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

• All Superinterfaces:
  Principal

public interface Group
extends Principal
This interface is used to represent a group of principals. (A principal represents an entity such as an individual user or a company).
Note that Group extends Principal. Thus, either a Principal or a Group can be passed as an argument to methods containing a Principal parameter. For example, you can add either a Principal or a Group to a Group object by calling the object's addMember method, passing it the Principal or Group.

• • Method Summary

  All Methods Instance Methods Abstract Methods

  Modifier and Type	Method	Description
  boolean	addMember(Principal user)	Adds the specified member to the group.
  boolean	isMember(Principal member)	Returns true if the passed principal is a member of the group.
  Enumeration<? extends Principal>	members()	Returns an enumeration of the members in the group.
  boolean	removeMember(Principal user)	Removes the specified member from the group.

     * ### Methods inherited from interface java.security.[Principal](../../../java/security/Principal.html "interface in java.security")  
     `[equals](../../../java/security/Principal.html#equals-java.lang.Object-), [getName](../../../java/security/Principal.html#getName--), [hashCode](../../../java/security/Principal.html#hashCode--), [implies](../../../java/security/Principal.html#implies-javax.security.auth.Subject-), [toString](../../../java/security/Principal.html#toString--)`

• • Method Detail

     * #### addMember  
     boolean addMember([Principal](../../../java/security/Principal.html "interface in java.security") user)  
     Adds the specified member to the group.  
     Parameters:  
     `user` \- the principal to add to this group.  
     Returns:  
     true if the member was successfully added, false if the principal was already a member.  
     * #### removeMember  
     boolean removeMember([Principal](../../../java/security/Principal.html "interface in java.security") user)  
     Removes the specified member from the group.  
     Parameters:  
     `user` \- the principal to remove from this group.  
     Returns:  
     true if the principal was removed, or false if the principal was not a member.  
     * #### isMember  
     boolean isMember([Principal](../../../java/security/Principal.html "interface in java.security") member)  
     Returns true if the passed principal is a member of the group. This method does a recursive search, so if a principal belongs to a group which is a member of this group, true is returned.  
     Parameters:  
     `member` \- the principal whose membership is to be checked.  
     Returns:  
     true if the principal is a member of this group, false otherwise.  
     * #### members  
     [Enumeration](../../../java/util/Enumeration.html "interface in java.util")<? extends [Principal](../../../java/security/Principal.html "interface in java.security")> members()  
     Returns an enumeration of the members in the group. The returned objects can be instances of either Principal or Group (which is a subclass of Principal).  
     Returns:  
     an enumeration of the group members.

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