1 /*
2 * Copyright 2006 the original author or authors.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package org.springframework.ws.server.endpoint;
18
19 import javax.xml.transform.Source;
20 import javax.xml.transform.TransformerException;
21 import javax.xml.transform.dom.DOMSource;
22
23 import org.jdom.Document;
24 import org.jdom.Element;
25 import org.jdom.input.DOMBuilder;
26 import org.jdom.transform.JDOMResult;
27 import org.jdom.transform.JDOMSource;
28 import org.w3c.dom.Node;
29
30 import org.springframework.xml.transform.TransformerObjectSupport;
31
32 /**
33 * Abstract base class for endpoints that handle the message payload as JDOM elements.
34 * <p/>
35 * <p>Offers the message payload as a JDOM {@link Element}, and allows subclasses to create a response by returning an
36 * <code>Element</code>.
37 * <p/>
38 * <pAn <code>AbstractJDomPayloadEndpoint</code> can accept only <i>one</i> payload element. Multiple payload elements
39 * are not in accordance with WS-I.
40 *
41 * @author Arjen Poutsma
42 * @since 1.0.0
43 */
44 public abstract class AbstractJDomPayloadEndpoint extends TransformerObjectSupport implements PayloadEndpoint {
45
46 private boolean alwaysTransform = false;
47
48 /**
49 * Set if the request {@link Source} should always be transformed into a new {@link JDOMResult}.
50 * <p/>
51 * Default is {@code false}, which is faster.
52 */
53 public void setAlwaysTransform(boolean alwaysTransform) {
54 this.alwaysTransform = alwaysTransform;
55 }
56
57 public final Source invoke(Source request) throws Exception {
58 Element requestElement = getDocumentElement(request);
59 Element responseElement = invokeInternal(requestElement);
60 return responseElement != null ? new JDOMSource(responseElement) : null;
61 }
62
63 /**
64 * Returns the payload element of the given source.
65 * <p/>
66 * Default implementation checks whether the source is a {@link DOMSource}, and uses a {@link DOMBuilder} to create
67 * a JDOM {@link Element}. In all other cases, or when {@linkplain #setAlwaysTransform(boolean) alwaysTransform} is
68 * {@code true}, the source is transformed into a {@link JDOMResult}, which is more expensive. If the passed source
69 * is {@code null}, {@code null} is returned.
70 *
71 * @param source the source to return the root element of; can be {@code null}
72 * @return the document element
73 * @throws TransformerException in case of errors
74 */
75 protected Element getDocumentElement(Source source) throws TransformerException {
76 if (source == null) {
77 return null;
78 }
79 if (!alwaysTransform && source instanceof DOMSource) {
80 Node node = ((DOMSource) source).getNode();
81 DOMBuilder domBuilder = new DOMBuilder();
82 if (node.getNodeType() == Node.ELEMENT_NODE) {
83 return domBuilder.build((org.w3c.dom.Element) node);
84 }
85 else if (node.getNodeType() == Node.DOCUMENT_NODE) {
86 Document document = domBuilder.build((org.w3c.dom.Document) node);
87 return document.getRootElement();
88 }
89 }
90 // we have no other option than to transform
91 JDOMResult jdomResult = new JDOMResult();
92 transform(source, jdomResult);
93 return jdomResult.getDocument().getRootElement();
94 }
95
96 /**
97 * Template method. Subclasses must implement this. Offers the request payload as a JDOM <code>Element</code>, and
98 * allows subclasses to return a response <code>Element</code>.
99 *
100 * @param requestElement the contents of the SOAP message as JDOM element
101 * @return the response element. Can be <code>null</code> to specify no response.
102 */
103 protected abstract Element invokeInternal(Element requestElement) throws Exception;
104 }