/* Woodstox XML processor
 *
 * Copyright (c) 2004- Tatu Saloranta, tatu.saloranta@iki.fi
 *
 * Licensed under the License specified in file LICENSE, included with
 * the source code.
 * You may not use this file except in compliance with the License.
 *
 * 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 com.ctc.wstx.sw;

import java.io.IOException;
import java.io.Writer;
import java.text.MessageFormat;

import javax.xml.namespace.NamespaceContext;
import javax.xml.namespace.QName;
import javax.xml.stream.Location;
import javax.xml.stream.XMLReporter;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamWriter;

// unfortunate dependencies to StAX events:
import javax.xml.stream.events.Characters;
import javax.xml.stream.events.StartElement;

import org.codehaus.stax2.DTDInfo;
import org.codehaus.stax2.XMLStreamLocation2;
import org.codehaus.stax2.XMLStreamReader2;
import org.codehaus.stax2.ri.Stax2WriterImpl;
import org.codehaus.stax2.validation.*;

import com.ctc.wstx.api.*;
import com.ctc.wstx.cfg.ErrorConsts;
import com.ctc.wstx.cfg.OutputConfigFlags;
import com.ctc.wstx.cfg.XmlConsts;
import com.ctc.wstx.exc.*;
import com.ctc.wstx.io.WstxInputLocation;
import com.ctc.wstx.sr.StreamReaderImpl;
import com.ctc.wstx.sr.AttributeCollector;
import com.ctc.wstx.sr.InputElementStack;
import com.ctc.wstx.util.DataUtil;
import com.ctc.wstx.util.StringUtil;

Base class for XMLStreamWriter implementations Woodstox has. Contains partial stream writer implementation, plus utility methods shared by concrete implementation classes. Main reason for such abstract base class is to allow other parts of Woodstox core to refer to any of stream writer implementations in general way. /**
 * Base class for {@link XMLStreamWriter} implementations Woodstox has.
 * Contains partial stream writer implementation, plus utility methods
 * shared by concrete implementation classes. Main reason for such
 * abstract base class is to allow other parts of Woodstox core to refer
 * to any of stream writer implementations in general way.
 */
public abstract class BaseStreamWriter
    extends Stax2WriterImpl
    implements ValidationContext, OutputConfigFlags
{
    protected final static int STATE_PROLOG = 1;
    protected final static int STATE_TREE = 2;
    protected final static int STATE_EPILOG = 3;

    protected final static char CHAR_SPACE = ' ';

    
This constant defines minimum length of a String, for which it
is beneficial to do an intermediate copy (using String.getChars()),
and iterate over intermediate array, instead of iterating using
String.charAt(). Former is generally faster for longer Strings, but
has some overhead for shorter Strings. Tests indicate that the
threshold is somewhere between 8 and 16 characters, at least on
x86 platform.
/**
     * This constant defines minimum length of a String, for which it
     * is beneficial to do an intermediate copy (using String.getChars()),
     * and iterate over intermediate array, instead of iterating using
     * String.charAt(). Former is generally faster for longer Strings, but
     * has some overhead for shorter Strings. Tests indicate that the
     * threshold is somewhere between 8 and 16 characters, at least on
     * x86 platform.
     */
    protected final static int MIN_ARRAYCOPY = 12;

    protected final static int ATTR_MIN_ARRAYCOPY = 12;

    protected final static int DEFAULT_COPYBUFFER_LEN = 512;

    /*
    ///////////////////////////////////////////////////////////
    // Output objects
    ///////////////////////////////////////////////////////////
     */

    
Actual physical writer to output serialized XML content to
/**
     * Actual physical writer to output serialized XML content to
     */
    protected final XmlWriter mWriter;
    
    
Intermediate buffer into which characters of a String can be
copied, in cases where such a copy followed by array access
is faster than calling String.charAt() (which
perhaps surprisingly is often case, and especially significant
for longer buffers).
/**
     * Intermediate buffer into which characters of a String can be
     * copied, in cases where such a copy followed by array access
     * is faster than calling <code>String.charAt()</code> (which
     * perhaps surprisingly is often case, and especially significant
     * for longer buffers).
     */
    protected char[] mCopyBuffer = null;

    /*
    ///////////////////////////////////////////////////////////
    // Per-factory configuration (options, features)
    ///////////////////////////////////////////////////////////
     */

    protected final WriterConfig mConfig;

    // // // Specialized configuration flags, extracted from config flags:

    protected final boolean mCfgCDataAsText;
    protected final boolean mCfgCopyDefaultAttrs;
    protected final boolean mCfgAutomaticEmptyElems;

    // NOTE: can not be final, may be enabled when schema (etc) validation enabled

    protected boolean mCheckStructure;
    protected boolean mCheckAttrs;

    /*
    ///////////////////////////////////////////////////////////
    // Per-writer configuration
    ///////////////////////////////////////////////////////////
     */

    
Encoding to use; may be passed from the factory (when a method that defines encoding is used), updated by a call to writeStartDocument, or null if neither. Is passed to the escaping writer factory to allow escaping writers to do additional escaping if necessary (like encapsulating non-ascii chars in a doc encoded usig ascii). /**
     * Encoding to use; may be passed from the factory (when
     * a method that defines encoding is used), updated by
     * a call to {@link #writeStartDocument}, or null if
     * neither. Is passed to the escaping writer factory to
     * allow escaping writers to do additional escaping if
     * necessary (like encapsulating non-ascii chars in a doc
     * encoded usig ascii).
     */
    protected String mEncoding;

    
Optional validator to use for validating output against
one or more schemas, and/or for safe pretty-printing (indentation).
/**
     * Optional validator to use for validating output against
     * one or more schemas, and/or for safe pretty-printing (indentation).
     */
    protected XMLValidator mValidator = null;
    
    
Since XML 1.1 has some differences to 1.0, we need to keep a flag
to indicate if we were to output XML 1.1 document.
/**
     * Since XML 1.1 has some differences to 1.0, we need to keep a flag
     * to indicate if we were to output XML 1.1 document.
     */
    protected boolean mXml11 = false;

    
Custom validation problem handler, if any.
/**
     * Custom validation problem handler, if any.
     */
    protected ValidationProblemHandler mVldProbHandler = null;

    /*
    ////////////////////////////////////////////////////
    // State information
    ////////////////////////////////////////////////////
     */

    protected int mState = STATE_PROLOG;

    
Flag that is set to true first time something has been output.
Generally needed to keep track of whether XML declaration
(START_DOCUMENT) can be output or not.
/**
     * Flag that is set to true first time something has been output.
     * Generally needed to keep track of whether XML declaration
     * (START_DOCUMENT) can be output or not.
     */
    protected boolean mAnyOutput = false;

    
Flag that is set during time that a start element is "open", ie.
START_ELEMENT has been output (and possibly zero or more name
space declarations and attributes), before other main-level
constructs have been output.
/**
     * Flag that is set during time that a start element is "open", ie.
     * START_ELEMENT has been output (and possibly zero or more name
     * space declarations and attributes), before other main-level
     * constructs have been output.
     */
    protected boolean mStartElementOpen = false;

