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15 * accompanied this code).
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25
26package com.sun.xml.internal.ws.api.message;
27
28import com.sun.istack.internal.NotNull;
29import com.sun.istack.internal.Nullable;
30import com.sun.xml.internal.bind.api.Bridge;
31import com.sun.xml.internal.ws.api.SOAPVersion;
32import com.sun.xml.internal.ws.api.addressing.AddressingVersion;
33import com.sun.xml.internal.ws.api.addressing.WSEndpointReference;
34import com.sun.xml.internal.ws.spi.db.XMLBridge;
35
36import org.xml.sax.ContentHandler;
37import org.xml.sax.ErrorHandler;
38import org.xml.sax.SAXException;
39import org.xml.sax.SAXParseException;
40
41import javax.xml.bind.JAXBException;
42import javax.xml.bind.Unmarshaller;
43import javax.xml.namespace.QName;
44import javax.xml.soap.SOAPException;
45import javax.xml.soap.SOAPMessage;
46import javax.xml.stream.XMLStreamException;
47import javax.xml.stream.XMLStreamReader;
48import javax.xml.stream.XMLStreamWriter;
49import javax.xml.ws.WebServiceException;
50import java.util.Set;
51
52
53/**
54 * A SOAP header.
55 *
56 * <p>
57 * A header is immutable, but unlike body it can be read
58 * multiple times.
59 * The {@link Header} abstraction hides how the header
60 * data is represented in memory; instead, it commits to
61 * the ability to write itself to XML infoset.
62 *
63 * <p>
64 * When a message is received from the transport and
65 * being processed, the processor needs to "peek"
66 * some information of a header, such as the tag name,
67 * the mustUnderstand attribute, and so on. Therefore,
68 * the {@link Header} interface exposes those information
69 * as properties, so that they can be checked without
70 * replaying the infoset, which is efficiently but still
71 * costly.
72 *
73 * <p>
74 * A {@link Header} may belong to more than one {@link HeaderList}
75 * due to wrapping of {@link Message}.
76 *
77 * @see HeaderList
78 * @see Headers
79 */
80public interface Header {
81    // TODO: Vivek pointed out that the only time we are looking at
82    // mustUnderstand and role are when we do the mustUnderstand error check
83    // (that is, to find out if there's any header with @mustUnderstand that
84    // has appropriate role for us.)
85    // if that's the case, it might be better if we define this whole operation
86    // as one method, instead of exposing two properties.
87
88    /**
89     * Checks if this header is ignorable for us (IOW, make sure
90     * that this header has a problematic "mustUnderstand" header value
91     * that we have to reject.)
92     *
93     * <p>
94     * This method is used as a part of the
95     * <a href="HeaderList.html#MU">mustUnderstanx processing</a>.
96     * At the end of the processing, the JAX-WS identifies a list of {@link Header}s
97     * that were not understood. This method is invoked on those {@link Header}s,
98     * to verify that we don't need to report an error for it.
99     *
100     * <p>
101     * specifically, this method has to perform the following tasks:
102     *
103     * <ul>
104     *  <li>If this header does not have {@code mustUnderstand} as "1" nor "true",
105     *      then this method must return true.
106     *  <li>Otherwise, check the role attribute (for SOAP 1.2) or the actor attribute (for SOAP 1.1).
107     *      When those attributes are absent, the default values have to be assumed.
108     *      See {@link #getRole(SOAPVersion)} for how the values are defaulted.
109     *      Now, see if the {@code roles} set contains the value.
110     *      If so, this method must return false (indicating that an error is in order.)
111     *  <li>Otherwise return true (since we don't play the role this header is intended for.)
112     * </ul>
113     *
114     * @param soapVersion
115     *      The caller specifies the SOAP version that the pipeline is working against.
116     *      Often each {@link Header} implementation already knows the SOAP version
117     *      anyway, but this allows some {@link Header}s to avoid keeping it.
118     *      That's why this redundant parameter is passed in.
119     * @param roles
120     *      The set of role values that the current JAX-WS pipeline is assuming.
121     *      Note that SOAP 1.1 and SOAP 1.2 use different strings for the same role,
122     *      and the caller is responsible for supplying a proper value depending on the
123     *      active SOAP version in use.
124     *
125     * @return
126     *      true if no error needs to be reported. False if an error needs to be raised.
127     *      See the method javadoc for more discussion.
128     */
129    public boolean isIgnorable(@NotNull SOAPVersion soapVersion, @NotNull Set<String> roles);
130
131    /**
132     * Gets the value of the soap:role attribute (or soap:actor for SOAP 1.1).
133     *
134     * <p>
135     * If the attribute is omitted, the value defaults to {@link SOAPVersion#implicitRole}.
136     *
137     * @param soapVersion
138     *      The caller specifies the SOAP version that the pipeline is working against.
139     *      Often each {@link Header} implementation already knows the SOAP version
140     *      anyway, but this allows some {@link Header}s to avoid keeping it.
141     *      That's why this redundant parameter is passed in.
142     * @return
143     *      never null. This string need not be interned.
144     */
145    public @NotNull String getRole(@NotNull SOAPVersion soapVersion);
146
147    /**
148     * True if this header is to be relayed if not processed.
149     * For SOAP 1.1 messages, this method always return false.
150     *
151     * <p>
152     * IOW, this method returns true if there's @soap:relay='true'
153     * is present.
154     *
155     * <h3>Implementation Note</h3>
156     * <p>
157     * The implementation needs to check for both "true" and "1",
158     * but because attribute values are normalized, it doesn't have
159     * to consider " true", " 1 ", and so on.
160     *
161     * @return
162     *      false.
