com.ctc.wstx.sw.BaseNsStreamWriter Maven / Gradle / Ivy
/* Woodstox XML processor
*
* Copyright (c) 2004- Tatu Saloranta, [email protected]
*
* Licensed under the License specified in the 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 javax.xml.XMLConstants;
import javax.xml.namespace.NamespaceContext;
import javax.xml.namespace.QName;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.events.StartElement;
import org.codehaus.stax2.ri.typed.AsciiValueEncoder;
import com.ctc.wstx.api.EmptyElementHandler;
import com.ctc.wstx.api.WriterConfig;
import com.ctc.wstx.cfg.ErrorConsts;
import com.ctc.wstx.cfg.XmlConsts;
import com.ctc.wstx.exc.WstxIOException;
import com.ctc.wstx.util.DefaultXmlSymbolTable;
/**
* Mid-level base class of namespace-aware stream writers. Contains
* shared functionality between repairing and non-repairing implementations.
*/
public abstract class BaseNsStreamWriter
extends TypedStreamWriter
{
/*
////////////////////////////////////////////////////
// Constants
////////////////////////////////////////////////////
*/
final protected static String sPrefixXml = DefaultXmlSymbolTable.getXmlSymbol();
final protected static String sPrefixXmlns = DefaultXmlSymbolTable.getXmlnsSymbol();
final protected static String ERR_NSDECL_WRONG_STATE =
"Trying to write a namespace declaration when there is no open start element.";
/*
////////////////////////////////////////////////////
// Configuration (options, features)
////////////////////////////////////////////////////
*/
// // // Additional specific config flags base class doesn't have
/**
* True, if writer needs to automatically output namespace declarations
* (we are in repairing mode)
*/
final protected boolean mAutomaticNS;
final protected EmptyElementHandler mEmptyElementHandler;
/*
////////////////////////////////////////////////////
// State information
////////////////////////////////////////////////////
*/
protected SimpleOutputElement mCurrElem = SimpleOutputElement.createRoot();
/**
* Optional "root" namespace context that application can set. If so,
* it can be used to lookup namespace/prefix mappings
*/
protected NamespaceContext mRootNsContext = null;
/*
////////////////////////////////////////////////////
// Pool for recycling SimpleOutputElement instances
////////////////////////////////////////////////////
*/
/* Note: although pooling of cheap objects like SimpleOutputElement
* is usually not a good idea, here profiling showed it to be a
* significant improvement. As long as instances are ONLY reused
* within context of a single writer, they stay in cheap ("Eden")
* GC area, and thus it should be a win.
*/
protected SimpleOutputElement mOutputElemPool = null;
/**
* Although pooled objects are small, let's limit the pool size
* nonetheless, to optimize memory usage for deeply nested
* documents. In general, even just low number like 4 levels gets
* decent return, but 8 should get 99% hit rate.
*/
final static int MAX_POOL_SIZE = 8;
protected int mPoolSize = 0;
/*
////////////////////////////////////////////////////
// Life-cycle (ctors)
////////////////////////////////////////////////////
*/
public BaseNsStreamWriter(XmlWriter xw, String enc, WriterConfig cfg,
boolean repairing)
{
super(xw, enc, cfg);
mAutomaticNS = repairing;
mEmptyElementHandler = cfg.getEmptyElementHandler();
}
/*
////////////////////////////////////////////////////
// XMLStreamWriter API
////////////////////////////////////////////////////
*/
public NamespaceContext getNamespaceContext() {
return mCurrElem;
}
public String getPrefix(String uri) {
return mCurrElem.getPrefix(uri);
}
public abstract void setDefaultNamespace(String uri)
throws XMLStreamException;
/**
*
* Note: Root namespace context works best if automatic prefix
* creation ("namespace/prefix repairing" in StAX lingo) is enabled.
*/
public void setNamespaceContext(NamespaceContext ctxt)
throws XMLStreamException
{
// This is only allowed before root element output:
if (mState != STATE_PROLOG) {
throwOutputError("Called setNamespaceContext() after having already output root element.");
}
mRootNsContext = ctxt;
mCurrElem.setRootNsContext(ctxt);
}
public void setPrefix(String prefix, String uri)
throws XMLStreamException
{
if (prefix == null) {
throw new NullPointerException("Can not pass null 'prefix' value");
}
// Are we actually trying to set the default namespace?
if (prefix.length() == 0) {
setDefaultNamespace(uri);
return;
}
if (uri == null) {
throw new NullPointerException("Can not pass null 'uri' value");
}
/* 25-Sep-2004, TSa: Let's check that "xml" and "xmlns" are not
* (re-)defined to any other value, nor that value they
* are bound to are bound to other prefixes.
