/* * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. *//* * $Id: Transform.java,v 1.5 2005/05/10 16:03:48 mullan Exp $ */package javax.xml.crypto.dsig; import java.io.OutputStream;import java.security.spec.AlgorithmParameterSpec;import javax.xml.crypto.AlgorithmMethod;import javax.xml.crypto.Data;import javax.xml.crypto.OctetStreamData;import javax.xml.crypto.XMLCryptoContext;import javax.xml.crypto.XMLStructure;import javax.xml.crypto.dsig.spec.TransformParameterSpec; /** * A representation of the XML <code>Transform</code> element as * defined in the <a href="http://www.w3.org/TR/xmldsig-core/"> * W3C Recommendation for XML-Signature Syntax and Processing</a>. * The XML Schema Definition is defined as: * * <pre> * &lt;element name="Transform" type="ds:TransformType"/&gt; *   &lt;complexType name="TransformType" mixed="true"&gt; *     &lt;choice minOccurs="0" maxOccurs="unbounded"&gt; *       &lt;any namespace="##other" processContents="lax"/&gt; *       &lt;!-- (1,1) elements from (0,unbounded) namespaces --&gt; *       &lt;element name="XPath" type="string"/&gt; *     &lt;/choice&gt; *     &lt;attribute name="Algorithm" type="anyURI" use="required"/&gt; *   &lt;/complexType&gt; * </pre> * * A <code>Transform</code> instance may be created by invoking the * {@link XMLSignatureFactory#newTransform newTransform} method * of the {@link XMLSignatureFactory} class. * * @author Sean Mullan * @author JSR 105 Expert Group * @since 1.6 * @see XMLSignatureFactory#newTransform(String, TransformParameterSpec) */public interface Transform extends XMLStructure, AlgorithmMethod {     /**     * The <a href="http://www.w3.org/2000/09/xmldsig#base64">Base64</a>     * transform algorithm URI.     */    final static String BASE64 = "http://www.w3.org/2000/09/xmldsig#base64";     /**     * The <a href="http://www.w3.org/2000/09/xmldsig#enveloped-signature">     * Enveloped Signature</a> transform algorithm URI.     */    final static String ENVELOPED =        "http://www.w3.org/2000/09/xmldsig#enveloped-signature";     /**     * The <a href="http://www.w3.org/TR/1999/REC-xpath-19991116">XPath</a>     * transform algorithm URI.     */    final static String XPATH = "http://www.w3.org/TR/1999/REC-xpath-19991116";     /**     * The <a href="http://www.w3.org/2002/06/xmldsig-filter2">     * XPath Filter 2</a> transform algorithm URI.     */    final static String XPATH2 = "http://www.w3.org/2002/06/xmldsig-filter2";     /**     * The <a href="http://www.w3.org/TR/1999/REC-xslt-19991116">XSLT</a>     * transform algorithm URI.     */    final static String XSLT = "http://www.w3.org/TR/1999/REC-xslt-19991116";     /**     * Returns the algorithm-specific input parameters associated with this     * <code>Transform</code>.     * <p>     * The returned parameters can be typecast to a     * {@link TransformParameterSpec} object.     *     * @return the algorithm-specific input parameters (may be <code>null</code>     *    if not specified)     */    AlgorithmParameterSpec getParameterSpec();     /**     * Transforms the specified data using the underlying transform algorithm.     *     * @param data the data to be transformed     * @param context the <code>XMLCryptoContext</code> containing     *    additional context (may be <code>null</code> if not applicable)     * @return the transformed data     * @throws NullPointerException if <code>data</code> is <code>null</code>     * @throws TransformException if an error occurs while executing the     *    transform     */    public abstract Data transform(Data data, XMLCryptoContext context)        throws TransformException;     /**     * Transforms the specified data using the underlying transform algorithm.     * If the output of this transform is an <code>OctetStreamData</code>, then     * this method returns <code>null</code> and the bytes are written to the     * specified <code>OutputStream</code>. Otherwise, the     * <code>OutputStream</code> is ignored and the method behaves as if     * {@link #transform(Data, XMLCryptoContext)} were invoked.     *     * @param data the data to be transformed     * @param context the <code>XMLCryptoContext</code> containing     *    additional context (may be <code>null</code> if not applicable)     * @param os the <code>OutputStream</code> that should be used to write     *    the transformed data to     * @return the transformed data (or <code>null</code> if the data was     *    written to the <code>OutputStream</code> parameter)     * @throws NullPointerException if <code>data</code> or <code>os</code>     *    is <code>null</code>     * @throws TransformException if an error occurs while executing the     *    transform     */    public abstract Data transform        (Data data, XMLCryptoContext context, OutputStream os)        throws TransformException;}