163     */
164    public boolean isRelay();
165
166    /**
167     * Gets the namespace URI of this header element.
168     *
169     * @return
170     *      this string must be interned.
171     */
172    public @NotNull String getNamespaceURI();
173
174    /**
175     * Gets the local name of this header element.
176     *
177     * @return
178     *      this string must be interned.
179     */
180    public @NotNull String getLocalPart();
181
182    /**
183     * Gets the attribute value on the header element.
184     *
185     * @param nsUri
186     *      The namespace URI of the attribute. Can be empty.
187     * @param localName
188     *      The local name of the attribute.
189     *
190     * @return
191     *      if the attribute is found, return the whitespace normalized value.
192     *      (meaning no leading/trailing space, no consequtive whitespaces in-between.)
193     *      Otherwise null. Note that the XML parsers are responsible for
194     *      whitespace-normalizing attributes, so {@link Header} implementation
195     *      doesn't have to do anything.
196     */
197    @Nullable String getAttribute(@NotNull String nsUri, @NotNull String localName);
198
199    /**
200     * Gets the attribute value on the header element.
201     *
202     * <p>
203     * This is a convenience method that calls into {@link #getAttribute(String, String)}
204     *
205     * @param name
206     *      Never null.
207     *
208     * @see #getAttribute(String, String)
209     */
210    @Nullable String getAttribute(@NotNull QName name);
211
212    /**
213     * Reads the header as a {@link XMLStreamReader}.
214     *
215     * <p>
216     * The returned parser points at the start element of this header.
217     * (IOW, {@link XMLStreamReader#getEventType()} would return
218     * {@link XMLStreamReader#START_ELEMENT}.
219     *
220     * <h3>Performance Expectation</h3>
221     * <p>
222     * For some {@link Header} implementations, this operation
223     * is a non-trivial operation. Therefore, use of this method
224     * is discouraged unless the caller is interested in reading
225     * the whole header.
226     *
227     * <p>
228     * Similarly, if the caller wants to use this method only to do
229     * the API conversion (such as simply firing SAX events from
230     * {@link XMLStreamReader}), then the JAX-WS team requests
231     * that you talk to us.
232     *
233     * <p>
234     * {@link Message}s that come from tranport usually provides
235     * a reasonably efficient implementation of this method.
236     *
237     * @return
238     *      must not null.
239     */
240    public XMLStreamReader readHeader() throws XMLStreamException;
241
242    /**
243     * Reads the header as a JAXB object by using the given unmarshaller.
244     */
245    public <T> T readAsJAXB(Unmarshaller unmarshaller) throws JAXBException;
246
247    /**
248     * Reads the header as a JAXB object by using the given unmarshaller.
249     * @deprecated
250     */
251    public <T> T readAsJAXB(Bridge<T> bridge) throws JAXBException;
252
253    /**
254     * Reads the header as a data-bond object
255     */
256    public <T> T readAsJAXB(XMLBridge<T> bridge) throws JAXBException;
257
258    /**
259     * Reads this header as an {@link WSEndpointReference}.
260     *
261     * @param expected
262     *      The version of the addressing used to parse the EPR.
263     *      If the actual infoset and this doesn't agree, then
264     *      you'll get an {@link WebServiceException} stating that fact.
265     *
266     * @return
267     *      On a successful return, this method never returns null.
268     */
269    public @NotNull WSEndpointReference readAsEPR(AddressingVersion expected) throws XMLStreamException;
270
271    /**
272     * Writes out the header as a fragment.
273     *
274     * @throws XMLStreamException
275     *      if the operation fails for some reason. This leaves the
276     *      writer to an undefined state.
277     */
278    public void writeTo(XMLStreamWriter w) throws XMLStreamException;
279
280    /**
281     * Writes out the header to the given SOAPMessage.
282     *
283     * <p>
284     * Sometimes a {@link Message} needs to produce itself
285     * as {@link SOAPMessage}, in which case each header needs
286     * to turn itself into a header.
287     *
288     * @throws SOAPException
289     *      if the operation fails for some reason. This leaves the
290     *      writer to an undefined state.
291     */
292    public void writeTo(SOAPMessage saaj) throws SOAPException;
293
294    /**
295     * Writes out the header as SAX events.
296     *
297     * <p>
298     * Sometimes a {@link Message} needs to produce SAX events,
299     * and this method is necessary for headers to participate to it.
300     *
301     * <p>
302     * A header is responsible for producing the SAX events for its part,
303     * including {@code startPrefixMapping} and {@code endPrefixMapping},
304     * but not startDocument/endDocument.
305     *
306     * <p>
307     * Note that SAX contract requires that any error that does NOT originate
308     * from {@link ContentHandler} (meaning any parsing error and etc) must
309     * be first reported to {@link ErrorHandler}. If the SAX event production
310     * cannot be continued and the processing needs to abort, the code may
311     * then throw the same {@link SAXParseException} reported to {@link ErrorHandler}.
312     *
313     * @param contentHandler
314     *      The {@link ContentHandler} that receives SAX events.
315     *
316     * @param errorHandler
317     *      The {@link ErrorHandler} that receives parsing errors.
318     */
319    public void writeTo(ContentHandler contentHandler, ErrorHandler errorHandler) throws SAXException;
320
321    /**
322     * Used to obtain value XYZ from a header that looks like
323     * "&lt;header&gt;XYZ&lt;/header&gt;". The primary use of this header
324     * for now is to access certain Addressing headers quickly.
325     *
326     * @throws WebServiceException
327     *      If the structure of the header is more complicated than
328     *      a simple string header.
329     *
330     * @return
331     *      Can be empty but always non-null.
332     */
333    public @NotNull String getStringContent();
334}
335