/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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 javax.xml.soap;

/**
 * The container for the SOAPHeader and SOAPBody portions of a <CODE>SOAPPart</CODE> object. By
 * default, a <CODE> SOAPMessage</CODE> object is created with a <CODE> SOAPPart</CODE> object that
 * has a <CODE>SOAPEnvelope</CODE> object. The <CODE>SOAPEnvelope</CODE> object by default has an
 * empty <CODE>SOAPBody</CODE> object and an empty <CODE> SOAPHeader</CODE> object. The
 * <CODE>SOAPBody</CODE> object is required, and the <CODE>SOAPHeader</CODE> object, though
 * optional, is used in the majority of cases. If the <CODE> SOAPHeader</CODE> object is not needed,
 * it can be deleted, which is shown later.</P>
 * <p/>
 * <P>A client can access the <CODE>SOAPHeader</CODE> and <CODE> SOAPBody</CODE> objects by calling
 * the methods <CODE> SOAPEnvelope.getHeader</CODE> and <CODE> SOAPEnvelope.getBody</CODE>. The
 * following lines of code use these two methods after starting with the <CODE> SOAPMessage</CODE>
 * object <I>message</I> to get the <CODE> SOAPPart</CODE> object <I>sp</I>, which is then used to
 * get the <CODE>SOAPEnvelope</CODE> object <I>se</I>.</P> <PRE> SOAPPart sp =
 * message.getSOAPPart(); SOAPEnvelope se = sp.getEnvelope(); SOAPHeader sh = se.getHeader();
 * SOAPBody sb = se.getBody(); </PRE>
 * <p/>
 * <P>It is possible to change the body or header of a <CODE> SOAPEnvelope</CODE> object by
 * retrieving the current one, deleting it, and then adding a new body or header. The <CODE>
 * javax.xml.soap.Node</CODE> method <CODE>detachNode</CODE> detaches the XML element (node) on
 * which it is called. For example, the following line of code deletes the <CODE> SOAPBody</CODE>
 * object that is retrieved by the method <CODE> getBody</CODE>.</P> <PRE>
 * se.getBody().detachNode(); </PRE> To create a <CODE>SOAPHeader</CODE> object to replace the one
 * that was removed, a client uses the method <CODE> SOAPEnvelope.addHeaderBlock</CODE>, which
 * creates a new header and adds it to the <CODE>SOAPEnvelope</CODE> object. Similarly, the method
 * <CODE>addBody</CODE> creates a new <CODE>SOAPBody</CODE> object and adds it to the
 * <CODE>SOAPEnvelope</CODE> object. The following code fragment retrieves the current header,
 * removes it, and adds a new one. Then it retrieves the current body, removes it, and adds a new
 * one. <PRE> SOAPPart sp = message.getSOAPPart(); SOAPEnvelope se = sp.getEnvelope();
 * se.getHeader().detachNode(); SOAPHeader sh = se.addHeaderBlock(); se.getBody().detachNode();
 * SOAPBody sb = se.addBody(); </PRE> It is an error to add a <CODE>SOAPBody</CODE> or <CODE>
 * SOAPHeader</CODE> object if one already exists.
 * <p/>
 * <P>The <CODE>SOAPEnvelope</CODE> interface provides three methods for creating <CODE>Name</CODE>
 * objects. One method creates <CODE>Name</CODE> objects with a local name, a namespace prefix, and
 * a namesapce URI. The second method creates <CODE>Name</CODE> objects with a local name and a
 * namespace prefix, and the third creates <CODE>Name</CODE> objects with just a local name. The
 * following line of code, in which <I>se</I> is a <CODE>SOAPEnvelope</CODE> object, creates a new
 * <CODE>Name</CODE> object with all three.</P> <PRE> Name name = se.createName("GetLastTradePrice",
 * "WOMBAT", "http://www.wombat.org/trader"); </PRE>
 */
public interface SOAPEnvelope extends SOAPElement {

