code: /*
   * 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.
   */
  /*
   * $Id$
   */
  package org.apache.xalan.xsltc.dom;
  
  import org.apache.xalan.xsltc.DOM;
  import org.apache.xalan.xsltc.DOMEnhancedForDTM;
  import org.apache.xalan.xsltc.StripFilter;
  import org.apache.xalan.xsltc.runtime.AbstractTranslet;
  import org.apache.xalan.xsltc.runtime.Hashtable;
  import org.apache.xml.dtm.DTM;
  import org.apache.xml.dtm.DTMWSFilter;
  
  /**
   * A wrapper class that adapts the
   * {@link org.apache.xml.dtm.DTMWSFilter DTMWSFilter} interface to the XSLTC
   * DOM {@link org.apache.xalan.xsltc.StripFilter StripFilter} interface.
   */
  public class DOMWSFilter implements DTMWSFilter {
  
      private AbstractTranslet m_translet;
      private StripFilter m_filter;
      
      // The Hashtable for DTM to mapping array
      private Hashtable m_mappings;
      
      // Cache the DTM and mapping that are used last time
      private DTM m_currentDTM;
      private short[] m_currentMapping;
  
      /**
       * Construct an adapter connecting the <code>DTMWSFilter</code> interface
       * to the <code>StripFilter</code> interface.
       *
       * @param translet A translet that also implements the StripFilter
       * interface.
       *
       * @see org.apache.xml.dtm.DTMWSFilter
       * @see org.apache.xalan.xsltc.StripFilter
       */
      public DOMWSFilter(AbstractTranslet translet) {
          m_translet = translet;
          m_mappings = new Hashtable();
  
          if (translet instanceof StripFilter) {
              m_filter = (StripFilter) translet;
          }
      }
  
      /**
       * Test whether whitespace-only text nodes are visible in the logical
       * view of <code>DTM</code>. Normally, this function
       * will be called by the implementation of <code>DTM</code>;
       * it is not normally called directly from
       * user code.
       *
       * @param node int handle of the node.
       * @param dtm the DTM that owns this node
       * @return one of <code>NOTSTRIP</code>, <code>STRIP</code> or
       * <code>INHERIT</code>.
       */
      public short getShouldStripSpace(int node, DTM dtm) {
          if (m_filter != null && dtm instanceof DOM) {
              DOM dom = (DOM)dtm;
              int type = 0;
  
              if (dtm instanceof DOMEnhancedForDTM) {
                  DOMEnhancedForDTM mappableDOM = (DOMEnhancedForDTM)dtm;
                  
                  short[] mapping;
                  if (dtm == m_currentDTM) {
                      mapping = m_currentMapping;
                  }
                  else {  
                      mapping = (short[])m_mappings.get(dtm);
                      if (mapping == null) {
                          mapping = mappableDOM.getMapping(
                                       m_translet.getNamesArray(),
                                       m_translet.getUrisArray(),
                                       m_translet.getTypesArray());
                          m_mappings.put(dtm, mapping);
                          m_currentDTM = dtm;
                          m_currentMapping = mapping;
                      }
                  }
                  
                  int expType = mappableDOM.getExpandedTypeID(node);
                  
                  // %OPT% The mapping array does not have information about all the
                  // exptypes. However it does contain enough information about all names
                  // in the translet's namesArray. If the expType does not fall into the
                  // range of the mapping array, it means that the expType is not for one
                  // of the recognized names. In this case we can just set the type to -1.
                  if (expType >= 0 && expType < mapping.length)
                    type = mapping[expType];
                  else
                    type = -1;
                  
              } 
              else {
                  return INHERIT;
              }
  
              if (m_filter.stripSpace(dom, node, type)) {
                  return STRIP;
              } else {
                  return NOTSTRIP;
              }
          } else {
              return NOTSTRIP;
          }
      }
  }
  