    
Flag that indicates that current element is an empty element (one
that is explicitly defined as one, by calling a method -- NOT one
that just happens to be empty).
This is needed to know what to do when next non-ns/attr node
is output; normally a new context is opened, but for empty
elements not.
/**
     * Flag that indicates that current element is an empty element (one
     * that is explicitly defined as one, by calling a method -- NOT one
     * that just happens to be empty).
     * This is needed to know what to do when next non-ns/attr node
     * is output; normally a new context is opened, but for empty
     * elements not.
     */
    protected boolean mEmptyElement = false;

    
State value used with validation, to track types of content
that is allowed at this point in output stream. Only used if
validation is enabled: if so, value is determined via validation
callbacks.
/**
     * State value used with validation, to track types of content
     * that is allowed at this point in output stream. Only used if
     * validation is enabled: if so, value is determined via validation
     * callbacks.
     */
    protected int mVldContent = XMLValidator.CONTENT_ALLOW_ANY_TEXT;

    
Value passed as the expected root element, when using the multiple argument writeDTD method. Will be used in structurally validating mode (and in dtd-validating mode, since that automatically enables structural validation as well, to pre-filter well-formedness errors that validators might have trouble dealing with). /**
     * Value passed as the expected root element, when using the multiple
     * argument {@link #writeDTD} method. Will be used in structurally
     * validating mode (and in dtd-validating mode, since that automatically
     * enables structural validation as well, to pre-filter well-formedness
     * errors that validators might have trouble dealing with).
     */
    protected String mDtdRootElem = null;
    
    protected boolean mReturnNullForDefaultNamespace;

    /*
    ////////////////////////////////////////////////////
    // Life-cycle
    ////////////////////////////////////////////////////
     */

    protected BaseStreamWriter(XmlWriter xw, String enc, WriterConfig cfg)
    {
        mWriter = xw;
        mEncoding = enc;
        mConfig = cfg;

        int flags = cfg.getConfigFlags();

        mCheckStructure = (flags & OutputConfigFlags.CFG_VALIDATE_STRUCTURE) != 0;
        mCheckAttrs = (flags & OutputConfigFlags.CFG_VALIDATE_ATTR) != 0;

        mCfgAutomaticEmptyElems = (flags & OutputConfigFlags.CFG_AUTOMATIC_EMPTY_ELEMENTS) != 0;
        mCfgCDataAsText = (flags & OutputConfigFlags.CFG_OUTPUT_CDATA_AS_TEXT) != 0;
        mCfgCopyDefaultAttrs = (flags & OutputConfigFlags.CFG_COPY_DEFAULT_ATTRS) != 0;
        
        mReturnNullForDefaultNamespace = mConfig.returnNullForDefaultNamespace();
    }

    /*
    ///////////////////////////////////////////////////////////
    // XMLStreamWriter API
    ///////////////////////////////////////////////////////////
     */

    @Override
    public void close()
        throws XMLStreamException
    {
        /* 19-Jul-2004, TSa: Hmmh. Let's actually close all still open
         *    elements, starting with currently open start (-> empty)
         *    element, if one exists, and then closing scopes by adding
         *    matching end elements.
         */
        _finishDocument(false);
    }

    @Override
    public void flush()
        throws XMLStreamException
    {
        /* Note: there have been changes to exact scope of flushing
         * (with Woodstox versions 2.x and 3.x); but the current 
         * one of just flushing the underlying OutputStream or Writer
         * should be the interpretation compatible with the Stax specs.
         */
        try {
            mWriter.flush();
        } catch (IOException ie) {
            throw new WstxIOException(ie);
        }
    }

    @Override
    public abstract NamespaceContext getNamespaceContext();

    @Override
    public abstract String getPrefix(String uri);

    @Override
    public Object getProperty(String name)
    {
        /* These properties just exist for interoperability with
         * toolkits that were designed to work with Sun's parser (which
         * introduced properties)
         */
        if (name.equals(WstxOutputProperties.P_OUTPUT_UNDERLYING_STREAM)) {
            return mWriter.getOutputStream();
        }
        if (name.equals(WstxOutputProperties.P_OUTPUT_UNDERLYING_WRITER)) {
            return mWriter.getWriter();
        }
        return mConfig.getProperty(name);
    }

    @Override
    public abstract void setDefaultNamespace(String uri)
        throws XMLStreamException;

    @Override
    public abstract void setNamespaceContext(NamespaceContext context)
        throws XMLStreamException;

    @Override
    public abstract void setPrefix(String prefix, String uri)
        throws XMLStreamException;

    @Override
    public abstract void writeAttribute(String localName, String value)
        throws XMLStreamException;
    
    @Override
    public abstract void writeAttribute(String nsURI, String localName,
                                        String value)
        throws XMLStreamException;

    @Override
    public abstract void writeAttribute(String prefix, String nsURI,
                                        String localName, String value)
        throws XMLStreamException;

    @Override
    public void writeCData(String data)
        throws XMLStreamException
    {
        // 02-Dec-2004, TSa: Maybe the writer is to "re-direct" these
        //   writes as normal text? (sometimes useful to deal with broken
        //   XML parsers, for example)
        if (mCfgCDataAsText) {
            writeCharacters(data);
            return;
        }

        mAnyOutput = true;
        // Need to finish an open start element?
        if (mStartElementOpen) {
            closeStartElement(mEmptyElement);
        }
        verifyWriteCData();
        if (mVldContent == XMLValidator.CONTENT_ALLOW_VALIDATABLE_TEXT
            && mValidator != null) {
            // Last arg is false, since we do not know if more text
            // may be added with additional calls
            mValidator.validateText(data, false);
        }
        int ix;
        try {
            ix = mWriter.writeCData(data);
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }
        if (ix >= 0) { // unfixable problems?
            reportNwfContent(ErrorConsts.WERR_CDATA_CONTENT, DataUtil.Integer(ix));
        }
    }

    @Override
    public void writeCharacters(char[] text, int start, int len)
        throws XMLStreamException
    {
        mAnyOutput = true;
        // Need to finish an open start element?
        if (mStartElementOpen) {
            closeStartElement(mEmptyElement);
        }

        // Not legal outside main element tree, except if it's all white space
        if (mCheckStructure) {
            if (inPrologOrEpilog()) {
                if (!StringUtil.isAllWhitespace(text, start, len)) {
                    reportNwfStructure(ErrorConsts.WERR_PROLOG_NONWS_TEXT);
                }
            }
        }
        // 08-Dec-2005, TSa: validator-based validation?
        if (mVldContent <= XMLValidator.CONTENT_ALLOW_WS) {
            if (mVldContent == XMLValidator.CONTENT_ALLOW_NONE) { // never ok
                reportInvalidContent(CHARACTERS);
            } else { // all-ws is ok...
                if (!StringUtil.isAllWhitespace(text, start, len)) {
                    reportInvalidContent(CHARACTERS);
                }
            }
        } else if (mVldContent == XMLValidator.CONTENT_ALLOW_VALIDATABLE_TEXT) {
            if (mValidator != null) {
                // Last arg is false, since we do not know if more text
                // may be added with additional calls
                mValidator.validateText(text, start, start + len, false);
            }
        }

        if (len > 0) { // minor optimization
            try {
                // 21-Jun-2006, TSa: Fixing [WSTX-59]: no quoting can be done
                //   outside of element tree.
                if (inPrologOrEpilog()) {
                    mWriter.writeRaw(text, start, len);
                } else {
                    mWriter.writeCharacters(text, start, len);
                }
            } catch (IOException ioe) {
                throw new WstxIOException(ioe);
            }
        }
    }

