spki
Class BaseObj

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

Direct Known Subclasses:

AuthorizationRequest, CertBody, Certificate, Date, Empowerment, Escrow, Hash, Issuer, Name, PrivateKey, PublicKey, RegistrationRequest, Sequence, SequenceDef, SequenceRef, Signature, Subject, Tag, URIs, Validity, ValidOffline, ValidOnline

public abstract class BaseObj

extends Object

implements SPKIObject

Top-level spki abstract class.

all classes in spki package extend from this abstract class.

Version:

$Id: BaseObj.java,v 1.19 2002/06/24 18:03:20 tep Exp $

Author:

Tep Narula <tep@win.trlabs.ca>, adapted from SPKI.SPKIBase by Per Harald Myrvang <perm@pasta.cs.uit.no>

Field Summary

private static String	__ME This class's full name.
private boolean	cache_sexp Is S-Expression caching enabled? true by default.
private SExpression	cached_sexp Cached S-Expression of this object.
static String	DEFAULT_HASH_ALG Default hash algorithm (sha1).
private boolean	locked is this object immutable? false by default.
static String	SEXP_NAME This class S-Expression type name, used by toSExpression() and other methods.

Constructor Summary

protected	BaseObj() Default constructor.
protected	BaseObj(SExpression sexp) Create an immutable SPKI object from an S-Expression.

Method Summary

void	disableSExpressionCaching() Disable caching of SExpression.
void	enableSExpressionCaching() Enable caching of SExpression given by the constructor or built by a called to the toSExpression() method.
static String	extractHashAlgId(String id) Extracts the hash-alg-id from a SPKI sig-alg-id.
protected SExpression	getCachedSExpression() Get this object's cached SExpression list.
boolean	isLocked() See if this object is locked, i.e immutable.
static boolean	isSListOfType(SExpression sexp, String type, boolean doException) Checks that an SExpression is both a list and of the given type.
void	lock() Make this object immutable.
static String	providerToSPKI(String id) Converts a [I]JCA provider string to a SPKI sig-alg-id.
protected void	setCachedSExpression(SExpression sexp) Cache this object's SExpression list if caching is enabled and a) this object is not immutable or b) the cache is still empty.
static String	spkiToProvider(String id) Converts a SPKI sig-alg-id to the [I]JCL provider string.
abstract SExpression	toSExpression() Build an SExpression representing this object.
String	toString() Return this object as a string, or null.

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. Must be overridden by all subclasses.

See Also:

toSExpression()

DEFAULT_HASH_ALG

public static final String DEFAULT_HASH_ALG

Default hash algorithm (sha1).

cache_sexp

private boolean cache_sexp

Is S-Expression caching enabled? true by default.

See Also:

enableSExpressionCaching(), disableSExpressionCaching()

cached_sexp

private SExpression cached_sexp

Cached S-Expression of this object.

See Also:

setCachedSExpression(SExpression), getCachedSExpression()

locked

private boolean locked

is this object immutable? false by default.

See Also:

lock(), isLocked()

Constructor Detail

BaseObj

protected BaseObj()

Default constructor.

BaseObj

protected BaseObj(SExpression sexp)
           throws ParseException,
                  SPKIException

Create an immutable SPKI object from an S-Expression. Must be overridden by all subclasses.

Parameters:

sexp - SExpression object containing existing SPKI object.

Throws:

ParseException - if some error occured during parsing.

SPKIException - if some error occured during creation.

Method Detail

toString

public String toString()

Return this object as a string, or null. The default action of this method is to call return this.toSExpression().toString().

Overrides:

toString in class Object

Returns:

SExpression list containing this object in Advanced form, or null if something went wrong.

See Also:

toSExpression()

lock

public final void lock()

Description copied from interface: SPKIObject

Make this object immutable. This is supposed to be non-reversible, so don't implement something stupid like unLock() ok?. Multiple locks are allowed, though.

Specified by:

lock in interface SPKIObject

Tags copied from interface: SPKIObject

See Also:

SPKIObject.isLocked()

isLocked

public final boolean isLocked()

Description copied from interface: SPKIObject

See if this object is locked, i.e immutable.

Specified by:

isLocked in interface SPKIObject

Tags copied from interface: SPKIObject

Returns:

true if this object is locked, or false otherwise.

See Also:

SPKIObject.lock()

toSExpression

public abstract SExpression toSExpression()
                                   throws SPKIException

Description copied from interface: SPKIObject

Build an SExpression representing this object.

Specified by:

toSExpression in interface SPKIObject

Tags copied from interface: SPKIObject

Returns:

SExpression object representing this object, or null.

Throws:

SPKIException - if something went wrong during conversion.

isSListOfType

public static final boolean isSListOfType(SExpression sexp,
                                          String type,
                                          boolean doException)
                                   throws SPKIException

Checks that an SExpression is both a list and of the given type. Where by "type" we mean a match of the element at index 0.

Parameters:

sexp - SExpression to check

type - String containing the type to check for

doException - true if this method is allowed to throw exceptions when matching fails, false if the caller wants to handle it herself (in that case, check the return value).

Returns:

true if all is ok, false if not.

Throws:

ParseException - if both doException was set to true and the match failed.

extractHashAlgId

public static final String extractHashAlgId(String id)

Extracts the hash-alg-id from a SPKI sig-alg-id.

spkiToProvider

public static final String spkiToProvider(String id)

Converts a SPKI sig-alg-id to the [I]JCL provider string.

providerToSPKI

public static final String providerToSPKI(String id)

Converts a [I]JCA provider string to a SPKI sig-alg-id.

enableSExpressionCaching

public final void enableSExpressionCaching()

Enable caching of SExpression given by the constructor or built by a called to the toSExpression() method. This trades off memory consumption for faster processing.

See Also:

disableSExpressionCaching(), BaseObj(SExpression), toSExpression(), setCachedSExpression(SExpression), getCachedSExpression()

disableSExpressionCaching

public final void disableSExpressionCaching()

Disable caching of SExpression. This trades off processing time for lower memory consumption.

See Also:

enableSExpressionCaching(), setCachedSExpression(SExpression), getCachedSExpression()

setCachedSExpression

protected final void setCachedSExpression(SExpression sexp)

Cache this object's SExpression list if caching is enabled and a) this object is not immutable or b) the cache is still empty. It clones the passed SExpression and store the copy to prevent external tampering.

Parameters:

sexp - the SExpression to be cached.

See Also:

enableSExpressionCaching(), disableSExpressionCaching(), getCachedSExpression()

getCachedSExpression

protected final SExpression getCachedSExpression()

Get this object's cached SExpression list. It returns a copy of the cached SExpression list (stored by an earlier call to setCachedSExpression()) to prevent external tampering, or null if the cache is empty.

Returns:

SExpression list containing this object, or null.

See Also:

enableSExpressionCaching(), disableSExpressionCaching(), setCachedSExpression(SExpression)