spki
Class Empowerment

java.lang.Object
  |
  +--spki.BaseObj
        |
        +--spki.Empowerment

public class Empowerment

extends BaseObj

SPKI Empowerment class.

Format definitions:

 <redelegate>:: "delegatable" ;
 <transfer>:: "transferable" ;
 <propagate>:: <redelegate> | <transfer> ;
 <grant>:: "(" "grant" <propagate>? ")" ;
 <delegate>:: "(" "delegate" <redelegate>? ")" ;
 <emp-value>:: <grant> | <delegate> ;
 <empower>:: "(" "empower" <emp-value> ")" ;
 

Version:

$Id: Empowerment.java,v 1.10 2002/07/05 09:33:12 tep Exp $

Author:

Tep Narula <tep@win.trlabs.ca>

Field Summary

private static String	__ME This class's full name.
static int	DELEGATE Delegation (2).
static int	DELEGATEABLE Redelegation allowed (1).
static int	GRANT Granting (1).
private static int	MAX_EMPOWERMENT_VALUE
private static int	MAX_PROPAGATION_VALUE
private static int	MIN_EMPOWERMENT_VALUE
private static int	MIN_PROPAGATION_VALUE
static int	NO_PROPAGATION No propagation allowed (0).
static int	NOT_EMPOWERED Initial empowerment type (0).
private int	propagate the propgation-control type.
static String[]	PROPAGATE_SEXP_NAMES The propagate-control S-Expression values, used by toSExpression() and other methods.
static String	SEXP_NAME This class S-Expression type name, used by toSExpression() and other methods.
static int	TRANSFER Transfer (3).
static int	TRANSFERABLE Transfer allowed (2).
private int	type the empowerment type.
static String[]	TYPE_SEXP_NAMES The empowerment-type S-Expression values, used by toSExpression() and other methods.

Fields inherited from class spki.BaseObj

__ME, cache_sexp, cached_sexp, DEFAULT_HASH_ALG, locked, SEXP_NAME

Constructor Summary

protected	Empowerment() Don't use me!
	Empowerment(int type, int propagate) Create an immutable Empowerment object from the given empowerment type and, optionally, the propagation-control type.
	Empowerment(SExpression sexp) Create an immutable Empowerment object from an S-Expression.

Method Summary

int	getEmpowermentType() Get the empowerment type.
int	getPropagationType() Get the propgation-control type.
SExpression	toSExpression() Build an SExpression representing this object.

Methods inherited from class spki.BaseObj

disableSExpressionCaching, enableSExpressionCaching, extractHashAlgId, getCachedSExpression, isLocked, isSListOfType, lock, providerToSPKI, setCachedSExpression, spkiToProvider, toString

Methods inherited from class java.lang.Object

, clone, equals, finalize, getClass, hashCode, notify, notifyAll, registerNatives, wait, wait, wait

Field Detail

__ME

private static final String __ME

This class's full name.

SEXP_NAME

public static final String SEXP_NAME

This class S-Expression type name, used by toSExpression() and other methods.

See Also:

toSExpression()

TYPE_SEXP_NAMES

public static final String[] TYPE_SEXP_NAMES

The empowerment-type S-Expression values, used by toSExpression() and other methods.

See Also:

toSExpression()

NOT_EMPOWERED

public static final int NOT_EMPOWERED

Initial empowerment type (0).

GRANT

public static final int GRANT

Granting (1).

DELEGATE

public static final int DELEGATE

Delegation (2).

TRANSFER

public static final int TRANSFER

Transfer (3). This is only used in EIntersect algorithm for Tuple reduction.

See Also:

Tuple.EIntersect(Empowerment,Empowerment)

MIN_EMPOWERMENT_VALUE

private static final int MIN_EMPOWERMENT_VALUE

See Also:

GRANT

MAX_EMPOWERMENT_VALUE

private static final int MAX_EMPOWERMENT_VALUE

See Also:

TRANSFER

type

private int type

the empowerment type.

See Also:

GRANT, DELEGATE

PROPAGATE_SEXP_NAMES

public static final String[] PROPAGATE_SEXP_NAMES

The propagate-control S-Expression values, used by toSExpression() and other methods.

See Also:

toSExpression()

NO_PROPAGATION

public static final int NO_PROPAGATION

No propagation allowed (0).

DELEGATEABLE

public static final int DELEGATEABLE

Redelegation allowed (1).

TRANSFERABLE

public static final int TRANSFERABLE

Transfer allowed (2).

MIN_PROPAGATION_VALUE

private static final int MIN_PROPAGATION_VALUE

See Also:

NO_PROPAGATION

MAX_PROPAGATION_VALUE

private static final int MAX_PROPAGATION_VALUE

See Also:

TRANSFERABLE

propagate

private int propagate

the propgation-control type.

See Also:

NO_PROPAGATION, DELEGATEABLE, TRANSFERABLE

Constructor Detail

Empowerment

protected Empowerment()

Don't use me!

See Also:

Empowerment(SExpression), Empowerment(int,int)

Empowerment

public Empowerment(SExpression sexp)
            throws ParseException,
                   SPKIException

Create an immutable Empowerment object from an S-Expression.

See Also:

BaseObj.BaseObj(SExpression)

Empowerment

public Empowerment(int type,
                   int propagate)
            throws SPKIException

Create an immutable Empowerment object from the given empowerment type and, optionally, the propagation-control type.

Parameters:

type - the empowerment type value, must be within the range of MIN_EMPOWERMENT_VALUE and MAX_EMPOWERMENT_VALUE.

propgate - the propagation-control type value, must be within the range of MIN_PROPAGATION_VALUE and MAX_PROPAGATION_VALUE.

Throws:

SPKIException - if something went wrong.

See Also:

GRANT, DELEGATE, NO_PROPAGATION, DELEGATEABLE, TRANSFERABLE

Method Detail

toSExpression

public SExpression toSExpression()
                          throws SPKIException

Description copied from interface: SPKIObject

Build an SExpression representing this object.

Overrides:

toSExpression in class BaseObj

Tags copied from interface: SPKIObject

Returns:

SExpression object representing this object, or null.

Throws:

SPKIException - if something went wrong during conversion.

getEmpowermentType

public int getEmpowermentType()

Get the empowerment type.

Returns:

an integer value representing empowerment type.

See Also:

GRANT, DELEGATE

getPropagationType

public int getPropagationType()

Get the propgation-control type.

Returns:

an integer value representing propagation-control type.

See Also:

NO_PROPAGATION, DELEGATEABLE, TRANSFERABLE