    @Override
    public void writeCharacters(String text)
        throws XMLStreamException
    {
        mAnyOutput = true;
        // Need to finish an open start element?
        if (mStartElementOpen) {
            closeStartElement(mEmptyElement);
        }

        // Need to validate structure?
        if (mCheckStructure) {
            // Not valid in prolog/epilog, except if it's all white space:
            if (inPrologOrEpilog()) {
                if (!StringUtil.isAllWhitespace(text)) {
                    reportNwfStructure(ErrorConsts.WERR_PROLOG_NONWS_TEXT);
                }
            }
        }

        /* 08-Dec-2005, TSa: validator-based validation?
         *   Note: although it'd be good to check validity first, we
         *   do not know allowed textual content before actually writing
         *   pending start element (if any)... so can't call this earlier
         */
        if (mVldContent <= XMLValidator.CONTENT_ALLOW_WS) {
            if (mVldContent == XMLValidator.CONTENT_ALLOW_NONE) { // never ok
                reportInvalidContent(CHARACTERS);
            } else { // all-ws is ok...
                if (!StringUtil.isAllWhitespace(text)) {
                    reportInvalidContent(CHARACTERS);
                }
            }
        } else if (mVldContent == XMLValidator.CONTENT_ALLOW_VALIDATABLE_TEXT) {
            if (mValidator != null) {
                /* Last arg is false, since we do not know if more text
                 * may be added with additional calls
                 */
                mValidator.validateText(text, false);
            }
        }

        // Ok, let's just write it out
        /* 21-Jun-2006, TSa: Fixing [WSTX-59]: no quoting can be done
         *   outside of element tree.
         */
        if (inPrologOrEpilog()) {
            try {
                mWriter.writeRaw(text);
            } catch (IOException ioe) {
                throw new WstxIOException(ioe);
            }
            return;
        }

        /* Now, would it pay off to make an intermediate copy?
         * String.getChars (which uses System.arraycopy()) is
         * very fast compared to access via String.charAt.
         */
        int len = text.length();
        if (len >= MIN_ARRAYCOPY) {
            char[] buf = getCopyBuffer();

            int offset = 0;
            while (len > 0) {
                int thisLen = (len > buf.length) ? buf.length : len;
                text.getChars(offset, offset+thisLen, buf, 0);
                try {
                    mWriter.writeCharacters(buf, 0, thisLen);
                } catch (IOException ioe) {
                    throw new WstxIOException(ioe);
                }
                offset += thisLen;
                len -= thisLen;
            }
        } else { // nope, let's just access String using charAt().
            try {
                mWriter.writeCharacters(text);
            } catch (IOException ioe) {
                throw new WstxIOException(ioe);
            }
        }
    }

    @Override
    public void writeComment(String data)
        throws XMLStreamException
    {
        mAnyOutput = true;
        // Need to finish an open start element?
        if (mStartElementOpen) {
            closeStartElement(mEmptyElement);
        }

        // 08-Dec-2005, TSa: validator-based validation?
        if (mVldContent == XMLValidator.CONTENT_ALLOW_NONE) {
            reportInvalidContent(COMMENT);
        }

        /* No structural validation needed per se, for comments; they are
         * allowed anywhere in XML content. However, content may need to
         * be checked (by XmlWriter)
         */
        int ix;
        try {
            ix = mWriter.writeComment(data);
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }

        if (ix >= 0) {
            reportNwfContent(ErrorConsts.WERR_COMMENT_CONTENT, DataUtil.Integer(ix));
        }
    }

    @Override
    public abstract void writeDefaultNamespace(String nsURI)
        throws XMLStreamException;

    @Override
    public void writeDTD(String dtd)
        throws XMLStreamException
    {
        verifyWriteDTD();
        mDtdRootElem = ""; // marker to verify only one is output
        try {
            mWriter.writeDTD(dtd);
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }

        /* 20-Dec-2005, TSa: Should we try to decipher what was actually
         *   written, for validation?
         */
    }

    @Override
    public abstract void writeEmptyElement(String localName)
        throws XMLStreamException;

    @Override
    public abstract void writeEmptyElement(String nsURI, String localName)
        throws XMLStreamException;

    @Override
    public abstract void writeEmptyElement(String prefix, String localName, String nsURI)
        throws XMLStreamException;

    @Override
    public void writeEndDocument() throws XMLStreamException
    {
        _finishDocument(false);
    }

    @Override
    public abstract void writeEndElement() throws XMLStreamException;

    @Override
    public void writeEntityRef(String name)
        throws XMLStreamException
    {
        mAnyOutput = true;
        // Need to finish an open start element?
        if (mStartElementOpen) {
            closeStartElement(mEmptyElement);
        }

        // Structurally, need to check we are not in prolog/epilog.
        if (mCheckStructure) {
            if (inPrologOrEpilog()) {
                reportNwfStructure("Trying to output an entity reference outside main element tree (in prolog or epilog)");
            }
        }
        // 08-Dec-2005, TSa: validator-based validation?
        if (mVldContent == XMLValidator.CONTENT_ALLOW_NONE) {
            /* May be char entity, general entity; whatever it is it's
             * invalid!
             */
            reportInvalidContent(ENTITY_REFERENCE);
        }

        //if (mValidator != null) {
            /* !!! 11-Dec-2005, TSa: Should be able to use DTD based validators
             *    to check if entity has been declared...
             */
        //}

        try {
            mWriter.writeEntityReference(name);
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }
    }

    @Override
    public abstract void writeNamespace(String prefix, String nsURI)
        throws XMLStreamException;

    @Override
    public void writeProcessingInstruction(String target)
        throws XMLStreamException
    {
        writeProcessingInstruction(target, null);
    }

    @Override
    public void writeProcessingInstruction(String target, String data)
        throws XMLStreamException
    {
        mAnyOutput = true;
        // Need to finish an open start element?
        if (mStartElementOpen) {
            closeStartElement(mEmptyElement);
        }

        // Structurally, PIs are always ok (content might not be)
        // 08-Dec-2005, TSa: validator-based validation?
        if (mVldContent == XMLValidator.CONTENT_ALLOW_NONE) {
            reportInvalidContent(PROCESSING_INSTRUCTION);
        }
        int ix;
        try {
            ix = mWriter.writePI(target, data);
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }
        if (ix >= 0) {
            throw new XMLStreamException("Illegal input: processing instruction content has embedded '?>' in it (index "+ix+")");
        }
    }

    @Override
    public void writeStartDocument()
        throws XMLStreamException
    {
        /* 03-Feb-2005, TSa: As per StAX 1.0 specs, version should
         *   be "1.0", and encoding "utf-8" (yes, lower case... it's
         *   wrong, but specs mandate it)
         */
        /* 11-Jan-2006, TSa: Let's actually rather use whatever was passed
         *   in, if anything; only if none then default to something else.
         *   Plus, what the heck; let's use properly capitalized value
         *   too (and ignore faulty def in stax specs).
         */
        if (mEncoding == null) {
            mEncoding = WstxOutputProperties.DEFAULT_OUTPUT_ENCODING;
        }
        writeStartDocument(mEncoding, WstxOutputProperties.DEFAULT_XML_VERSION);
    }

