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.dom4j.Document;
24 import org.dom4j.DocumentHelper;
25 import org.dom4j.Element;
26 import org.dom4j.io.DOMReader;
27 import org.dom4j.io.DocumentResult;
28 import org.dom4j.io.DocumentSource;
29 import org.w3c.dom.Node;
30
31 import org.springframework.xml.transform.TransformerObjectSupport;
32
33 /**
34 * Abstract base class for endpoints that handle the message payload as dom4j elements. Offers the message payload as a
35 * dom4j <code>Element</code>, and allows subclasses to create a response by returning an <code>Element</code>.
36 * <p/>
37 * An <code>AbstractDom4JPayloadEndpoint</code> only accept one payload element. Multiple payload elements are not in
38 * accordance with WS-I.
39 *
40 * @author Arjen Poutsma
41 * @see org.dom4j.Element
42 * @since 1.0.0
43 */
44 public abstract class AbstractDom4jPayloadEndpoint 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 DocumentResult}.
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 = null;
59 if (request != null) {
60 DocumentResult dom4jResult = new DocumentResult();
61 transform(request, dom4jResult);
62 requestElement = dom4jResult.getDocument().getRootElement();
63 }
64 Document responseDocument = DocumentHelper.createDocument();
65 Element responseElement = invokeInternal(requestElement, responseDocument);
66 return responseElement != null ? new DocumentSource(responseElement) : null;
67 }
68
69 /**
70 * Returns the payload element of the given source.
71 * <p/>
72 * Default implementation checks whether the source is a {@link javax.xml.transform.dom.DOMSource}, and uses a
73 * {@link org.jdom.input.DOMBuilder} to create a JDOM {@link org.jdom.Element}. In all other cases, or when
74 * {@linkplain #setAlwaysTransform(boolean) alwaysTransform} is {@code true}, the source is transformed into a
75 * {@link org.jdom.transform.JDOMResult}, which is more expensive. If the passed source is {@code null}, {@code
76 * null} is returned.
77 *
78 * @param source the source to return the root element of; can be {@code null}
79 * @return the document element
80 * @throws javax.xml.transform.TransformerException
81 * in case of errors
82 */
83 protected Element getDocumentElement(Source source) throws TransformerException {
84 if (source == null) {
85 return null;
86 }
87 if (!alwaysTransform && source instanceof DOMSource) {
88 Node node = ((DOMSource) source).getNode();
89 if (node.getNodeType() == Node.DOCUMENT_NODE) {
90 DOMReader domReader = new DOMReader();
91 Document document = domReader.read((org.w3c.dom.Document) node);
92 return document.getRootElement();
93 }
94 }
95 // we have no other option than to transform
96 DocumentResult dom4jResult = new DocumentResult();
97 transform(source, dom4jResult);
98 return dom4jResult.getDocument().getRootElement();
99 }
100
101 /**
102 * Template method. Subclasses must implement this. Offers the request payload as a dom4j <code>Element</code>, and
103 * allows subclasses to return a response <code>Element</code>.
104 * <p/>
105 * The given dom4j <code>Document</code> is to be used for constructing a response element, by using
106 * <code>addElement</code>.
107 *
108 * @param requestElement the contents of the SOAP message as dom4j elements
109 * @param responseDocument a dom4j document to be used for constructing a response
110 * @return the response element. Can be <code>null</code> to specify no response.
111 */
112 protected abstract Element invokeInternal(Element requestElement, Document responseDocument) throws Exception;
113 }