*/
/* 01-Apr-2005, TSa: And let's not leave it optional: such
* bindings should never succeed.
*/
// ... perhaps it really should be optional though?
{
if (prefix.equals(sPrefixXml)) { // prefix "xml"
if (!uri.equals(XMLConstants.XML_NS_URI)) {
throwOutputError(ErrorConsts.ERR_NS_REDECL_XML, uri);
}
} else if (prefix.equals(sPrefixXmlns)) { // prefix "xmlns"
if (!uri.equals(XMLConstants.XMLNS_ATTRIBUTE_NS_URI)) {
throwOutputError(ErrorConsts.ERR_NS_REDECL_XMLNS, uri);
}
} else {
// Neither of prefixes.. but how about URIs?
if (uri.equals(XMLConstants.XML_NS_URI)) {
throwOutputError(ErrorConsts.ERR_NS_REDECL_XML_URI, prefix);
} else if (uri.equals(XMLConstants.XMLNS_ATTRIBUTE_NS_URI)) {
throwOutputError(ErrorConsts.ERR_NS_REDECL_XMLNS_URI, prefix);
}
}
/* 05-Feb-2005, TSa: Also, as per namespace specs; the 'empty'
* namespace URI can not be bound as a non-default namespace
* (ie. for any actual prefix)
*/
/* 04-Feb-2005, TSa: Namespaces 1.1 does allow this, though,
* so for xml 1.1 documents we need to allow it
*/
if (!mXml11) {
if (uri.length() == 0) {
throwOutputError(ErrorConsts.ERR_NS_EMPTY);
}
}
}
doSetPrefix(prefix, uri);
}
/**
* It's assumed calling this method implies caller just wants to add
* an attribute that does not belong to any namespace; as such no
* namespace checking or prefix generation is needed.
*/
public void writeAttribute(String localName, String value)
throws XMLStreamException
{
// No need to set mAnyOutput, nor close the element
if (!mStartElementOpen && mCheckStructure) {
reportNwfStructure(ErrorConsts.WERR_ATTR_NO_ELEM);
}
doWriteAttr(localName, null, null, value);
}
public abstract void writeAttribute(String nsURI, String localName, String value)
throws XMLStreamException;
public abstract void writeAttribute(String prefix, String nsURI,
String localName, String value)
throws XMLStreamException;
/**
*
* Note: It is assumed caller just wants the element to belong to whatever
* is the current default namespace.
*/
public void writeEmptyElement(String localName)
throws XMLStreamException
{
checkStartElement(localName, null);
if (mValidator != null) {
mValidator.validateElementStart(localName, XmlConsts.ELEM_NO_NS_URI, XmlConsts.ELEM_NO_PREFIX);
}
mEmptyElement = true;
if (mOutputElemPool != null) {
SimpleOutputElement newCurr = mOutputElemPool;
mOutputElemPool = newCurr.reuseAsChild(mCurrElem, localName);
--mPoolSize;
mCurrElem = newCurr;
} else {
mCurrElem = mCurrElem.createChild(localName);
}
doWriteStartTag(localName);
}
public void writeEmptyElement(String nsURI, String localName)
throws XMLStreamException
{
writeStartOrEmpty(localName, nsURI);
mEmptyElement = true;
}
public void writeEmptyElement(String prefix, String localName, String nsURI)
throws XMLStreamException
{
writeStartOrEmpty(prefix, localName, nsURI);
mEmptyElement = true;
}
public void writeEndElement()
throws XMLStreamException
{
doWriteEndTag(null, mCfgAutomaticEmptyElems);
}
/**
* This method is assumed to just use default namespace (if any),
* and no further checks should be done.
