/xml-security-1_4_5/src/org/apache/xml/security/transforms/Transform.java
Java | 362 lines | 177 code | 43 blank | 142 comment | 21 complexity | e4612b5cb5eb3d9d9ae3322c278637b5 MD5 | raw file
Possible License(s): Apache-2.0
- /*
- * Copyright 1999-2009 The Apache Software Foundation.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
- package org.apache.xml.security.transforms;
- import java.io.IOException;
- import java.io.OutputStream;
- import java.util.HashMap;
- import javax.xml.parsers.ParserConfigurationException;
- import org.apache.xml.security.c14n.CanonicalizationException;
- import org.apache.xml.security.c14n.InvalidCanonicalizerException;
- import org.apache.xml.security.exceptions.AlgorithmAlreadyRegisteredException;
- import org.apache.xml.security.exceptions.XMLSecurityException;
- import org.apache.xml.security.signature.XMLSignatureInput;
- import org.apache.xml.security.utils.ClassLoaderUtils;
- import org.apache.xml.security.utils.Constants;
- import org.apache.xml.security.utils.HelperNodeList;
- import org.apache.xml.security.utils.SignatureElementProxy;
- import org.apache.xml.security.utils.XMLUtils;
- import org.w3c.dom.Document;
- import org.w3c.dom.Element;
- import org.w3c.dom.NodeList;
- import org.xml.sax.SAXException;
- /**
- * Implements the behaviour of the <code>ds:Transform</code> element.
- *
- * This <code>Transform</code>(Factory) class acts as the Factory and Proxy of
- * the implementing class that supports the functionality of <a
- * href=http://www.w3.org/TR/xmldsig-core/#sec-TransformAlg>a Transform
- * algorithm</a>.
- * Implements the Factory and Proxy pattern for ds:Transform algorithms.
- *
- * @author Christian Geuer-Pollmann
- * @see Transforms
- * @see TransformSpi
- */
- public final class Transform extends SignatureElementProxy {
- /** {@link org.apache.commons.logging} logging facility */
- private static org.apache.commons.logging.Log log =
- org.apache.commons.logging.LogFactory.getLog(Transform.class.getName());
- /** Field _alreadyInitialized */
- private static boolean alreadyInitialized = false;
- /** All available Transform classes are registered here */
- private static HashMap transformClassHash = null;
-
- private static HashMap transformSpiHash = new HashMap();
- private TransformSpi transformSpi = null;
- /**
- * Constructs {@link Transform}
- *
- * @param doc the {@link Document} in which <code>Transform</code> will be
- * placed
- * @param algorithmURI URI representation of
- * <code>Transform algorithm</code> which will be specified as parameter of
- * {@link #getInstance(Document, String)}, when generated. </br>
- * @param contextNodes the child node list of <code>Transform</code> element
- * @throws InvalidTransformException
- */
- public Transform(Document doc, String algorithmURI, NodeList contextNodes)
- throws InvalidTransformException {
- super(doc);
- this._constructionElement.setAttributeNS
- (null, Constants._ATT_ALGORITHM, algorithmURI);
- transformSpi = getTransformSpi(algorithmURI);
- if (transformSpi == null) {
- Object exArgs[] = { algorithmURI };
- throw new InvalidTransformException(
- "signature.Transform.UnknownTransform", exArgs);
- }
- if (log.isDebugEnabled()) {
- log.debug("Create URI \"" + algorithmURI + "\" class \""
- + transformSpi.getClass() + "\"");
- log.debug("The NodeList is " + contextNodes);
- }
- // give it to the current document
- if (contextNodes != null) {
- for (int i = 0; i < contextNodes.getLength(); i++) {
- this._constructionElement.appendChild
- (contextNodes.item(i).cloneNode(true));
- }
- }
- }
- /**
- * This constructor can only be called from the {@link Transforms} object,
- * so it's protected.