    @Override
    public void writeStartDocument(String version)
        throws XMLStreamException
    {
        writeStartDocument(mEncoding, version);
    }

    @Override
    public void writeStartDocument(String encoding, String version)
        throws XMLStreamException
    {
        doWriteStartDocument(version, encoding, null);
    }

    protected void doWriteStartDocument(String version, String encoding,
                                        String standAlone)
        throws XMLStreamException
    {
        /* Not legal to output XML declaration if there has been ANY
         * output prior... that is, if we validate the structure.
         */
        if (mCheckStructure) {
            if (mAnyOutput) {
                reportNwfStructure("Can not output XML declaration, after other output has already been done.");
            }
        }

        mAnyOutput = true;

        if (mConfig.willValidateContent()) {
            // !!! 06-May-2004, TSa: Should validate encoding?
            /*if (encoding != null) {
            }*/
            if (version != null && version.length() > 0) {
                if (!(version.equals(XmlConsts.XML_V_10_STR)
                      || version.equals(XmlConsts.XML_V_11_STR))) {
                    reportNwfContent("Illegal version argument ('"+version
                                     +"'); should only use '"+XmlConsts.XML_V_10_STR
                                    +"' or '"+XmlConsts.XML_V_11_STR+"'");
                }
            }
        }

        if (version == null || version.length() == 0) {
            version = WstxOutputProperties.DEFAULT_XML_VERSION;
        }

        /* 04-Feb-2006, TSa: Need to know if we are writing XML 1.1
         *   document...
         */
        mXml11 = XmlConsts.XML_V_11_STR.equals(version);
        if (mXml11) {
            mWriter.enableXml11();
        }

        if (encoding != null && encoding.length() > 0) {
            /* 03-May-2005, TSa: But what about conflicting encoding? Let's
             *   only update encoding, if it wasn't set.
             */
            if (mEncoding == null || mEncoding.length() == 0) {
                mEncoding = encoding;
            }
        }
        try {
            mWriter.writeXmlDeclaration(version, encoding, standAlone);
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }
    }

    @Override
    public abstract void writeStartElement(String localName)
        throws XMLStreamException;

    @Override
    public abstract void writeStartElement(String nsURI, String localName)
        throws XMLStreamException;

    @Override
    public abstract void writeStartElement(String prefix, String localName,
                                           String nsURI)
        throws XMLStreamException;
    
    /*
    ///////////////////////////////////////////////////////////
    // XMLStreamWriter2 methods (StAX2)
    ///////////////////////////////////////////////////////////
     */

    
Method that essentially copies event that the specified reader has
just read.
Params:
sr – Stream reader to use for accessing event to copy
preserveEventData – If true, writer is not allowed to change
  the state of the reader (so that all the data associated with the
  current event has to be preserved); if false, writer is allowed
  to use methods that may cause some data to be discarded. Setting
  this to false may improve the performance, since it may allow
  full no-copy streaming of data, especially textual contents./**
     * Method that essentially copies event that the specified reader has
     * just read.
     *
     * @param sr Stream reader to use for accessing event to copy
     * @param preserveEventData If true, writer is not allowed to change
     *   the state of the reader (so that all the data associated with the
     *   current event has to be preserved); if false, writer is allowed
     *   to use methods that may cause some data to be discarded. Setting
     *   this to false may improve the performance, since it may allow
     *   full no-copy streaming of data, especially textual contents.
     */
    @Override
    public void copyEventFromReader(XMLStreamReader2 sr, boolean preserveEventData)
        throws XMLStreamException
    {
        try {
            switch (sr.getEventType()) {
            case START_DOCUMENT:
                {
                    String version = sr.getVersion();
                    // No real declaration? If so, we don't want to output anything, to replicate
                    // as closely as possible the source document
                    if (version == null || version.length() == 0) {
                        ; // no output if no real input
                    } else {
                        if (sr.standaloneSet()) {
                            writeStartDocument(sr.getVersion(),
                                               sr.getCharacterEncodingScheme(),
                                               sr.isStandalone());
                        } else {
                            writeStartDocument(sr.getCharacterEncodingScheme(),
                                               sr.getVersion());
                        }
                    }
                }
                return;
                
            case END_DOCUMENT:
                writeEndDocument();
                return;
                
                // Element start/end events:
            case START_ELEMENT:
                if (sr instanceof StreamReaderImpl) {
                    StreamReaderImpl impl = (StreamReaderImpl) sr;
                    copyStartElement(impl.getInputElementStack(), impl.getAttributeCollector());
                } else { // otherwise impl from Stax ref. impl (Stax2WriterImpl) has to do:
                    super.copyStartElement(sr);
                }
                return;

            case END_ELEMENT:
                writeEndElement();
                return;
                
            case SPACE:
                {
                    mAnyOutput = true;
                    // Need to finish an open start element?
                    if (mStartElementOpen) {
                        closeStartElement(mEmptyElement);
                    }
                    // No need to write as chars, should be pure space (caller should
                    // have verified); also, no escaping necessary.

                    // 28-Mar-2017, tatu: Various optimization do not work well when validation so:
                    if (mValidator != null) {
                        writeSpace(sr.getText());
                    } else {
                        sr.getText(wrapAsRawWriter(), preserveEventData);
                    }
                }
                return;

            case CDATA:

                // First; is this to be changed to 'normal' text output?
                // 28-Mar-2017, tatu: Various optimization do not work well when validation so:
                if (mValidator != null) {
                    writeCData(sr.getText());
                    return;
                }
                if (!mCfgCDataAsText) {
                    mAnyOutput = true;
                    // Need to finish an open start element?
                    if (mStartElementOpen) {
                        closeStartElement(mEmptyElement);
                    }

                    // Not legal outside main element tree:
                    if (mCheckStructure) {
                        if (inPrologOrEpilog()) {
                            reportNwfStructure(ErrorConsts.WERR_PROLOG_CDATA);
                        }
                    }
                    // Note: no need to check content, since reader is assumed
                    // to have verified it to be valid XML.
                    mWriter.writeCDataStart();
                    sr.getText(wrapAsRawWriter(), preserveEventData);
                    mWriter.writeCDataEnd();
                    return;
                }
                // fall down if it is to be converted...

            case CHARACTERS:

                // 28-Mar-2017, tatu: Various optimization do not work well when validation so:
                if (mValidator != null) {
                    writeCharacters(sr.getText());
                } else  {
                    // Let's just assume content is fine... not 100% reliably
                    // true, but usually is (not true if input had a root
                    // element surrounding text, but omitted for output)
                    mAnyOutput = true;
                    // Need to finish an open start element?
                    if (mStartElementOpen) {
                        closeStartElement(mEmptyElement);
                    }
                    sr.getText(wrapAsTextWriter(), preserveEventData);
                }
                return;
                
            case COMMENT:
                {
                    mAnyOutput = true;
                    if (mStartElementOpen) {
                        closeStartElement(mEmptyElement);
                    }
                    // No need to check for content (embedded '--'); reader
                    // is assumed to have verified it's ok (otherwise should
                    // have thrown an exception for non-well-formed XML)
                    mWriter.writeCommentStart();
                    sr.getText(wrapAsRawWriter(), preserveEventData);
                    mWriter.writeCommentEnd();
                }
                return;

