com.rsa.certj.xml

Class Transformer

java.lang.Object
  |
  +--com.rsa.certj.xml.Transformer

All Implemented Interfaces:

Cloneable, Serializable

Direct Known Subclasses:

Base64Transformer, C14NTransformer, EnvelopedTransformer, XPATHTransformer

public abstract class Transformer

extends Object

implements Cloneable, Serializable

This class is a base class for different transformers. A transformed element is an optional list of processing steps to apply to the resource's content before it is digested. It can include operations such as canonicalization, encoding/decoding, XPath and XSLT specified by the transformAlgorithm. Supported transforms include: Base64, Canonicalization without comments, Canonicalization with comments, XPath, and Enveloped-Signature.

Copyright © RSA Security Inc., 2001-2002. All rights reserved.

See Also

Serialized Form

Field Summary

static String[]	BASE64_LIST Specifies all supported Base64 transform algorithms as a list of URLs.
static String[]	C14N_LIST Specifies the algorithm name lists for the canonicalization without comments, including all the URLs of the canonicalization specification since June 2000.
static String[]	C14N_WITH_COMMENTS_LIST Specifies the algorithm name lists for the canonicalization with comments, including all the URLs of the canonicalization specification since June 2000.
static String[]	ENVELOPED_SIGNATURE_LIST Specifies all supported Enveloped-Signature transform algorithms as a list of URLs
static String[]	XPATH_LIST Specifies all supported XPath transform algorithms as a list of URLs.

Constructor Summary

Transformer()

Method Summary

static Hashtable	getAllTransformsInfo() Returns the hash table that stores all the supported transformations.
static Transformer	getInstance(String transformAlgorithm) Generates a new Transform object specified by transformAlgorithm.
abstract String	getTransformAlgorithm() Returns the transform algorithm.
abstract byte[]	performTransformation(byte[] input, int inOffset, int inputLength) Applies the transform operation to a byte array input.
abstract org.w3c.dom.NodeList	performTransformation(org.w3c.dom.NodeList inputNodes) This method applies the transform operation to a node-set.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

BASE64_LIST

public static final String[] BASE64_LIST

Specifies all supported Base64 transform algorithms as a list of URLs.

C14N_LIST

public static final String[] C14N_LIST

Specifies the algorithm name lists for the canonicalization without comments, including all the URLs of the canonicalization specification since June 2000.

C14N_WITH_COMMENTS_LIST

public static final String[] C14N_WITH_COMMENTS_LIST

Specifies the algorithm name lists for the canonicalization with comments, including all the URLs of the canonicalization specification since June 2000.

XPATH_LIST

public static final String[] XPATH_LIST

Specifies all supported XPath transform algorithms as a list of URLs.

ENVELOPED_SIGNATURE_LIST

public static final String[] ENVELOPED_SIGNATURE_LIST

Specifies all supported Enveloped-Signature transform algorithms as a list of URLs

Constructor Detail

Transformer

public Transformer()

Method Detail

getAllTransformsInfo

public static Hashtable getAllTransformsInfo()

Returns the hash table that stores all the supported transformations.

Returns

The Hashtable object that stores all the supported Transformer classes.

getTransformAlgorithm

public abstract String getTransformAlgorithm()

Returns the transform algorithm.

Returns

A String object containing the transform algorithm name.

getInstance

public static Transformer getInstance(String transformAlgorithm)
                               throws XMLException

Generates a new Transform object specified by transformAlgorithm. It looks up the internal hash table to determine whether the Transformer class of transformAlgorithm is defined.

Parameters

transformAlgorithm

A URL string specifying the name of the transform algorithm.

Returns

The Transformer object specified by the transformAlgorithm.

Throws

XMLException - If an error occurs while instantiating a Transformer object.

performTransformation

public abstract byte[] performTransformation(byte[] input,
                                             int inOffset,
                                             int inputLength)
                                      throws XMLException

Applies the transform operation to a byte array input. Transforms such as Base64 should use this method.

Parameters

	input		The byte array to transform.
	inOffset		The starting position of the data to transform in input.
	inputLength		The length of the data to transform in input.

Returns

A byte array that contains the transformation.

Throws

XMLException - If an error occurs while performing the transformation.

performTransformation

public abstract org.w3c.dom.NodeList performTransformation(org.w3c.dom.NodeList inputNodes)
                                                    throws XMLException

This method applies the transform operation to a node-set. Transforms such as XPath should use this method.

Parameters

inputNodes

A Node object to transform.

Returns

A NodeList object containing the transformed data.

Throws

XMLException - If an error occurs during the transformation.