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 mf.org.apache.xerces.util;
  
  import java.util.Collections;
  import java.util.Enumeration;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.Map;
  
  import mf.org.apache.xerces.xni.Augmentations;
  
  /**
   * This class provides an implementation for Augmentations interface.
   * Augmentations interface defines a hashtable of additional data that could
   * be passed along the document pipeline. The information can contain extra
   * arguments or infoset augmentations, for example PSVI. This additional
   * information is identified by a String key.
   * <p/>
   *
   * @author Elena Litani, IBM
   * @version $Id: AugmentationsImpl.java 606488 2007-12-22 20:40:16Z mrglavas $
   */
  public class AugmentationsImpl implements Augmentations {
  
      private AugmentationsItemsContainer fAugmentationsContainer =
              new SmallContainer();
  
      /**
       * Add additional information identified by a key to the Augmentations structure.
       *
       * @param key  Identifier, can't be <code>null</code>
       * @param item Additional information
       * @return the previous value of the specified key in the Augmentations strucutre,
       * or <code>null</code> if it did not have one.
       */
      @Override
      public Object putItem(String key, Object item) {
          Object oldValue = fAugmentationsContainer.putItem(key, item);
  
          if (oldValue == null && fAugmentationsContainer.isFull()) {
              fAugmentationsContainer = fAugmentationsContainer.expand();
          }
  
          return oldValue;
      }
  
      /**
       * Get information identified by a key from the Augmentations structure
       *
       * @param key Identifier, can't be <code>null</code>
       * @return the value to which the key is mapped in the Augmentations structure;
       * <code>null</code> if the key is not mapped to any value.
       */
      @Override
      public Object getItem(String key) {
          return fAugmentationsContainer.getItem(key);
      }
  
      /**
       * Remove additional info from the Augmentations structure
       *
       * @param key Identifier, can't be <code>null</code>
       */
      @Override
      public Object removeItem(String key) {
          return fAugmentationsContainer.removeItem(key);
      }
  
      /**
       * Returns an enumeration of the keys in the Augmentations structure
       */
      @Override
      public Enumeration keys() {
          return fAugmentationsContainer.keys();
      }
  
      /**
       * Remove all objects from the Augmentations structure.
       */
      @Override
      public void removeAllItems() {
          fAugmentationsContainer.clear();
      }
  
      @Override
      public String toString() {
          return fAugmentationsContainer.toString();
      }
  
      static abstract class AugmentationsItemsContainer {
          abstract public Object putItem(Object key, Object item);
  
          abstract public Object getItem(Object key);
  
          abstract public Object removeItem(Object key);
  
          abstract public Enumeration keys();
  
          abstract public void clear();
  
          abstract public boolean isFull();
  
          abstract public AugmentationsItemsContainer expand();
      }
  
      final static class SmallContainer extends AugmentationsItemsContainer {
  
          final static int SIZE_LIMIT = 10;
          final Object[] fAugmentations = new Object[SIZE_LIMIT * 2];
          int fNumEntries = 0;
  
          @Override
          public Enumeration keys() {
              return new SmallContainerKeyEnumeration();
          }
  
          @Override
          public Object getItem(Object key) {
              for (int i = 0; i < fNumEntries * 2; i = i + 2) {
                  if (fAugmentations[i].equals(key)) {
                      return fAugmentations[i + 1];
                  }
              }
  
              return null;
          }
  
          @Override
          public Object putItem(Object key, Object item) {
              for (int i = 0; i < fNumEntries * 2; i = i + 2) {
                  if (fAugmentations[i].equals(key)) {
                      Object oldValue = fAugmentations[i + 1];
                      fAugmentations[i + 1] = item;
  
                      return oldValue;
                  }
              }
  
              fAugmentations[fNumEntries * 2] = key;
              fAugmentations[fNumEntries * 2 + 1] = item;
              fNumEntries++;
  