            case PROCESSING_INSTRUCTION:
                {
                    mWriter.writePIStart(sr.getPITarget(), true);
                    sr.getText(wrapAsRawWriter(), preserveEventData);
                    mWriter.writePIEnd();
                }
                return;
                
            case DTD:
                {
                    DTDInfo info = sr.getDTDInfo();
                    if (info == null) {
                        // Hmmmh. It is legal for this to happen, for non-DTD-aware
                        // readers. But what is the right thing to do here?
                        throwOutputError("Current state DOCTYPE, but not DTDInfo Object returned -- reader doesn't support DTDs?");
                    }
                    // Could optimize this a bit (stream the int. subset possible),
                    // but it's never going to occur more than once per document,
                    // so it's probably not much of a bottleneck, ever
                    writeDTD(info);
                }
                return;
                
            case ENTITY_REFERENCE:
                writeEntityRef(sr.getLocalName());
                return;

            case ATTRIBUTE:
            case NAMESPACE:
            case ENTITY_DECLARATION:
            case NOTATION_DECLARATION:
                // Let's just fall back to throw the exception
            }
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }
        throw new XMLStreamException("Unrecognized event type ("
                +sr.getEventType()+"); not sure how to copy");
    }

    /*
    ///////////////////////////////////////////////////////////
    // StAX2, output handling
    ///////////////////////////////////////////////////////////
     */

    @Override
    public void closeCompletely()
        throws XMLStreamException
    {
        _finishDocument(true);
    }

    /*
    ///////////////////////////////////////////////////////////
    // StAX2, config
    ///////////////////////////////////////////////////////////
     */

    // NOTE: getProperty() defined in Stax 1.0 interface

    @Override
    public boolean isPropertySupported(String name) {
        // !!! TBI: not all these properties are really supported
        return mConfig.isPropertySupported(name);
    }

    
Params:
name – Name of the property to set
value – Value to set property to.
Returns:
True, if the specified property was succesfully
   set to specified value; false if its value was not changed/**
     * @param name Name of the property to set
     * @param value Value to set property to.
     *
     * @return True, if the specified property was <b>succesfully</b>
     *    set to specified value; false if its value was not changed
     */
    @Override
    public boolean setProperty(String name, Object value)
    {
        /* Note: can not call local method, since it'll return false for
         * recognized but non-mutable properties
         */
        return mConfig.setProperty(name, value);
    }

    @Override
    public XMLValidator validateAgainst(XMLValidationSchema schema)
        throws XMLStreamException
    {
        XMLValidator vld = schema.createValidator(this);

        if (mValidator == null) {
            /* Need to enable other validation modes? Structural validation
             * should always be done when we have other validators as well,
             * as well as attribute uniqueness checks.
             */
            mCheckStructure = true;
            mCheckAttrs = true;
            mValidator = vld;
        } else {
            mValidator = new ValidatorPair(mValidator, vld);
        }
        return vld;
    }

    @Override
    public XMLValidator stopValidatingAgainst(XMLValidationSchema schema)
        throws XMLStreamException
    {
        XMLValidator[] results = new XMLValidator[2];
        XMLValidator found = null;
        if (ValidatorPair.removeValidator(mValidator, schema, results)) { // found
            found = results[0];
            mValidator = results[1];
            found.validationCompleted(false);
            if (mValidator == null) {
                resetValidationFlags();
            }
        }
        return found;
    }

    @Override
    public XMLValidator stopValidatingAgainst(XMLValidator validator)
        throws XMLStreamException
    {
        XMLValidator[] results = new XMLValidator[2];
        XMLValidator found = null;
        if (ValidatorPair.removeValidator(mValidator, validator, results)) { // found
            found = results[0];
            mValidator = results[1];
            found.validationCompleted(false);
            if (mValidator == null) {
                resetValidationFlags();
            }
        }
        return found;
    }

    @Override
    public ValidationProblemHandler setValidationProblemHandler(ValidationProblemHandler h)
    {
        ValidationProblemHandler oldH = mVldProbHandler;
        mVldProbHandler = h;
        return oldH;
    }

    private void resetValidationFlags()
    {
        int flags = mConfig.getConfigFlags();
        mCheckStructure = (flags & CFG_VALIDATE_STRUCTURE) != 0;
        mCheckAttrs = (flags & CFG_VALIDATE_ATTR) != 0;
    }

    /*
    ///////////////////////////////////////////////////////////
    // StAX2, other accessors, mutators
    ///////////////////////////////////////////////////////////
     */

    @Override
    public XMLStreamLocation2 getLocation()
    {
        return new WstxInputLocation(null, // no parent
        		null, (String) null, // pub/sys ids not yet known
        		mWriter.getAbsOffset(),
        		mWriter.getRow(), mWriter.getColumn());
    }

    @Override
    public String getEncoding() {
        return mEncoding;
    }

    /*
    ///////////////////////////////////////////////////////////
    // StAX2, output methods
    ///////////////////////////////////////////////////////////
     */

    @Override
    public void writeCData(char[] cbuf, int start, int len)
        throws XMLStreamException
    {
        /* 02-Dec-2004, TSa: Maybe the writer is to "re-direct" these
         *   writes as normal text? (sometimes useful to deal with broken
         *   XML parsers, for example)
         */
        if (mCfgCDataAsText) {
            writeCharacters(cbuf, start, len);
            return;
        }

        mAnyOutput = true;
        // Need to finish an open start element?
        if (mStartElementOpen) {
            closeStartElement(mEmptyElement);
        }
        verifyWriteCData();
        if (mVldContent == XMLValidator.CONTENT_ALLOW_VALIDATABLE_TEXT
            && mValidator != null) {
            /* Last arg is false, since we do not know if more text
             * may be added with additional calls
             */
            mValidator.validateText(cbuf, start, start + len, false);
        }
        int ix;
        try {
            ix = mWriter.writeCData(cbuf, start, len);
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }
        if (ix >= 0) { // problems that could not to be fixed?
            throwOutputError(ErrorConsts.WERR_CDATA_CONTENT, DataUtil.Integer(ix));
        }
    }

    public void writeDTD(DTDInfo info)
        throws XMLStreamException
    {
        writeDTD(info.getDTDRootName(), info.getDTDSystemId(),
                 info.getDTDPublicId(), info.getDTDInternalSubset());
    }

    @Override
    public void writeDTD(String rootName, String systemId, String publicId,
                         String internalSubset)
        throws XMLStreamException
    {
        verifyWriteDTD();
        mDtdRootElem = rootName;
        try {
            mWriter.writeDTD(rootName, systemId, publicId, internalSubset);
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }
    }

    @Override
    public abstract void writeFullEndElement() throws XMLStreamException;

    @Override
    public void writeStartDocument(String version, String encoding,
                                   boolean standAlone)
        throws XMLStreamException
    {
        doWriteStartDocument(version, encoding, standAlone ? "yes" : "no");
    }

    @Override
    public void writeRaw(String text)
        throws XMLStreamException
    {
        mAnyOutput = true;
        if (mStartElementOpen) {
            closeStartElement(mEmptyElement);
        }
        try {
            mWriter.writeRaw(text, 0, text.length());
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }
    }

    @Override
    public void writeRaw(String text, int start, int offset)
        throws XMLStreamException
    {
        mAnyOutput = true;
        if (mStartElementOpen) {
            closeStartElement(mEmptyElement);
        }
        try {
            mWriter.writeRaw(text, start, offset);
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }
    }

