xmlparser.java

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  }

  public int nextTag()
    throws XMLStreamException
  {
    do
      {
        switch (next())
          {
          case XMLStreamConstants.START_ELEMENT:
          case XMLStreamConstants.END_ELEMENT:
          case XMLStreamConstants.CHARACTERS:
          case XMLStreamConstants.SPACE:
          case XMLStreamConstants.COMMENT:
          case XMLStreamConstants.PROCESSING_INSTRUCTION:
            break;
          default:
            throw new XMLStreamException("Unexpected event type: " + event);
          }
      }
    while (event != XMLStreamConstants.START_ELEMENT &&
           event != XMLStreamConstants.END_ELEMENT);
    return event;
  }

  public void require(int type, String namespaceURI, String localName)
    throws XMLStreamException
  {
    if (event != type)
      throw new XMLStreamException("Current event type is " + event);
    if (event == XMLStreamConstants.START_ELEMENT ||
        event == XMLStreamConstants.END_ELEMENT)
      {
        String ln = getLocalName();
        if (!ln.equals(localName))
          throw new XMLStreamException("Current local-name is " + ln);
        String uri = getNamespaceURI();
        if ((uri == null && namespaceURI != null) ||
            (uri != null && !uri.equals(namespaceURI)))
          throw new XMLStreamException("Current namespace URI is " + uri);
      }
  }

  public boolean standaloneSet()
  {
    return (xmlStandalone != null);
  }

  public boolean hasNext()
    throws XMLStreamException
  {
    if (event == XMLStreamConstants.END_DOCUMENT)
      return false;
    if (!lookahead)
      {
        next();
        lookahead = true;
      }
    return event != -1;
  }
  
  public int next()
    throws XMLStreamException
  {
    if (lookahead)
      {
        lookahead = false;
        return event;
      }
    if (event == XMLStreamConstants.END_ELEMENT)
      {
        // Pop namespace context
        if (namespaceAware && !namespaces.isEmpty())
          namespaces.removeFirst();
        // Pop base context
        if (baseAware && !bases.isEmpty())
          bases.removeFirst();
      }
    if (!startEntityStack.isEmpty())
      {
        String entityName = (String) startEntityStack.removeFirst();
        buf.setLength(0);
        buf.append(entityName);
        event = START_ENTITY;
        return extendedEventTypes ? event : next();
      }
    else if (!endEntityStack.isEmpty())
      {
        String entityName = (String) endEntityStack.removeFirst();
        buf.setLength(0);
        buf.append(entityName);
        event = END_ENTITY;
        return extendedEventTypes ? event : next();
      }
    try
      {
        if (!input.initialized)
          input.init();
        switch (state)
          {
          case CONTENT:
            if (tryRead(TEST_END_ELEMENT))
              {
                readEndElement();
                if (stack.isEmpty())
                  state = MISC;
                event = XMLStreamConstants.END_ELEMENT;
              }
            else if (tryRead(TEST_COMMENT))
              {
                readComment(false);
                event = XMLStreamConstants.COMMENT;
              }
            else if (tryRead(TEST_PI))
              {
                readPI(false);
                event = XMLStreamConstants.PROCESSING_INSTRUCTION;
              }
            else if (tryRead(TEST_CDATA))
              {
                readCDSect();
                event = XMLStreamConstants.CDATA;
              }
            else if (tryRead(TEST_START_ELEMENT))
              {
                state = readStartElement();
                event = XMLStreamConstants.START_ELEMENT;
              }
            else
              {
                // Check for character reference or predefined entity
                mark(8);
                int c = readCh();
                if (c == 0x26) // '&'
                  {
                    c = readCh();
                    if (c == 0x23) // '#'
                      {
                        reset();
                        event = readCharData(null);
                      }
                    else
                      {
                        // entity reference
                        reset();
                        readCh(); // &
                        readReference();
                        String ref = buf.toString();
                        String text = (String) PREDEFINED_ENTITIES.get(ref);
                        if (text != null)
                          {
                            event = readCharData(text);
                          }
                        else if (replaceERefs && !isUnparsedEntity(ref))
                          {
                            // this will report a start-entity event
                            boolean external = false;
                            if (doctype != null)
                              {
                                Object entity = doctype.getEntity(ref);
                                if (entity instanceof ExternalIds)
                                  external = true;
                              }
                            expandEntity(ref, false, external);
                            event = next();
                          }
                        else
                          {
                            event = XMLStreamConstants.ENTITY_REFERENCE;
                          }
                      }
                  }
                else
                  {
                    reset();
                    event = readCharData(null);
                    if (validating && doctype != null)
                      validatePCData(buf.toString());
                  }
              }
            break;
          case EMPTY_ELEMENT:
            String elementName = (String) stack.removeLast();
            buf.setLength(0);
            buf.append(elementName);
            state = stack.isEmpty() ? MISC : CONTENT;
            event = XMLStreamConstants.END_ELEMENT;
            if (validating && doctype != null)
              endElementValidationHook();
            break;
          case INIT: // XMLDecl?
            if (tryRead(TEST_XML_DECL))
              readXMLDecl();
            input.finalizeEncoding();
            event = XMLStreamConstants.START_DOCUMENT;
            state = PROLOG;
            break;
          case PROLOG: // Misc* (doctypedecl Misc*)?
            skipWhitespace();
            if (doctype == null && tryRead(TEST_DOCTYPE_DECL))
              {
                readDoctypeDecl();
                event = XMLStreamConstants.DTD;
              }
            else if (tryRead(TEST_COMMENT))
              {
                readComment(false);
                event = XMLStreamConstants.COMMENT;
              }
            else if (tryRead(TEST_PI))
              {
                readPI(false);
                event = XMLStreamConstants.PROCESSING_INSTRUCTION;
              }
            else if (tryRead(TEST_START_ELEMENT))
              {
                state = readStartElement();
                event = XMLStreamConstants.START_ELEMENT;
              }
            else
              {
                int c = readCh();
                error("no root element: U+" + Integer.toHexString(c));
              }
            break;
          case MISC: // Comment | PI | S
            skipWhitespace();
            if (tryRead(TEST_COMMENT))
              {
                readComment(false);
                event = XMLStreamConstants.COMMENT;
              }
            else if (tryRead(TEST_PI))
              {
                readPI(false);
                event = XMLStreamConstants.PROCESSING_INSTRUCTION;
              }
            else
              {
                if (event == XMLStreamConstants.END_DOCUMENT)
                  throw new NoSuchElementException();
                int c = readCh();
                if (c != -1)
                  error("Only comments and PIs may appear after " +
                        "the root element");
                event = XMLStreamConstants.END_DOCUMENT;
              }
            break;
          default:
            event = -1;
          }
        return event;
      }
    catch (IOException e)
      {
        XMLStreamException e2 = new XMLStreamException();
        e2.initCause(e);
        throw e2;
      }
  }