*/
public void writeStartElement(String localName)
throws XMLStreamException
{
checkStartElement(localName, null);
if (mValidator != null) {
mValidator.validateElementStart(localName, XmlConsts.ELEM_NO_NS_URI, XmlConsts.ELEM_NO_PREFIX);
}
mEmptyElement = false;
if (mOutputElemPool != null) {
SimpleOutputElement newCurr = mOutputElemPool;
mOutputElemPool = newCurr.reuseAsChild(mCurrElem, localName);
--mPoolSize;
mCurrElem = newCurr;
} else {
mCurrElem = mCurrElem.createChild(localName);
}
doWriteStartTag(localName);
}
public void writeStartElement(String nsURI, String localName)
throws XMLStreamException
{
writeStartOrEmpty(localName, nsURI);
mEmptyElement = false;
}
public void writeStartElement(String prefix, String localName, String nsURI)
throws XMLStreamException
{
writeStartOrEmpty(prefix, localName, nsURI);
mEmptyElement = false;
}
protected void writeTypedAttribute(String prefix, String nsURI, String localName,
AsciiValueEncoder enc)
throws XMLStreamException
{
if (!mStartElementOpen) {
throwOutputError(ErrorConsts.WERR_ATTR_NO_ELEM);
}
if (mCheckAttrs) { // still need to ensure no duplicate attrs?
mCurrElem.checkAttrWrite(nsURI, localName);
}
try {
if (mValidator == null) {
if (prefix == null || prefix.length() == 0) {
mWriter.writeTypedAttribute(localName, enc);
} else {
mWriter.writeTypedAttribute(prefix, localName, enc);
}
} else {
mWriter.writeTypedAttribute
(prefix, localName, nsURI, enc, mValidator, getCopyBuffer());
}
} catch (IOException ioe) {
throw new WstxIOException(ioe);
}
}
/*
////////////////////////////////////////////////////
// Remaining XMLStreamWriter2 methods (StAX2)
////////////////////////////////////////////////////
*/
/**
* Similar to {@link #writeEndElement}, but never allows implicit
* creation of empty elements.
*/
public void writeFullEndElement()
throws XMLStreamException
{
doWriteEndTag(null, false);
}
/*
////////////////////////////////////////////////////
// Remaining ValidationContext methods (StAX2)
////////////////////////////////////////////////////
*/
public QName getCurrentElementName()
{
return mCurrElem.getName();
}
public String getNamespaceURI(String prefix) {
return mCurrElem.getNamespaceURI(prefix);
}
/*
//////////////////////////////////////////////////////////
// Implementations for base-class defined abstract methods
//////////////////////////////////////////////////////////
*/
/**
* Method called by {@link javax.xml.stream.XMLEventWriter} implementation
* (instead of the version
* that takes no argument), so that we can verify it does match the
* start element, if necessary
*/
public void writeEndElement(QName name)
throws XMLStreamException
{
doWriteEndTag(mCheckStructure ? name : null, mCfgAutomaticEmptyElems);
}
/**
* 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.
*
* @param emptyElem If true, the element being closed is an empty
* element; if false, a separate stand-alone start element.
*/
protected void closeStartElement(boolean emptyElem)
throws XMLStreamException
{
mStartElementOpen = false;
try {
if (emptyElem) {
mWriter.writeStartTagEmptyEnd();
} else {
mWriter.writeStartTagEnd();
}
} catch (IOException ioe) {
throw new WstxIOException(ioe);
}
if (mValidator != null) {
mVldContent = mValidator.validateElementAndAttributes();
}
// Need bit more special handling for empty elements...
if (emptyElem) {
SimpleOutputElement curr = mCurrElem;
mCurrElem = curr.getParent();
if (mCurrElem.isRoot()) { // Did we close the root? (isRoot() returns true for the virtual "document node")
mState = STATE_EPILOG;
}
if (mValidator != null) {
mVldContent = mValidator.validateElementEnd
(curr.getLocalName(), curr.getNamespaceURI(), curr.getPrefix());
}
if (mPoolSize < MAX_POOL_SIZE) {
curr.addToPool(mOutputElemPool);
mOutputElemPool = curr;
++mPoolSize;
}
}
}
protected String getTopElementDesc() {
return mCurrElem.getNameDesc();
}
/*
////////////////////////////////////////////////////
// Package methods sub-classes may also need
////////////////////////////////////////////////////
*/
/**
* Method that is called to ensure that we can start writing an
* element, both from structural point of view, and from syntactic
* (close previously open start element, if any).
*/
protected void checkStartElement(String localName, String prefix)
throws XMLStreamException
{
// Need to finish an open start element?
if (mStartElementOpen) {
closeStartElement(mEmptyElement);
} else if (mState == STATE_PROLOG) {
verifyRootElement(localName, prefix);
} else if (mState == STATE_EPILOG) {
if (mCheckStructure) {
String name = (prefix == null || prefix.length() == 0) ?
localName : (prefix + ":" + localName);
reportNwfStructure(ErrorConsts.WERR_PROLOG_SECOND_ROOT, name);
}
/* When outputting a fragment, need to reset this to the
* tree. No point in trying to verify the root element?