    /**
     * Creates a new <CODE>Name</CODE> object initialized with the given local name, namespace
     * prefix, and namespace URI.
     * <p/>
     * <P>This factory method creates <CODE>Name</CODE> objects for use in the SOAP/XML document.
     *
     * @param localName a <CODE>String</CODE> giving the local name
     * @param prefix    a <CODE>String</CODE> giving the prefix of the namespace
     * @param uri       a <CODE>String</CODE> giving the URI of the namespace
     * @return a <CODE>Name</CODE> object initialized with the given local name, namespace prefix,
     *         and namespace URI
     * @throws SOAPException if there is a SOAP error
     */
    public abstract Name createName(String localName,
                                    String prefix,
                                    String uri)
            throws SOAPException;

    /**
     * Creates a new <CODE>Name</CODE> object initialized with the given local name.
     * <p/>
     * <P>This factory method creates <CODE>Name</CODE> objects for use in the SOAP/XML document.
     *
     * @param localName a <CODE>String</CODE> giving the local name
     * @return a <CODE>Name</CODE> object initialized with the given local name
     * @throws SOAPException if there is a SOAP error
     */
    public abstract Name createName(String localName) throws SOAPException;

    /**
     * Returns the <CODE>SOAPHeader</CODE> object for this <CODE> SOAPEnvelope</CODE> object.
     * <p/>
     * <P>A new <CODE>SOAPMessage</CODE> object is by default created with a
     * <CODE>SOAPEnvelope</CODE> object that contains an empty <CODE>SOAPHeader</CODE> object. As a
     * result, the method <CODE>getHeader</CODE> will always return a <CODE>SOAPHeader</CODE> object
     * unless the header has been removed and a new one has not been added.
     *
     * @return the <CODE>SOAPHeader</CODE> object or <CODE> null</CODE> if there is none
     * @throws SOAPException if there is a problem obtaining the <CODE>SOAPHeader</CODE> object
     */
    public abstract SOAPHeader getHeader() throws SOAPException;

    /**
     * Returns the <CODE>SOAPBody</CODE> object associated with this <CODE>SOAPEnvelope</CODE>
     * object.
     * <p/>
     * <P>A new <CODE>SOAPMessage</CODE> object is by default created with a
     * <CODE>SOAPEnvelope</CODE> object that contains an empty <CODE>SOAPBody</CODE> object. As a
     * result, the method <CODE>getBody</CODE> will always return a <CODE>SOAPBody</CODE> object
     * unless the body has been removed and a new one has not been added.
     *
     * @return the <CODE>SOAPBody</CODE> object for this <CODE> SOAPEnvelope</CODE> object or
     *         <CODE>null</CODE> if there is none
     * @throws SOAPException if there is a problem obtaining the <CODE>SOAPBody</CODE> object
     */
    public abstract SOAPBody getBody() throws SOAPException;

    /**
     * Creates a <CODE>SOAPHeader</CODE> object and sets it as the <CODE>SOAPHeader</CODE> object
     * for this <CODE> SOAPEnvelope</CODE> object.
     * <p/>
     * <P>It is illegal to add a header when the envelope already contains a header. Therefore, this
     * method should be called only after the existing header has been removed.
     *
     * @return the new <CODE>SOAPHeader</CODE> object
     * @throws SOAPException if this <CODE> SOAPEnvelope</CODE> object already contains a valid
     *                       <CODE>SOAPHeader</CODE> object
     */
    public abstract SOAPHeader addHeader() throws SOAPException;

    /**
     * Creates a <CODE>SOAPBody</CODE> object and sets it as the <CODE>SOAPBody</CODE> object for
     * this <CODE> SOAPEnvelope</CODE> object.
     * <p/>
     * <P>It is illegal to add a body when the envelope already contains a body. Therefore, this
     * method should be called only after the existing body has been removed.
     *
     * @return the new <CODE>SOAPBody</CODE> object
     * @throws SOAPException if this <CODE> SOAPEnvelope</CODE> object already contains a valid
     *                       <CODE>SOAPBody</CODE> object
     */
    public abstract SOAPBody addBody() throws SOAPException;
}