- *
- * @param element <code>ds:Transform</code> element
- * @param BaseURI the URI of the resource where the XML instance was stored
- * @throws InvalidTransformException
- * @throws TransformationException
- * @throws XMLSecurityException
- */
- public Transform(Element element, String BaseURI)
- throws InvalidTransformException, TransformationException,
- XMLSecurityException {
- super(element, BaseURI);
- // retrieve Algorithm Attribute from ds:Transform
- String algorithmURI = element.getAttributeNS(null, Constants._ATT_ALGORITHM);
- if (algorithmURI == null || algorithmURI.length() == 0) {
- Object exArgs[] = { Constants._ATT_ALGORITHM,
- Constants._TAG_TRANSFORM };
- throw new TransformationException("xml.WrongContent", exArgs);
- }
-
- transformSpi = getTransformSpi(algorithmURI);
- if (transformSpi == null) {
- Object exArgs[] = { algorithmURI };
- throw new InvalidTransformException(
- "signature.Transform.UnknownTransform", exArgs);
- }
- }
- /**
- * Generates a Transform object that implements the specified
- * <code>Transform algorithm</code> URI.
- *
- * @param algorithmURI <code>Transform algorithm</code> URI representation,
- * such as specified in
- * <a href=http://www.w3.org/TR/xmldsig-core/#sec-TransformAlg>Transform algorithm </a>
- * @param doc the proxy {@link Document}
- * @return <code>{@link Transform}</code> object
- * @throws InvalidTransformException
- */
- public static Transform getInstance(
- Document doc, String algorithmURI) throws InvalidTransformException {
- return getInstance(doc, algorithmURI, (NodeList) null);
- }
- /**
- * Generates a Transform object that implements the specified
- * <code>Transform algorithm</code> URI.
- *
- * @param algorithmURI <code>Transform algorithm</code> URI representation,
- * such as specified in
- * <a href=http://www.w3.org/TR/xmldsig-core/#sec-TransformAlg>Transform algorithm </a>
- * @param contextChild the child element of <code>Transform</code> element
- * @param doc the proxy {@link Document}
- * @return <code>{@link Transform}</code> object
- * @throws InvalidTransformException
- */
- public static Transform getInstance(
- Document doc, String algorithmURI, Element contextChild)
- throws InvalidTransformException {
- HelperNodeList contextNodes = null;
-
- if (contextChild != null) {
- contextNodes = new HelperNodeList();
-
- XMLUtils.addReturnToElement(doc, contextNodes);
- contextNodes.appendChild(contextChild);
- XMLUtils.addReturnToElement(doc, contextNodes);
- }
- return getInstance(doc, algorithmURI, contextNodes);
- }
- /**
- * Generates a Transform object that implements the specified
- * <code>Transform algorithm</code> URI.
- *
- * @param algorithmURI <code>Transform algorithm</code> URI form, such as
- * specified in <a href=http://www.w3.org/TR/xmldsig-core/#sec-TransformAlg>
- * Transform algorithm </a>
- * @param contextNodes the child node list of <code>Transform</code> element
- * @param doc the proxy {@link Document}
- * @return <code>{@link Transform}</code> object
- * @throws InvalidTransformException
- */
- public static Transform getInstance(
- Document doc, String algorithmURI, NodeList contextNodes)
- throws InvalidTransformException {
- return new Transform(doc, algorithmURI, contextNodes);
- }
- /**
- * Initalizes for this {@link Transform}.
- */
- public static void init() {
- if (!alreadyInitialized) {
- transformClassHash = new HashMap(10);
- alreadyInitialized = true;
- }
- }
- /**
- * Registers implementing class of the Transform algorithm with algorithmURI
- *
- * @param algorithmURI algorithmURI URI representation of
- * <code>Transform algorithm</code> will be specified as parameter of
- * {@link #getInstance(Document, String)}, when generate. </br>
- * @param implementingClass <code>implementingClass</code> the implementing
- * class of {@link TransformSpi}
- * @throws AlgorithmAlreadyRegisteredException if specified algorithmURI
- * is already registered
- */
- public static void register(String algorithmURI, String implementingClass)
- throws AlgorithmAlreadyRegisteredException {
- // are we already registered?