*/
mState = STATE_TREE;
}
}
protected final void doWriteAttr(String localName, String nsURI, String prefix,
String value)
throws XMLStreamException
{
if (mCheckAttrs) { // still need to ensure no duplicate attrs?
mCurrElem.checkAttrWrite(nsURI, localName);
}
if (mValidator != null) {
/* No need to get it normalized... even if validator does normalize
* it, we don't use that for anything
*/
mValidator.validateAttribute(localName, nsURI, prefix, value);
}
try {
int vlen = value.length();
// Worthwhile to make a local copy?
if (vlen >= ATTR_MIN_ARRAYCOPY) {
char[] buf = mCopyBuffer;
if (buf == null) {
mCopyBuffer = buf = mConfig.allocMediumCBuffer(DEFAULT_COPYBUFFER_LEN);
}
/* Ok, and in unlikely case of attribute values longer than
* buffer... for now, let's just skip those case
*/
if (vlen <= buf.length) {
value.getChars(0, vlen, buf, 0);
if (prefix != null && prefix.length() > 0) {
mWriter.writeAttribute(prefix, localName, buf, 0, vlen);
} else {
mWriter.writeAttribute(localName, buf, 0, vlen);
}
return;
}
}
if (prefix != null && prefix.length() > 0) {
mWriter.writeAttribute(prefix, localName, value);
} else {
mWriter.writeAttribute(localName, value);
}
} catch (IOException ioe) {
throw new WstxIOException(ioe);
}
}
protected final void doWriteAttr(String localName, String nsURI, String prefix,
char[] buf, int start, int len)
throws XMLStreamException
{
if (mCheckAttrs) { // still need to ensure no duplicate attrs?
mCurrElem.checkAttrWrite(nsURI, localName);
}
if (mValidator != null) {
/* No need to get it normalized... even if validator does normalize
* it, we don't use that for anything
*/
mValidator.validateAttribute(localName, nsURI, prefix, buf, start, len);
}
try {
if (prefix != null && prefix.length() > 0) {
mWriter.writeAttribute(prefix, localName, buf, start, len);
} else {
mWriter.writeAttribute(localName, buf, start, len);
}
} catch (IOException ioe) {
throw new WstxIOException(ioe);
}
}
protected void doWriteNamespace(String prefix, String nsURI)
throws XMLStreamException
{
try {
int vlen = nsURI.length();
// Worthwhile to make a local copy?
if (vlen >= ATTR_MIN_ARRAYCOPY) {
char[] buf = mCopyBuffer;
if (buf == null) {
mCopyBuffer = buf = mConfig.allocMediumCBuffer(DEFAULT_COPYBUFFER_LEN);
}
// Let's not bother with too long, though
if (vlen <= buf.length) {
nsURI.getChars(0, vlen, buf, 0);
mWriter.writeAttribute(XMLConstants.XMLNS_ATTRIBUTE, prefix, buf, 0, vlen);
return;
}
}
mWriter.writeAttribute(XMLConstants.XMLNS_ATTRIBUTE, prefix, nsURI);
} catch (IOException ioe) {
throw new WstxIOException(ioe);
}
}
protected void doWriteDefaultNs(String nsURI)
throws XMLStreamException
{
try {
int vlen = (nsURI == null) ? 0 : nsURI.length();
// Worthwhile to make a local copy?