    @Override
    public void writeRaw(char[] text, int start, int offset)
        throws XMLStreamException
    {
        mAnyOutput = true;
        if (mStartElementOpen) {
            closeStartElement(mEmptyElement);
        }
        try {
            mWriter.writeRaw(text, start, offset);
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }
    }

    @Override
    public void writeSpace(String text)
        throws XMLStreamException
    {
        /* For now, let's just use writeRaw(): otherwise would need
         * to add it to all backend writers:
         */
        writeRaw(text);
    }

    @Override
    public void writeSpace(char[] text, int offset, int length)
        throws XMLStreamException
    {
        // For now, let's just use writeRaw() (see above)
        writeRaw(text, offset, length);
    }

    /*
    ///////////////////////////////////////////////////////////
    // ValidationContext interface (StAX2, validation)
    ///////////////////////////////////////////////////////////
     */

    @Override
    public String getXmlVersion() {
        return mXml11 ? XmlConsts.XML_V_11_STR : XmlConsts.XML_V_10_STR;
    }

    @Override
    public abstract QName getCurrentElementName();

    @Override
    public abstract String getNamespaceURI(String prefix);

    
As of now, there is no way to specify the base URI. Could be improved
in future, if xml:base is supported.
/**
     * As of now, there is no way to specify the base URI. Could be improved
     * in future, if xml:base is supported.
     */
    @Override
    public String getBaseUri() {
        return null;
    }

    @Override
    public Location getValidationLocation() {
        return getLocation();
    }

    @Override
    public void reportProblem(XMLValidationProblem prob)
        throws XMLStreamException
    {
        // Custom handler set? If so, it'll take care of it:
        if (mVldProbHandler != null) {
            mVldProbHandler.reportProblem(prob);
            return;
        }

        /* For now let's implement basic functionality: warnings get
         * reported via XMLReporter, errors and fatal errors result in
         * immediate exceptions.
         */
        /* 27-May-2008, TSa: [WSTX-153] Above is incorrect: as per Stax
         *   javadocs for XMLReporter, both warnings and non-fatal errors
         *   (which includes all validation errors) should be reported via
         *   XMLReporter interface, and only fatals should cause an
         *   immediate stream exception (by-passing reporter)
         */
        if (prob.getSeverity() > XMLValidationProblem.SEVERITY_ERROR) {
            throw WstxValidationException.create(prob);
        }
        XMLReporter rep = mConfig.getProblemReporter();
        if (rep != null) {
            doReportProblem(rep, prob);
        } else {
            /* If no reporter, regular non-fatal errors are to be reported
             * as exceptions as well, for backwards compatibility
             */
            if (prob.getSeverity() >= XMLValidationProblem.SEVERITY_ERROR) {
                throw WstxValidationException.create(prob);
            }
        }
    }

    
Adding default attribute values does not usually make sense on
output side, so the implementation is a NOP for now.
/**
     * Adding default attribute values does not usually make sense on
     * output side, so the implementation is a NOP for now.
     */
    @Override
    public int addDefaultAttribute(String localName, String uri, String prefix,
                                   String value)
    {
        // nothing to do, but to indicate we didn't add it...
        return -1;
    }

    // // // Notation/entity access: not (yet?) implemented

    @Override
    public boolean isNotationDeclared(String name) { return false; }

    @Override
    public boolean isUnparsedEntityDeclared(String name) { return false; }

    // // // Attribute access: not yet implemented:

    /* !!! TODO: Implement attribute access (iff validate-attributes
     *   enabled?
     */

    @Override
    public int getAttributeCount() { return 0; }

    @Override
    public String getAttributeLocalName(int index) { return null; }

    @Override
    public String getAttributeNamespace(int index) { return null; }

    @Override
    public String getAttributePrefix(int index) { return null; }

    @Override
    public String getAttributeValue(int index) { return null; }

    @Override
    public String getAttributeValue(String nsURI, String localName) {
        return null;
    }

    @Override
    public String getAttributeType(int index) {
        return "";
    }

    @Override
    public int findAttributeIndex(String nsURI, String localName) {
        return -1;
    }

    /*
    ///////////////////////////////////////////////////////////
    // Package methods (ie not part of public API)
    ///////////////////////////////////////////////////////////
     */

    
Method that can be called to get a wrapper instance that
can be used to essentially call the writeRaw
method via regular Writer interface.
/**
     * Method that can be called to get a wrapper instance that
     * can be used to essentially call the <code>writeRaw</code>
     * method via regular <code>Writer</code> interface.
     */
    public final Writer wrapAsRawWriter()
    {
        return mWriter.wrapAsRawWriter();
    }

    
Method that can be called to get a wrapper instance that
can be used to essentially call the writeCharacters
method via regular Writer interface.
/**
     * Method that can be called to get a wrapper instance that
     * can be used to essentially call the <code>writeCharacters</code>
     * method via regular <code>Writer</code> interface.
     */
    public final Writer wrapAsTextWriter()
    {
        return mWriter.wrapAsTextWriter();
    }

    
Method that is used by output classes to determine whether we
are in validating mode.

Note: current implementation of this method is not perfect; it
may be possible it can return true even if we are only using a DTD
to get some limited info, without validating?
/**
     * Method that is used by output classes to determine whether we
     * are in validating mode.
     *<p>
     * Note: current implementation of this method is not perfect; it
     * may be possible it can return true even if we are only using a DTD
     * to get some limited info, without validating?
     */
    protected boolean isValidating() {
        return (mValidator != null);
    }

    
Convenience method needed by XMLEventWriter implementation, to use when writing a start element, and possibly its attributes and namespace declarations. /**
     * Convenience method needed by {@link javax.xml.stream.XMLEventWriter}
     * implementation, to use when
     * writing a start element, and possibly its attributes and namespace
     * declarations.
     */
    public abstract void writeStartElement(StartElement elem)
        throws XMLStreamException;

    
Method called by XMLEventWriter (instead of the version that takes no argument), so that we can verify it does match the start element if necessary. /**
     * Method called by {@link javax.xml.stream.XMLEventWriter}
     * (instead of the version
     * that takes no argument), so that we can verify it does match the
     * start element if necessary.
     */
    public abstract void writeEndElement(QName name)
        throws XMLStreamException;

    
Method called by XMLEventWriter (instead of more generic text output methods), so that we can verify (if necessary) that this character output type is legal in this context. Specifically, it's not acceptable to add non-whitespace content outside root element (in prolog/epilog). 