- Class registeredClass = getImplementingClass(algorithmURI);
- if ((registeredClass != null) ) {
- Object exArgs[] = { algorithmURI, registeredClass };
- throw new AlgorithmAlreadyRegisteredException(
- "algorithm.alreadyRegistered", exArgs);
- }
- try {
- transformClassHash.put
- (algorithmURI, ClassLoaderUtils.loadClass(implementingClass, Transform.class));
- } catch (ClassNotFoundException e) {
- throw new RuntimeException(e);
- }
- }
- /**
- * Returns the URI representation of Transformation algorithm
- *
- * @return the URI representation of Transformation algorithm
- */
- public String getURI() {
- return this._constructionElement.getAttributeNS
- (null, Constants._ATT_ALGORITHM);
- }
- /**
- * Transforms the input, and generates {@link XMLSignatureInput} as output.
- *
- * @param input input {@link XMLSignatureInput} which can supplied Octet
- * Stream and NodeSet as Input of Transformation
- * @return the {@link XMLSignatureInput} class as the result of
- * transformation
- * @throws CanonicalizationException
- * @throws IOException
- * @throws InvalidCanonicalizerException
- * @throws TransformationException
- */
- public XMLSignatureInput performTransform(XMLSignatureInput input)
- throws IOException, CanonicalizationException,
- InvalidCanonicalizerException, TransformationException {
- XMLSignatureInput result = null;
- try {
- result = transformSpi.enginePerformTransform(input, this);
- } catch (ParserConfigurationException ex) {
- Object exArgs[] = { this.getURI(), "ParserConfigurationException" };
- throw new CanonicalizationException(
- "signature.Transform.ErrorDuringTransform", exArgs, ex);
- } catch (SAXException ex) {
- Object exArgs[] = { this.getURI(), "SAXException" };
- throw new CanonicalizationException(
- "signature.Transform.ErrorDuringTransform", exArgs, ex);
- }
- return result;
- }
-
- /**
- * Transforms the input, and generates {@link XMLSignatureInput} as output.
- *
- * @param input input {@link XMLSignatureInput} which can supplied Octect
- * Stream and NodeSet as Input of Transformation
- * @param os where to output the result of the last transformation
- * @return the {@link XMLSignatureInput} class as the result of
- * transformation
- * @throws CanonicalizationException
- * @throws IOException
- * @throws InvalidCanonicalizerException
- * @throws TransformationException
- */
- public XMLSignatureInput performTransform(XMLSignatureInput input,
- OutputStream os) throws IOException, CanonicalizationException,
- InvalidCanonicalizerException, TransformationException {
- XMLSignatureInput result = null;
- try {
- result = transformSpi.enginePerformTransform(input, os, this);
- } catch (ParserConfigurationException ex) {
- Object exArgs[] = { this.getURI(), "ParserConfigurationException" };
- throw new CanonicalizationException(
- "signature.Transform.ErrorDuringTransform", exArgs, ex);
- } catch (SAXException ex) {
- Object exArgs[] = { this.getURI(), "SAXException" };
- throw new CanonicalizationException(
- "signature.Transform.ErrorDuringTransform", exArgs, ex);
- }
- return result;
- }
- /**
- * Method getImplementingClass
- *
- * @param URI
- * @return The name of the class implementing the URI.
- */
- private static Class getImplementingClass(String URI) {
- return (Class) transformClassHash.get(URI);
- }
- private static TransformSpi getTransformSpi(String URI)
- throws InvalidTransformException {
- try {
- Object value = transformSpiHash.get(URI);
- if (value != null) {
- return (TransformSpi) value;
- }
- Class cl = (Class) transformClassHash.get(URI);
- if (cl != null) {
- TransformSpi tr = (TransformSpi) cl.newInstance();
- transformSpiHash.put(URI, tr);
- return tr;
- }
- } catch (InstantiationException ex) {
- Object exArgs[] = { URI };
- throw new InvalidTransformException(
- "signature.Transform.UnknownTransform", exArgs, ex);
- } catch (IllegalAccessException ex) {
- Object exArgs[] = { URI };
- throw new InvalidTransformException(
- "signature.Transform.UnknownTransform", exArgs, ex);
- }
- return null;
- }
-
- /** @inheritDoc */
- public String getBaseLocalName() {
- return Constants._TAG_TRANSFORM;
- }
- }