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 * published by the Free Software Foundation.  Oracle designates this

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 * by Oracle in the LICENSE file that accompanied this code.

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 * This code is distributed in the hope that it will be useful, but WITHOUT

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 * 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,

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package com.sun.xml.internal.bind.v2.runtime.output;

import java.io.IOException;

import javax.xml.bind.JAXBContext;

import javax.xml.stream.XMLStreamException;

import com.sun.xml.internal.bind.v2.runtime.Name;

import com.sun.xml.internal.bind.v2.runtime.NameList;

import com.sun.xml.internal.bind.v2.runtime.XMLSerializer;

import org.xml.sax.SAXException;

/**

 * Well-formed XML writer.

 *

 * <p>

 * Implementations of this interface is used to connect {@link XMLSerializer}

 * to the actual target. This allows {@link XMLSerializer} to be API agnostic.

 *

 *

 * <h2>Notes</h2>

 * <p>

 * {@link JAXBContext} assigns indices to URIs and local names

 * that are statically known by using {@link NameList}.

 * {@link XmlOutput} implementation can use these indices to improve

 * the performance. For example, those namespace URI indices can be

 * turned into prefixes quickly.

 *

 * <p>

 * {@link XmlOutput} still allows arbitrary namepsace URIs / local names

 * to be written.

 *

 * <p>

 * The {@link NamespaceContextImpl} object, which is shared between {@link XmlOutput} and

 * {@link XMLSerializer}, keeps track of the in-scope namespace bindings. By the time

 * the {@link #beginStartTag} method is called, all the namespace bindings for the new

 * element is already declared. Similarly, after the {@link #endTag} method is called,

 * in-scope bindings will be removed. This book keeping is all done outside {@link XmlOutput}.

 *

 * <p>

 * {@link XmlOutput} and {@link XMLSerializer} uses indices to

 * reference prefixes/URIs to be written. {@link NamespaceContextImpl} can

 * convert prefix indices to URIs and the string representations of prefixes.

 * Binding from indices to URIs and prefixes do not change while indices

 * are "in scope", so {@link XmlOutput} is again expected to take advantage of

 * this to improve the perofmrnace.

 *

 * <p>

 * prefix index 0 is reserved for "xml", and this binding is assumed to be always there.

 * {@link NamespaceContextImpl} can handle this index correctly, but this binding will never

 * be reported to {@link XmlOutput} through {@link #beginStartTag}.

 *

 * <p>

 * One pecurilar behavior of a {@link NamespaceContextImpl} object is that it tries

 * to define redundant xmlns="" on the root element. Implementations of {@link XmlOutput}

 * is encouraged to check for this and avoid generating redundant namespace declarations.

 *

 *

 *

 * <h2>Call Sequence</h2>

 * <p>

 * {@link XMLSerializer} calls the writer methods in the following order:

 *

 * <pre>

 * CALLSEQUENCE  :=  {@link #startDocument startDocument} ELEMENT {@link #endDocument endDocument}

 *               |   ELEMENT   // for fragment

 *

 * ELEMENT       :=  {@link #beginStartTag beginStartTag} {@link #attribute attribute}* {@link #endStartTag endStartTag} CONTENTS {@link #endTag endTag}

 *

 * CONTENTS      :=  (ELEMENT | {@link #text text})*

 * </pre>

 *

 * TODO: for FI, consider making attribute values from Strings to CharSequences.

 *

 * @author Kohsuke Kawaguchi

 */

public interface XmlOutput {

//

//

// Contracts

//

//

    /**

     * Called at the very beginning.

     *

     * @param serializer

     *      the {@link XMLSerializer} that coordinates this whole marshalling episode.

     * @param fragment

     *      true if we are marshalling a fragment.

     */

    public void startDocument(XMLSerializer serializer, boolean fragment, int[] nsUriIndex2prefixIndex, NamespaceContextImpl nsContext) throws IOException, SAXException, XMLStreamException;

    /**

     * Called at the very end. This is the last method to be invoked.

     *

     * @param fragment

     *      false if we are writing the whole document.

     */

    public void endDocument(boolean fragment) throws IOException, SAXException, XMLStreamException;

    /**

     * Writes a start tag.

     *

     * <p>

     * At this point {@link NamespaceContextImpl} holds namespace declarations needed for this

     * new element.

     *

     * <p>

     * This method is used for writing tags that are indexed.

     */

    public void beginStartTag(Name name) throws IOException, XMLStreamException;

    public void beginStartTag(int prefix, String localName) throws IOException, XMLStreamException;

    public void attribute( Name name, String value ) throws IOException, XMLStreamException;

    /**

     * @param prefix

     *      -1 if this attribute does not have a prefix

     *      (this handling differs from that of elements.)

     */

    public void attribute( int prefix, String localName, String value ) throws IOException, XMLStreamException;

    public void endStartTag() throws IOException, SAXException;

    public void endTag(Name name) throws IOException, SAXException, XMLStreamException;

    public void endTag(int prefix, String localName) throws IOException, SAXException, XMLStreamException;

    /**

     * Writes XML text with character escaping, if necessary.

     *

     * @param value

     *      this string can contain characters that might need escaping

     *      (such as '&' or '>')

     * @param needsSeparatingWhitespace

     */

    public void text( String value, boolean needsSeparatingWhitespace ) throws IOException, SAXException, XMLStreamException;

    /**

     * Writes XML text with character escaping, if necessary.

     *

     * @param value

     *      this string can contain characters that might need escaping

     *      (such as '&' or '>')

     * @param needsSeparatingWhitespace

     */

    public void text( Pcdata value, boolean needsSeparatingWhitespace ) throws IOException, SAXException, XMLStreamException;

}