait-long-), [wait](../../../../java/lang/Object.html#wait-long-int-)`

• • Constructor Detail

     * #### UserPrincipalLookupService  
     protected UserPrincipalLookupService()  
     Initializes a new instance of this class.  

  • Method Detail

    * #### lookupPrincipalByName  
    public abstract [UserPrincipal](../../../../java/nio/file/attribute/UserPrincipal.html "interface in java.nio.file.attribute") lookupPrincipalByName([String](../../../../java/lang/String.html "class in java.lang") name)  
                                                 throws [IOException](../../../../java/io/IOException.html "class in java.io")  
    Lookup a user principal by name.  
    Parameters:  
    `name` \- the string representation of the user principal to lookup  
    Returns:  
    a user principal  
    Throws:  
    `[UserPrincipalNotFoundException](../../../../java/nio/file/attribute/UserPrincipalNotFoundException.html "class in java.nio.file.attribute")` \- the principal does not exist  
    `[IOException](../../../../java/io/IOException.html "class in java.io")` \- if an I/O error occurs  
    `[SecurityException](../../../../java/lang/SecurityException.html "class in java.lang")` \- In the case of the default provider, and a security manager is installed, it checks [RuntimePermission](../../../../java/lang/RuntimePermission.html "class in java.lang")("lookupUserInformation")  
    * #### lookupPrincipalByGroupName  
    public abstract [GroupPrincipal](../../../../java/nio/file/attribute/GroupPrincipal.html "interface in java.nio.file.attribute") lookupPrincipalByGroupName([String](../../../../java/lang/String.html "class in java.lang") group)  
                                                       throws [IOException](../../../../java/io/IOException.html "class in java.io")  
    Lookup a group principal by group name.  
     Where an implementation does not support any notion of group then this method always throws [UserPrincipalNotFoundException](../../../../java/nio/file/attribute/UserPrincipalNotFoundException.html "class in java.nio.file.attribute"). Where the namespace for user accounts and groups is the same, then this method is identical to invoking [lookupPrincipalByName](../../../../java/nio/file/attribute/UserPrincipalLookupService.html#lookupPrincipalByName-java.lang.String-).  
    Parameters:  
    `group` \- the string representation of the group to lookup  
    Returns:  
    a group principal  
    Throws:  
    `[UserPrincipalNotFoundException](../../../../java/nio/file/attribute/UserPrincipalNotFoundException.html "class in java.nio.file.attribute")` \- the principal does not exist or is not a group  
    `[IOException](../../../../java/io/IOException.html "class in java.io")` \- if an I/O error occurs  
    `[SecurityException](../../../../java/lang/SecurityException.html "class in java.lang")` \- In the case of the default provider, and a security manager is installed, it checks [RuntimePermission](../../../../java/lang/RuntimePermission.html "class in java.lang")("lookupUserInformation")

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