content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.apache.chemistry.opencmis.commons.impl;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.math.BigDecimal;
  import java.math.BigInteger;
  import java.util.GregorianCalendar;
  
  import org.apache.chemistry.opencmis.commons.exceptions.CmisInvalidArgumentException;
  import org.apache.chemistry.opencmis.commons.exceptions.CmisRuntimeException;
  import org.w3c.dom.Document;
  import org.xmlpull.v1.XmlPullParser;
  import org.xmlpull.v1.XmlPullParserException;
  import org.xmlpull.v1.XmlSerializer;
  
  import android.util.Xml;
  
  public final class XMLUtils {
  
      private XMLUtils() {
      }
  
      // --------------
      // --- writer ---
      // --------------
  
      /**
       * Creates a new XML writer.
       */
      public static XmlSerializer createWriter(OutputStream out) throws IOException {
          assert out != null;
  
          XmlSerializer writer = Xml.newSerializer();
          writer.setOutput(out, IOUtils.UTF8);
          
          return writer;
      }
  
      /**
       * Starts a XML document.
       */
      public static void startXmlDocument(XmlSerializer writer) throws IOException {
          assert writer != null;
          
          writer.setPrefix(XMLConstants.PREFIX_ATOM, XMLConstants.NAMESPACE_ATOM);
          writer.setPrefix(XMLConstants.PREFIX_CMIS, XMLConstants.NAMESPACE_CMIS);
          writer.setPrefix(XMLConstants.PREFIX_RESTATOM, XMLConstants.NAMESPACE_RESTATOM);
          writer.setPrefix(XMLConstants.PREFIX_APACHE_CHEMISTY, XMLConstants.NAMESPACE_APACHE_CHEMISTRY);
  
          writer.startDocument("UTF-8", false);
      }
  
      /**
       * Ends a XML document.
       */
      public static void endXmlDocument(XmlSerializer writer) throws IOException {
          assert writer != null;
          
          // end document
          writer.endDocument();
          writer.flush();
          writer.toString();
      }
  
      /**
       * Writes a String tag.
       */
      public static void write(XmlSerializer writer, String prefix, String namespace, String tag, String value)
              throws IOException {
          assert writer != null;
  
          if (value == null) {
              return;
          }
  
          if (namespace == null) {
              writer.startTag(null, tag);
          } else {
              writer.startTag(namespace, tag);
          }
          writer.text(value);
          writer.endTag(namespace, tag);
      }
  
      /**
       * Writes an Integer tag.
       */
      public static void write(XmlSerializer writer, String prefix, String namespace, String tag, BigInteger value)
              throws IOException {
          assert writer != null;
  
          if (value == null) {
              return;
          }
  
          write(writer, prefix, namespace, tag, value.toString());
      }
  
      /**
       * Writes a Decimal tag.
       */
      public static void write(XmlSerializer writer, String prefix, String namespace, String tag, BigDecimal value)
              throws IOException {
          assert writer != null;
  
          if (value == null) {
              return;
          }
  
          write(writer, prefix, namespace, tag, value.toString());
      }
  
      /**
       * Writes a DateTime tag.
       */
      public static void write(XmlSerializer writer, String prefix, String namespace, String tag, GregorianCalendar value)
              throws IOException {
          assert writer != null;
  
          if (value == null) {
              return;
          }
  
          write(writer, prefix, namespace, tag, DateTimeHelper.formatXmlDateTime(value));
      }
  
      /**
       * Writes a Boolean tag.
       */
      public static void write(XmlSerializer writer, String prefix, String namespace, String tag, Boolean value)
              throws IOException {
          assert writer != null;
  
          if (value == null) {
              return;
          }
  
          write(writer, prefix, namespace, tag, value ? "true" : "false");
      }
  
      /**
       * Writes an Enum tag.
       */
      public static void write(XmlSerializer writer, String prefix, String namespace, String tag, Enum<?> value)
              throws IOException {
          assert writer != null;
  
          if (value == null) {
              return;
          }
  
          Object enumValue;
          try {
              enumValue = value.getClass().getMethod("value", new Class[0]).invoke(value, new Object[0]);
          } catch (Exception e) {
              throw new IllegalStateException("Cannot get enum value", e);
          }
  
          write(writer, prefix, namespace, tag, enumValue.toString());
      }
  
      // ---------------
      // ---- parser ---
      // ---------------
  
      /**
       * Creates a new XML parser with OpenCMIS default settings.
       */
      public static XmlPullParser createParser(InputStream stream) throws XmlPullParserException {
          XmlPullParser parser = Xml.newPullParser();
          parser.setInput(stream, IOUtils.UTF8);
          return parser;
      }
  
      /**
       * Moves the parser to the next element.
       */
      public static boolean next(XmlPullParser parser) {
          assert parser != null;
  
          try {
              if (hasNext(parser)) {
                  parser.next();
                  return true;
              }
              return false;
          } catch (Exception e) {
              // EOF exceptions
              return false;
          }
      }
  
      public static boolean hasNext(XmlPullParser parser) throws XmlPullParserException {
          assert parser != null;
  
          return parser.getEventType() != XmlPullParser.END_DOCUMENT;
      }
  
      /**
       * Skips a tag or subtree.
       */
      public static void skip(XmlPullParser parser) throws XmlPullParserException {
          assert parser != null;
  
          int level = 1;
          while (next(parser)) {
              int event = parser.getEventType();
              if (event == XmlPullParser.START_TAG) {
                  level++;
              } else if (event == XmlPullParser.END_TAG) {
                  level--;
                  if (level == 0) {
                      break;
                  }
              }
          }
  
          next(parser);
      }
  
      /**
       * Moves the parser to the next start element.
       * 
       * @return <code>true</code> if another start element has been found,
       *         <code>false</code> otherwise
       */
      public static boolean findNextStartElemenet(XmlPullParser parser) throws XmlPullParserException, IOException {
          assert parser != null;
  
          while (true) {
              int event = parser.getEventType();
  
              if (event == XmlPullParser.START_TAG) {
                  return true;
              }
  
              if (hasNext(parser)) {
                  parser.next();
              } else {
                  return false;
              }
          }
      }
  
      /**
       * Parses a tag that contains text.
       */
      public static String readText(XmlPullParser parser, int maxLength) throws XmlPullParserException {
          assert parser != null;
          assert maxLength >= 0;
  
          StringBuilder sb = new StringBuilder(128);
  
          next(parser);
  
          while (true) {
              int event = parser.getEventType();
              if (event == XmlPullParser.END_TAG) {
                  break;
              } else if (event == XmlPullParser.TEXT) {
                  int len = 0;
                  if (parser.getText() != null) {
                      len = parser.getText().length();
                  }
                  if (len > 0) {
                      if (sb.length() + len > maxLength) {
                          throw new CmisInvalidArgumentException("String limit exceeded!");
                      }
                      sb.append(parser.getText());
                  }
              } else if (event == XmlPullParser.START_TAG) {
                  throw new XmlPullParserException("Unexpected tag: " + parser.getName());
              }
  
              if (!next(parser)) {
                  break;
              }
          }
  
          next(parser);
  
          return sb.toString();
      }
  
      // ------------------
      // ---- DOM stuff ---
      // ------------------
      
      public static Document newDomDocument() {
          throw new CmisRuntimeException("This method should never be used on Android!");
      }
  }
  