              return null;
          }
  
  
          @Override
          public Object removeItem(Object key) {
              for (int i = 0; i < fNumEntries * 2; i = i + 2) {
                  if (fAugmentations[i].equals(key)) {
                      Object oldValue = fAugmentations[i + 1];
  
                      for (int j = i; j < fNumEntries * 2 - 2; j = j + 2) {
                          fAugmentations[j] = fAugmentations[j + 2];
                          fAugmentations[j + 1] = fAugmentations[j + 3];
                      }
  
                      fAugmentations[fNumEntries * 2 - 2] = null;
                      fAugmentations[fNumEntries * 2 - 1] = null;
                      fNumEntries--;
  
                      return oldValue;
                  }
              }
  
              return null;
          }
  
          @Override
          public void clear() {
              for (int i = 0; i < fNumEntries * 2; i = i + 2) {
                  fAugmentations[i] = null;
                  fAugmentations[i + 1] = null;
              }
  
              fNumEntries = 0;
          }
  
          @Override
          public boolean isFull() {
              return (fNumEntries == SIZE_LIMIT);
          }
  
          @Override
          public AugmentationsItemsContainer expand() {
              LargeContainer expandedContainer = new LargeContainer();
  
              for (int i = 0; i < fNumEntries * 2; i = i + 2) {
                  expandedContainer.putItem(fAugmentations[i],
                          fAugmentations[i + 1]);
              }
  
              return expandedContainer;
          }
  
          @Override
          public String toString() {
              StringBuffer buff = new StringBuffer();
              buff.append("SmallContainer - fNumEntries == ").append(fNumEntries);
  
              for (int i = 0; i < SIZE_LIMIT * 2; i = i + 2) {
                  buff.append("\nfAugmentations[");
                  buff.append(i);
                  buff.append("] == ");
                  buff.append(fAugmentations[i]);
                  buff.append("; fAugmentations[");
                  buff.append(i + 1);
                  buff.append("] == ");
                  buff.append(fAugmentations[i + 1]);
              }
  
              return buff.toString();
          }
  
          final class SmallContainerKeyEnumeration implements Enumeration {
  
              Object[] enumArray = new Object[fNumEntries];
              int next = 0;
  
              SmallContainerKeyEnumeration() {
                  for (int i = 0; i < fNumEntries; i++) {
                      enumArray[i] = fAugmentations[i * 2];
                  }
              }
  
              @Override
              public boolean hasMoreElements() {
                  return next < enumArray.length;
              }
  
              @Override
              public Object nextElement() {
                  if (next >= enumArray.length) {
                      throw new java.util.NoSuchElementException();
                  }
  
                  Object nextVal = enumArray[next];
                  enumArray[next] = null;
                  next++;
  
                  return nextVal;
              }
          }
      }
  
      final static class LargeContainer extends AugmentationsItemsContainer {
  
          private final HashMap fAugmentations = new HashMap();
  
          @Override
          public Object getItem(Object key) {
              return fAugmentations.get(key);
          }
  
          @Override
          public Object putItem(Object key, Object item) {
              return fAugmentations.put(key, item);
          }
  
          @Override
          public Object removeItem(Object key) {
              return fAugmentations.remove(key);
          }
  
          @Override
          public Enumeration keys() {
              return Collections.enumeration(fAugmentations.keySet());
          }
  
          @Override
          public void clear() {
              fAugmentations.clear();
          }
  
          @Override
          public boolean isFull() {
              return false;
          }
  
          @Override
          public AugmentationsItemsContainer expand() {
              return this;
          }
  
          @Override
          public String toString() {
              StringBuffer buff = new StringBuffer();
              buff.append("LargeContainer");
              Iterator entries = fAugmentations.entrySet().iterator();
              while (entries.hasNext()) {
                  Map.Entry entry = (Map.Entry) entries.next();
                  buff.append("\nkey == ");
                  buff.append(entry.getKey());
                  buff.append("; value == ");
                  buff.append(entry.getValue());
              }
              return buff.toString();
          }
      }
  }
  