  // package private

  /**
   * Returns the current element name.
   */
  String getCurrentElement()
  {
    return (String) stack.getLast();
  }

  // private

  private void mark(int limit)
    throws IOException
  {
    input.mark(limit);
  }

  private void reset()
    throws IOException
  {
    input.reset();
  }

  private int read()
    throws IOException
  {
    return input.read();
  }

  private int read(int[] b, int off, int len)
    throws IOException
  {
    return input.read(b, off, len);
  }
  
  /**
   * Parsed character read.
   */
  private int readCh()
    throws IOException, XMLStreamException
  {
    int c = read();
    if (expandPE && c == 0x25) // '%'
      {
        if (peIsError)
          error("PE reference within decl in internal subset.");
        expandPEReference();
        return readCh();
      }
    return c;
  }

  /**
   * Reads the next character, ensuring it is the character specified.
   * @param delim the character to match
   * @exception XMLStreamException if the next character is not the
   * specified one
   */
  private void require(char delim)
    throws IOException, XMLStreamException
  {
    mark(1);
    int c = readCh();
    if (delim != c)
      {
        reset();
        error("required character (got U+" + Integer.toHexString(c) + ")",
              new Character(delim));
      }
  }

  /**
   * Reads the next few characters, ensuring they match the string specified.
   * @param delim the string to match
   * @exception XMLStreamException if the next characters do not match the
   * specified string
   */
  private void require(String delim)
    throws IOException, XMLStreamException
  {
    char[] chars = delim.toCharArray();
    int len = chars.length;
    mark(len);
    int off = 0;
    do
      {
        int l2 = read(tmpBuf, off, len - off);
        if (l2 == -1)
          {
            reset();
            error("EOF before required string", delim);
          }
        off += l2;
      }
    while (off < len);
    for (int i = 0; i < chars.length; i++)
      {
        if (chars[i] != tmpBuf[i])
          {
            reset();
            error("required string", delim);
          }
      }
  }

  /**
   * Try to read a single character. On failure, reset the stream.
   * @param delim the character to test
   * @return true if the character matched delim, false otherwise.
   */
  private boolean tryRead(char delim)
    throws IOException, XMLStreamException
  {
    mark(1);
    int c = readCh();
    if (delim != c)
      {
        reset();
        return false;
      }
    return true;
  }

  /**
   * Tries to read the specified characters.
   * If successful, the stream is positioned after the last character,
   * otherwise it is reset.
   * @param test the string to test
   * @return true if the characters matched the test string, false otherwise.
   */
  private boolean tryRead(String test)
    throws IOException
  {
    char[] chars = test.toCharArray();
    int len = chars.length;
    mark(len);
    int count = 0;
    int l2 = read(tmpBuf, 0, len);
    if (l2 == -1)
      {
        reset();
        return false;
      }
    count += l2;
    while (count < len)
      {
        // force read
        int c = read();
        if (c == -1)
          {
            reset();
            return false;
          }
        tmpBuf[count++] = (char) c;
      }
    for (int i = 0; i < len; i++)
      {
        if (chars[i] != tmpBuf[i])
          {
            reset();
            return false;
          }
      }
    return true;
  }

  /**
   * Reads characters until the specified test string is encountered.
   * @param delim the string delimiting the end of the characters
   */
  private void readUntil(String delim)
    throws IOException, XMLStreamException
  {
    int startLine = input.line;
    try
      {
        while (!tryRead(delim))
          {
            int c = readCh();
            if (c == -1)
              throw new EOFException();
            else if (input.xml11)
              {
                if (!isXML11Char(c) || isXML11RestrictedChar(c))
                  error("illegal XML 1.1 character",
                        "U+" + Integer.toHexString(c));
              }
            else if (!isChar(c))
              error("illegal XML character", 
                    "U+" + Integer.toHexString(c));
            buf.append(Character.toChars(c));
          }
      }
    catch (EOFException e)
      {
        error("end of input while looking for delimiter "+
              "(started on line " + startLine + ')', delim);
      }
  }

  /**
   * Reads any whitespace characters.