if (vlen >= ATTR_MIN_ARRAYCOPY) {
char[] buf = mCopyBuffer;
if (buf == null) {
mCopyBuffer = buf = mConfig.allocMediumCBuffer(DEFAULT_COPYBUFFER_LEN);
}
// Let's not bother with too long, though
if (vlen <= buf.length) {
nsURI.getChars(0, vlen, buf, 0);
mWriter.writeAttribute(XMLConstants.XMLNS_ATTRIBUTE, buf, 0, vlen);
return;
}
}
mWriter.writeAttribute(XMLConstants.XMLNS_ATTRIBUTE, nsURI);
} catch (IOException ioe) {
throw new WstxIOException(ioe);
}
}
protected final void doWriteStartTag(String localName)
throws XMLStreamException
{
mAnyOutput = true;
mStartElementOpen = true;
try {
mWriter.writeStartTagStart(localName);
} catch (IOException ioe) {
throw new WstxIOException(ioe);
}
}
protected final void doWriteStartTag(String prefix, String localName)
throws XMLStreamException
{
mAnyOutput = true;
mStartElementOpen = true;
try {
boolean hasPrefix = (prefix != null && prefix.length() > 0);
if (hasPrefix) {
mWriter.writeStartTagStart(prefix, localName);
} else {
mWriter.writeStartTagStart(localName);
}
} catch (IOException ioe) {
throw new WstxIOException(ioe);
}
}
/**
*
* @param expName Name that the closing element should have; null
* if whatever is in stack should be used
* @param allowEmpty If true, is allowed to create the empty element
* if the closing element was truly empty; if false, has to write
* the full empty element no matter what
*/
protected void doWriteEndTag(QName expName, boolean allowEmpty)
throws XMLStreamException
{
/* First of all, do we need to close up an earlier empty element?
* (open start element that was not created via call to
* writeEmptyElement gets handled later on)
*/
if (mStartElementOpen && mEmptyElement) {
mEmptyElement = false;
closeStartElement(true);
}
// Better have something to close... (to figure out what to close)
if (mState != STATE_TREE) {
// Have to always throw exception... don't necessarily know the name
reportNwfStructure("No open start element, when trying to write end element");
}
SimpleOutputElement thisElem = mCurrElem;
String prefix = thisElem.getPrefix();
String localName = thisElem.getLocalName();
String nsURI = thisElem.getNamespaceURI();
// Ok, and then let's pop that element from the stack
mCurrElem = thisElem.getParent();
// Need to return the instance to pool?
if (mPoolSize < MAX_POOL_SIZE) {
thisElem.addToPool(mOutputElemPool);
mOutputElemPool = thisElem;
++mPoolSize;
}
if (mCheckStructure) {
if (expName != null) {
// Let's only check the local name, for now...
if (!localName.equals(expName.getLocalPart())) {
/* Only gets called when trying to output an XMLEvent... in
* which case names can actually be compared
*/
reportNwfStructure("Mismatching close element local name, '"+localName+"'; expected '"+expName.getLocalPart()+"'.");
}
}
}
/* Now, do we have an unfinished start element (created via
* writeStartElement() earlier)?
*/
if (mStartElementOpen) {
/* Can't/shouldn't call closeStartElement, but need to do same
* processing. Thus, this is almost identical to closeStartElement:
*/
if (mValidator != null) {
/* Note: return value is not of much use, since the
* element will be closed right away...
*/
mVldContent = mValidator.validateElementAndAttributes();
}
mStartElementOpen = false;
try {
//If an EmptyElementHandler is provided use it to determine if allowEmpty is set
if (mEmptyElementHandler != null) {
allowEmpty = mEmptyElementHandler.allowEmptyElement(prefix, localName, nsURI, allowEmpty);
}
// We could write an empty element, implicitly?
if (allowEmpty) {
mWriter.writeStartTagEmptyEnd();
if (mCurrElem.isRoot()) {
mState = STATE_EPILOG;
}
if (mValidator != null) {
mVldContent = mValidator.validateElementEnd(localName, nsURI, prefix);
}
return;
}
// Nah, need to close open elem, and then output close elem
mWriter.writeStartTagEnd();
} catch (IOException ioe) {
throw new WstxIOException(ioe);
}
}
try {
mWriter.writeEndTag(prefix, localName);
} catch (IOException ioe) {
throw new WstxIOException(ioe);
}
if (mCurrElem.isRoot()) {
mState = STATE_EPILOG;
}
// Ok, time to validate...
if (mValidator != null) {
mVldContent = mValidator.validateElementEnd(localName, nsURI, prefix);
}
}
/*
////////////////////////////////////////////////////
// More abstract methods for sub-classes to implement
////////////////////////////////////////////////////
*/
public abstract void doSetPrefix(String prefix, String uri)
throws XMLStreamException;
public abstract void writeDefaultNamespace(String nsURI)
throws XMLStreamException;
public abstract void writeNamespace(String prefix, String nsURI)
throws XMLStreamException;
public abstract void writeStartElement(StartElement elem)
throws XMLStreamException;
protected abstract void writeStartOrEmpty(String localName, String nsURI)
throws XMLStreamException;
protected abstract void writeStartOrEmpty(String prefix, String localName, String nsURI)
throws XMLStreamException;
}