SiblingSelector.java

package org.cdlib.xtf.textEngine.facet;


/*
 * Copyright (c) 2004, Regents of the University of California
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 * - Neither the name of the University of California nor the names of its
 *   contributors may be used to endorse or promote products derived from this
 *   software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
import java.util.HashSet;

/** Select all siblings of each incoming group. */
public class SiblingSelector extends GroupSelector 
{
  private HashSet parents = new HashSet();

  public void reset(boolean conservative) {
    super.reset(conservative);
    parents.clear();
  }

  public void process(int group) 
  {
    // In conservative mode, we have to select the entire tree
    if (conservative) {
      next.process(group);
      return;
    }

    // Normal (non-conservative mode)... Have we seen this parent before?
    // If so, ignore it.
    //
    int parent = counts.parent(group);
    Integer parentKey = Integer.valueOf(parent);
    if (parents.contains(parentKey))
      return;

    // Okay, process all the children under this parent.
    for (int kid = counts.child(parent); kid >= 0; kid = counts.sibling(kid)) {
      if (!counts.shouldInclude(kid))
        continue;
      next.process(kid);
    }

    // And record that we've finished this parent now.
    parents.add(parentKey);
  } // process()

  public String toString() {
    return "siblings -> " + next.toString();
  }
}