Note: cut'n pasted from the main writeCharacters; not
good... but done to optimize white-space cases.
/**
     * Method called by {@link javax.xml.stream.XMLEventWriter}
     * (instead of more generic
     * text output methods), so that we can verify (if necessary) that
     * this character output type is legal in this context. Specifically,
     * it's not acceptable to add non-whitespace content outside root
     * element (in prolog/epilog).
     *<p>
     * Note: cut'n pasted from the main <code>writeCharacters</code>; not
     * good... but done to optimize white-space cases.
     */
    public void writeCharacters(Characters ch)
        throws XMLStreamException
    {
        // Need to finish an open start element?
        if (mStartElementOpen) {
            closeStartElement(mEmptyElement);
        }

        /* Not legal outside main element tree, except if it's all
         * white space
         */
        if (mCheckStructure) {
            if (inPrologOrEpilog()) {
                if (!ch.isIgnorableWhiteSpace() && !ch.isWhiteSpace()) {
                    reportNwfStructure(ErrorConsts.WERR_PROLOG_NONWS_TEXT);
                }
            }
        }

        if (mVldContent <= XMLValidator.CONTENT_ALLOW_WS) {
            if (mVldContent == XMLValidator.CONTENT_ALLOW_NONE) { // never ok
                reportInvalidContent(CHARACTERS);
            } else { // all-ws is ok...
                if (!ch.isIgnorableWhiteSpace() && !ch.isWhiteSpace()) {
                    reportInvalidContent(CHARACTERS);
                }
            }
        } else if (mVldContent == XMLValidator.CONTENT_ALLOW_VALIDATABLE_TEXT) {
            if (mValidator != null) {
                /* Last arg is false, since we do not know if more text
                 * may be added with additional calls
                 */
                mValidator.validateText(ch.getData(), false);
            }
        }

        // Ok, let's just write it out:
        try {
            mWriter.writeCharacters(ch.getData());
        } catch (IOException ioe) {
            throw new WstxIOException(ioe);
        }
    }
    
    
Method called to close an open start element, when another
main-level element (not namespace declaration or attribute)
is being output; except for end element which is handled differently.
/**
     * Method called to close an open start element, when another
     * main-level element (not namespace declaration or attribute)
     * is being output; except for end element which is handled differently.
     */
    protected abstract void closeStartElement(boolean emptyElem)
        throws XMLStreamException;

    protected final boolean inPrologOrEpilog() {
        return (mState != STATE_TREE);
    }

    
Params:
forceRealClose – If true, will force calling of close() on the
  underlying physical result (stream, writer). If false, will let
  XmlWriter decide whether to call close(); will be done if auto-closing
  enabled, but not otherwise./**
     * @param forceRealClose If true, will force calling of close() on the
     *   underlying physical result (stream, writer). If false, will let
     *   XmlWriter decide whether to call close(); will be done if auto-closing
     *   enabled, but not otherwise.
     */
    private final void _finishDocument(boolean forceRealClose)
        throws XMLStreamException
    {
        // Is tree still open?
        if (mState != STATE_EPILOG) {
            if (mCheckStructure  && mState == STATE_PROLOG) {
                reportNwfStructure("Trying to write END_DOCUMENT when document has no root (ie. trying to output empty document).");
            }
            // 20-Jul-2004, TSa: Need to close the open sub-tree, if it exists...
            // First, do we have an open start element?
            if (mStartElementOpen) {
                closeStartElement(mEmptyElement);
            }
            // Then, one by one, need to close open scopes:
            /* 17-Nov-2008, TSa: that is, if we are allowed to do it
             *   (see [WSTX-165])
             */
            if (mState != STATE_EPILOG && mConfig.automaticEndElementsEnabled()) {
                do {
                    writeEndElement();
                } while (mState != STATE_EPILOG);
            }
        }

        /* And finally, inform the underlying writer that it should flush
         * and release its buffers, and close components it uses if any.
         */
        char[] buf = mCopyBuffer;
        if (buf != null) {
            mCopyBuffer = null;
            mConfig.freeMediumCBuffer(buf);
        }
        try {
            mWriter.close(forceRealClose);
        } catch (IOException ie) {
            throw new WstxIOException(ie);
        }
    }

    
Implementation-dependant method called to fully copy START_ELEMENT
event that the passed-in stream reader points to
/**
     * Implementation-dependant method called to fully copy START_ELEMENT
     * event that the passed-in stream reader points to
     */
    public abstract void copyStartElement(InputElementStack elemStack,
                                          AttributeCollector attrCollector)
        throws IOException, XMLStreamException;

    
Method called before writing a QName via Typed Access API.
In namespace-repairing mode it should take appropriate actions
to ensure that the given namespace URI is bound to a namespace
and return whatever it maps to. In non-repairing work no additional
work is to be done and methods
Returns:
Prefix to use when writing out given QName as an element
  or attribute value/**
     * Method called before writing a QName via Typed Access API.
     * In namespace-repairing mode it should take appropriate actions
     * to ensure that the given namespace URI is bound to a namespace
     * and return whatever it maps to. In non-repairing work no additional
     * work is to be done and methods
     *
     * @return Prefix to use when writing out given QName as an element
     *   or attribute value
     */
    public abstract String validateQNamePrefix(QName name)
        throws XMLStreamException;

    /*
    ///////////////////////////////////////////////////////////
    // Package methods, validation
    ///////////////////////////////////////////////////////////
     */

    protected final void verifyWriteCData()
        throws XMLStreamException
    {
        // Not legal outside main element tree:
        if (mCheckStructure) {
            if (inPrologOrEpilog()) {
                reportNwfStructure(ErrorConsts.WERR_PROLOG_CDATA);
            }
        }
        // 08-Dec-2005, TSa: validator-based validation?
        if (mVldContent <= XMLValidator.CONTENT_ALLOW_WS) {
            // there's no ignorable white space CDATA...
            reportInvalidContent(CDATA);
        }
    }

    protected final void verifyWriteDTD()
        throws XMLStreamException
    {
        // 20-Nov-2004, TSa: can check that we are in prolog
        if (mCheckStructure) {
            if (mState != STATE_PROLOG) {
                throw new XMLStreamException("Can not write DOCTYPE declaration (DTD) when not in prolog any more (state "+mState+"; start element(s) written)");
            }
            // 20-Dec-2005, TSa: and that we only output one...
            if (mDtdRootElem != null) {
                throw new XMLStreamException("Trying to write multiple DOCTYPE declarations");
            }
        }
    }

    protected void verifyRootElement(String localName, String prefix)
        throws XMLStreamException
    {
        /* Note: this check is bit lame, due to DOCTYPE declaration (and DTD
         * in general) being namespace-ignorant...
         */
        if (isValidating()) {
            /* 17-Mar-2006, TSa: Ideally, this should be a validity
             *   problem?
             */
            if (mDtdRootElem != null && mDtdRootElem.length() > 0) {
                String wrongElem = null;
                
                /* Ugh. It is possible that we just don't know the prefix --
                 * in repairing mode it's assigned after this check. So for
                 * now, let's only verify the local name
                 */
                if (localName.equals(mDtdRootElem)) {
                    // good
                } else {
                    int lnLen = localName.length();
                    int oldLen = mDtdRootElem.length();
                    
                    if (oldLen > lnLen
                        && mDtdRootElem.endsWith(localName)
                        && mDtdRootElem.charAt(oldLen - lnLen - 1) == ':') {
                        // good also
                    } else {
                        if (prefix == null) { // doesn't and won't have one
                            wrongElem = localName;
                        } else if (prefix.length() == 0) { // don't know what it'd be
                            wrongElem = "[unknown]:"+localName;
                        } else {
                            wrongElem = prefix + ":" + localName;
                        }
                    }
                }
                if (wrongElem != null) {
                    reportValidationProblem(ErrorConsts.ERR_VLD_WRONG_ROOT, wrongElem, mDtdRootElem);
                }
            }
        }
        mState = STATE_TREE;
    }

