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package java.security.acl;

import java.util.Enumeration;
import java.security.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. 
Author:     Satish Dharmaraj
Since:1.1
Deprecated:This class is deprecated and subject to removal in a future version of Java SE. It has been replaced by java.security.Policy and related classes since 1.2.
/**
 * This interface is used to represent a group of principals. (A principal
 * represents an entity such as an individual user or a company). <p>
 *
 * 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 {@code addMember} method, passing it the
 * Principal or Group.
 *
 * @author      Satish Dharmaraj
 * @since 1.1
 *
 * @deprecated This class is deprecated and subject to removal in a future
 *     version of Java SE. It has been replaced by {@code java.security.Policy}
 *     and related classes since 1.2.
 */
@Deprecated(since="9", forRemoval=true)
public interface Group extends Principal {

    
Adds the specified member to the group.

Params:
  • user – the principal to add to this group.
Returns:true if the member was successfully added,
false if the principal was already a member.
/**
     * Adds the specified member to the group.
     *
     * @param user the principal to add to this group.
     *
     * @return true if the member was successfully added,
     * false if the principal was already a member.
     */
    public boolean addMember(Principal user);

    
Removes the specified member from the group.

Params:
  • user – the principal to remove from this group.
Returns:true if the principal was removed, or
false if the principal was not a member.
/**
     * Removes the specified member from the group.
     *
     * @param user the principal to remove from this group.
     *
     * @return true if the principal was removed, or
     * false if the principal was not a member.
     */
    public boolean removeMember(Principal user);

    
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.

Params:
  • member – the principal whose membership is to be checked.
Returns:true if the principal is a member of this group,
false otherwise.
/**
     * 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.
     *
     * @param member the principal whose membership is to be checked.
     *
     * @return true if the principal is a member of this group,
     * false otherwise.
     */
    public boolean isMember(Principal member);


    
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.
/**
     * 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).
     *
     * @return an enumeration of the group members.
     */
    public Enumeration<? extends Principal> members();

}