net.jini.core.constraint
Class ServerMinPrincipal

java.lang.Object
  net.jini.core.constraint.ServerMinPrincipal

All Implemented Interfaces:

Serializable, InvocationConstraint

public final class ServerMinPrincipal
extends Object
implements InvocationConstraint, Serializable

Represents a constraint on the server, such that if the server authenticates itself, then it must authenticate itself as at least all of the specified principals. The mechanisms and credentials used to authenticate the server as those principals are not specified by this constraint.

The use of an instance of this class does not imply directly a ServerAuthentication.YES constraint; that must be specified separately to ensure that the server actually authenticates itself. Because this constraint is conditional on server authentication, it does not conflict with ServerAuthentication.NO.

It is important to understand that specifying ServerAuthentication.YES as a requirement does not ensure that a server is to be trusted; it does ensure that the server authenticates itself as someone, but it does not ensure that the server authenticates itself as anyone in particular. Without knowing who the server authenticated itself as, there is no basis for actually trusting the server. The client generally needs to specify a ServerMinPrincipal requirement in addition, or else verify that the server has specified a satisfactory ServerMinPrincipal requirement for each of the methods that the client cares about.

Since:

2.0

Author:

Sun Microsystems, Inc.

See Also:

ServerAuthentication, AuthenticationPermission, Serialized Form

Constructor Summary

ServerMinPrincipal(Collection c)
Creates a constraint containing the specified principals, with duplicates removed.

ServerMinPrincipal(Principal p)
Creates a constraint containing the specified principal.

ServerMinPrincipal(Principal[] principals)
Creates a constraint containing the specified principals, with duplicates removed.

Method Summary

Set	elements() Returns an immutable set of all of the principals.
boolean	equals(Object obj) Two instances of this class are equal if they have the same principals (ignoring order).
int	hashCode() Returns a hash code value for this object.
String	toString() Returns a string representation of this object.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

ServerMinPrincipal

public ServerMinPrincipal(Principal p)

Creates a constraint containing the specified principal. This constructor is equivalent to calling a constructor with a single-element array containing the specified principal.

Parameters:

p - the principal

Throws:

NullPointerException - if the argument is null

ServerMinPrincipal

public ServerMinPrincipal(Principal[] principals)

Creates a constraint containing the specified principals, with duplicates removed. The argument passed to the constructor is neither modified nor retained; subsequent changes to that argument have no effect on the instance created.

Parameters:

principals - the principals

Throws:

NullPointerException - if the argument is null or any element is null

IllegalArgumentException - if the argument is empty

ServerMinPrincipal

public ServerMinPrincipal(Collection c)

Creates a constraint containing the specified principals, with duplicates removed. The argument passed to the constructor is neither modified nor retained; subsequent changes to that argument have no effect on the instance created.

Parameters:

c - the principals

Throws:

NullPointerException - if the argument is null or any element is null

IllegalArgumentException - if the argument is empty or the elements do not all implement the Principal interface

Method Detail

elements

public Set elements()

Returns an immutable set of all of the principals. Any attempt to modify the set results in an UnsupportedOperationException being thrown.

Returns:

an immutable set of all of the principals

hashCode

public int hashCode()

Returns a hash code value for this object.

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Two instances of this class are equal if they have the same principals (ignoring order).

Overrides:

equals in class Object

toString

public String toString()

Returns a string representation of this object.

Overrides:

toString in class Object