    /*
    ///////////////////////////////////////////////////////////
    // Package methods, basic output problem reporting
    ///////////////////////////////////////////////////////////
     */

    protected static void throwOutputError(String msg)
        throws XMLStreamException
    {
        throw new XMLStreamException(msg);
    }

    protected static void throwOutputError(String format, Object arg)
        throws XMLStreamException
    {
        String msg = MessageFormat.format(format, new Object[] { arg });
        throwOutputError(msg);
    }

    
Method called when an illegal method (namespace-specific method
on non-ns writer) is called by the application.
/**
     * Method called when an illegal method (namespace-specific method
     * on non-ns writer) is called by the application.
     */
    protected static void reportIllegalMethod(String msg)
        throws XMLStreamException
    {
        throwOutputError(msg);
    }

    
This is the method called when an output method call violates structural well-formedness checks and WstxOutputProperties.P_OUTPUT_VALIDATE_STRUCTURE is is enabled. /**
     * This is the method called when an output method call violates
     * structural well-formedness checks
     * and {@link WstxOutputProperties#P_OUTPUT_VALIDATE_STRUCTURE} is
     * is enabled.
     */
    protected static void reportNwfStructure(String msg)
        throws XMLStreamException
    {
        throwOutputError(msg);
    }

    protected static void reportNwfStructure(String msg, Object arg)
        throws XMLStreamException
    {
        throwOutputError(msg, arg);
    }

    
This is the method called when an output method call violates content well-formedness checks and WstxOutputProperties.P_OUTPUT_VALIDATE_CONTENT is is enabled. /**
     * This is the method called when an output method call violates
     * content well-formedness checks
     * and {@link WstxOutputProperties#P_OUTPUT_VALIDATE_CONTENT} is
     * is enabled.
     */
    protected static void reportNwfContent(String msg)
        throws XMLStreamException
    {
        throwOutputError(msg);
    }

    protected static void reportNwfContent(String msg, Object arg)
        throws XMLStreamException
    {
        throwOutputError(msg, arg);
    }

    
This is the method called when an output method call violates attribute well-formedness checks (trying to output dup attrs) and WstxOutputProperties.P_OUTPUT_VALIDATE_NAMES is is enabled. /**
     * This is the method called when an output method call violates
     * attribute well-formedness checks (trying to output dup attrs)
     * and {@link WstxOutputProperties#P_OUTPUT_VALIDATE_NAMES} is
     * is enabled.
     */
    protected static void reportNwfAttr(String msg)
        throws XMLStreamException
    {
        throwOutputError(msg);
    }

    protected static void reportNwfAttr(String msg, Object arg)
        throws XMLStreamException
    {
        throwOutputError(msg, arg);
    }

    protected static void throwFromIOE(IOException ioe)
        throws XMLStreamException
    {
        throw new WstxIOException(ioe);
    }

    protected static void reportIllegalArg(String msg)
        throws IllegalArgumentException
    {
        throw new IllegalArgumentException(msg);
    }

    /*
    ///////////////////////////////////////////////////////////
    // Package methods, output validation problem reporting
    ///////////////////////////////////////////////////////////
     */

    protected void reportInvalidContent(int evtType)
        throws XMLStreamException
    {
        switch (mVldContent) {
        case XMLValidator.CONTENT_ALLOW_NONE:
            reportValidationProblem(ErrorConsts.ERR_VLD_EMPTY,
                                    getTopElementDesc(),
                                    ErrorConsts.tokenTypeDesc(evtType));
            break;
        case XMLValidator.CONTENT_ALLOW_WS:
            reportValidationProblem(ErrorConsts.ERR_VLD_NON_MIXED,
                                    getTopElementDesc());
            break;
        case XMLValidator.CONTENT_ALLOW_VALIDATABLE_TEXT:
        case XMLValidator.CONTENT_ALLOW_ANY_TEXT:
            /* Not 100% sure if this should ever happen... depends on
             * interpretation of 'any' content model?
             */
            reportValidationProblem(ErrorConsts.ERR_VLD_ANY,
                                    getTopElementDesc(),
                                    ErrorConsts.tokenTypeDesc(evtType));
            break;
        default: // should never occur:
            reportValidationProblem("Internal error: trying to report invalid content for "+evtType);
        }
    }

    public void reportValidationProblem(String msg, Location loc, int severity)
        throws XMLStreamException
    {
        reportProblem(new XMLValidationProblem(loc, msg, severity));
    }

    public void reportValidationProblem(String msg, int severity)
        throws XMLStreamException
    {
        reportProblem(new XMLValidationProblem(getValidationLocation(),
                                               msg, severity));
    }

    public void reportValidationProblem(String msg)
        throws XMLStreamException
    {
        reportProblem(new XMLValidationProblem(getValidationLocation(),
                                               msg,
                                               XMLValidationProblem.SEVERITY_ERROR));
    }

    public void reportValidationProblem(Location loc, String msg)
        throws XMLStreamException
    {
        reportProblem(new XMLValidationProblem(loc, msg));
    }

    public void reportValidationProblem(String format, Object arg)
        throws XMLStreamException
    {
        String msg = MessageFormat.format(format, new Object[] { arg });
        reportProblem(new XMLValidationProblem(getValidationLocation(),
                                                         msg));
    }

    public void reportValidationProblem(String format, Object arg, Object arg2)
        throws XMLStreamException
    {
        String msg = MessageFormat.format(format, new Object[] { arg, arg2 });
        reportProblem(new XMLValidationProblem(getValidationLocation(), msg));
    }

    protected void doReportProblem(XMLReporter rep, String probType, String msg, Location loc)
        throws XMLStreamException
    {
        if (loc == null) {
            loc = getLocation();
        }
        doReportProblem(rep, new XMLValidationProblem(loc, msg, XMLValidationProblem.SEVERITY_ERROR, probType));
    }

    protected void doReportProblem(XMLReporter rep, XMLValidationProblem prob)
        throws XMLStreamException
    {
        if (rep != null) {
            Location loc = prob.getLocation();
            if (loc == null) {
                loc = getLocation();
                prob.setLocation(loc);
            }
            // Backwards-compatibility fix: add non-null type, if missing:
            if (prob.getType() == null) {
                prob.setType(ErrorConsts.WT_VALIDATION);
            }
            // [WSTX-154]: was catching and dropping thrown exception: shouldn't.
            rep.report(prob.getMessage(), prob.getType(), prob, loc);
        }
    }

    
Method needed for error message generation
/**
     * Method needed for error message generation
     */
    protected abstract String getTopElementDesc();

    /*
    ///////////////////////////////////////////////////////////
    // Package methods, other
    ///////////////////////////////////////////////////////////
     */

    protected final char[] getCopyBuffer()
    {
        char[] buf = mCopyBuffer;
        if (buf == null) {
            mCopyBuffer = buf = mConfig.allocMediumCBuffer(DEFAULT_COPYBUFFER_LEN);
        }
        return buf;
    }

    protected final char[] getCopyBuffer(int minLen)
    {
        char[] buf = mCopyBuffer;
        if (buf == null || minLen > buf.length) {
            mCopyBuffer = buf = mConfig.allocMediumCBuffer(Math.max(DEFAULT_COPYBUFFER_LEN, minLen));
        }
        return buf;
    }

    @Override
    public String toString()
    {
        return "[StreamWriter: "+getClass()+", underlying outputter: "
            +((mWriter == null) ? "NULL" : mWriter.toString()+"]");
    }
}